Pyrotechnics LogROCKETS The following are dimensions and optimized fuel compositions for rockets tested up to this date (4/6/85). One ounce: Case length................3 1/4 inches Inside diameter............ 5/16 inches Overall length of spindle..2 3/4 inches Choke diameter............. 5/32 inches Fuel: Potassium nitrate, charcoal dust, sulfur (8:4:2). Three ounce: Case length................4 1/2 inches Inside diameter............ 7/16 inches Overall length of spindle.. 4 inches Choke diameter............. 1/4 inches Fuel: Potassium nitrate, charcoal dust, sulfur (8:3:2). Four ounce: Case length................5 inches Inside diameter............ 1/2 inches Overall length of spindle..4 1/4 inches Choke diameter............. 1/4 inches Fuel: Potassium nitrate, charcoal dust, sulfur (8:6:2). Cases for one ounce rockets were made by wrapping an eleven inch length of Xerox paper (heavy typing paper) around a 5/16 inch dowel rod. These were pasted with a continuous coating of Elmer's glue. These cases are light weight and rock hard when dry. For my first tests of one ounce rockets I used a 3:2:1 by volume mixture of potassium nitrate, charcoal, sulfur. These exploded like fire crackers when ignited. I then tried 8:4:2 by weight. This worked very well and gave a surprising performance for such a small rocket. Fuel mixtures for all rockets tested thus far were lightly moistened with water. I have found this to be vital in spite of the fact that all the books say to load them dry. I tested a four ounce rocket loaded dry with an 8:6:2 mixture and it exploded violently blowing its heavy casing to bits. This same combination turned out to be the optimum formula when loaded damp and thoroughly dried before firing. A one ounce rocket loaded dry with 8:4:2 also exploded. I have noticed that when the fuel is right rockets of all sizes make a similar sound. It is the sound of a gas being released under high pressure. It falls between a hiss and an explosive report. I made the casings for the three ounce rockets from pieces cut from file folders. A piece of this heavy paper 4 1/2 x 8 1/2 to 9 inches is wrapped around a 7/16 inch dowel rod. It is pasted with a continuous layer of Elmer's glue. For three ounce rockets an 8:4:2 mixture produced rockets which flew consistently but poorly. These rose about 20 feet then leveled off and fell in a slow curve. When loaded with 8:3:2 they were outstanding. These flew completely out of sight against an overcast sky. I tested these at 4:00 pm this afternoon. Some of the casings for the four ounce rockets were made from file folder paper and some from poster board, which is very slightly thicker. When using file folders, the pieces used were 5 x 11 3/4 inches. When using poster board, I used 5 x 11 inches. In both cases a 1/2 inch dowel rod was used as a form and they were pasted with a continuous layer of Elmer's glue. I set up an experiment with four ounce rockets loaded with 8:6:2, 8:5:2, and 8:4:2 fuel mixtures. The 8:6:2 mixture was spectacular. Like the three ounce rockets, it flew completely out of sight. The 8:5:2 mixture exploded blowing out the end plug. The casing and nozzle were left intact. I chose not to fire the rocket with the 8:4:2 mixture to avoid creating a loud, case bursting explosion in a residential area. I was doing this test in -----'s back yard. Threatening weather discouraged me from going to my usual test site on a remote river bank. (On 4/10/85 I tested the four ounce rocket with the 8:4:2 fuel mixture fully expecting an explosion. My expectation was not disappointed. The rocket shot a few feet into the air and exploded with a load report). All rockets tested so far were stabilized with a guide stick three times the length of the casing. The nozzles and end plugs were formed from nozzle-ite. They were fired from a soft drink bottle and were tilted to a small angle from vertical. When they flew (as apposed to fizzling or exploding) they always went in the direction they were pointed with one exception. The exception was a one ounce rocket which flipped over for some reason just as it cleared the top of the bottle and flew in a straight horizontal line into a wooden fence. WHISTLES These experiments were conducted on March 30, 1985. The composition used was 70% by weight Potassium perchlorate, 30% by weight Sodium Salicylate. The chemicals were dried separately in a 150 to 175 degree oven then cooled and mixed in a one quart ziploc freezer bag. The lumps in the perchlorate were pressed out by rolling a one inch dowel rod over the composition while it was enclosed in the freezer bag. I stored the mixture in a sealed glass jar until I was ready to load it into casings. The books say this composition is hygroscopic so I wanted to start with dry ingredients and keep them dry for the experiment. I made the casings from file folder paper rolled extra thick. This composition produces a lot of hot flame while burning. I learned from earlier experiments that unless a thick casing is used the top part of the casing will be burned away before all the composition is consumed. Since the depth of the casing above the composition effects the pitch of the whistle, I wanted to avoid this. I firmly pressed (no pounding) the mixture into the casings using dowel rods appropriate to the sizes of the casings. I found the mixture to be sensitive to heat and easy to ignite with a piece of safety fuse resting lightly on top of it in the casing. All casings were plugged at one end with nozzle-ite. After drying I hot glued them to thin 2 x 2 inch pieces of wood to form a base. I then pressed in the composition and took them to the test site. These are the casing sizes and results of the tests: Inside diameter 3/8 inches Length of case 3 1/2 inches Not a very loud whistle. Quality of the whistle diluted with a lot of hissing. Inside diameter 1/2 inches Length of case 3 1/8 inches Better, but still not very loud and too much hissing with the main note of the whistle. Inside diameter 1/2 inches Length of case 4 1/2 inches Penetrating whistle. Acceptable. Inside diameter 5/8 inches Length of case 3 1/2 inches Loud. A good whistle. Inside diameter 3/4 inches Length of case 4 1/8 inches Best yet. Loud clear note. Impressive. I tape recorded these tests. At the end of the tape I made this comment: "My conclusion made right here on the test site at this moment without reviewing the tape is that when it comes to whistles bigger is better". On April 4, 1985 I decided to find out if there was an explosion hazard with this composition and also whether or not it could be used as a whistling rocket fuel. I placed 3/4 of a teaspoonful of the mixture in a commercially made casing 5/8" x 1 3/4" with paper end plugs. I also loaded a four ounce rocket case with the composition and took these to my test site. When the composition was ignited in the salute casing it detonated with a loud report rivaled only by a good grade of flash powder. The casing was blown to bits. It is worth noting that the best grade of black powder I can make merely blew out the end plugs in a similar experiment. When the rocket was ignited, it too detonated with a horrendous report. The casing was blown to pieces and the portion of the guide stick which was attached to the rocket was blown away leaving the remainder in the bottle. TIME DELAY INCENDIARY (March 25, 1985) I have been experimenting with an extremely interesting time delay incendiary I learned about from "The Improvised Munitions Black Book Vol. 3". It consists of HTH swimming pool purifier (Calcium hypochlorite 65%, inert ingredients 35%) and brake fluid (Diethylene glycol). I will describe the experiments. The ambient air temperature was 39 degrees fahrenheit. I placed about 1 rounded teaspoonful of HTH on the bottom of an inverted tin can. Using a medicine dropper, I added enough brake fluid to saturate the HTH (two droppersful). The mixture remained completely unchanged in appearance for 6 minutes and 15 seconds at which time it suddenly ignited and burned vigorously with a reddish flame. I cleaned off the can and repeated the experiment. This time ignition occurred in 5 minutes. I placed a single drop of brake fluid on a much smaller pile of HTH to see if this quantity of material would ignite. When nothing happened after 11 minutes, I dumped the mixture into a puddle of water and concluded the experiment. The delay before ignition of this material seems to be related to the amount of material used. Greater quantity gives a shorter delay. When this mixture burns it generates a very foul smelling and irritating smoke. I did these experiments at night and it made a spectacular demonstration. THERMITE This experiment was reported to me in a letter received 4/6/85 from my friend -----. "I used 3 parts red iron oxide to 1 part aluminum powder (FULL AUTO'S). I placed a pile on top of a campers tin; inserted about one inch of magnesium ribbon; lit the ribbon with a lighter; and was astonished. It burns quite rapidly with a brilliant orange flame, leaving behind molten pools of (I assume) iron. All of my previous experiments with homemade iron oxide were not nearly so successful. Incidentally, the iron oxide was from Hagenow. It melted through the tin can and onto a rock below the can, causing the sandstone to heat up and explode, throwing little bits of thermite everywhere. It was quite dramatic!" FUSE (2/6/85) I made excellent black match fuse from this formula. Parts are by volume. Potassium nitrate 4 Charcoal dust 2 Sulfur 1 Corn starch 1 Mix with cold tap water to the consistency of molasses. Use 8 strands of thread. Dip into mixture and pull through a 1/16" die made by drilling a hole in a plastic spoon. Dry in an oven at 200 degrees F. Oven drying is important or the fuse will not stiffen properly. A larger fuse, great for igniting rockets, can be made using a heavy piece of cotton string instead of multiple strands of thread. For this use a 9/64" die. Also this (by volume): Flash powder 2 Potassium perchlorate 1/4 Corn starch 1/4 Treat the same as black match. Burns like a small sparkler more slowly than black match. (3/22/85) Slow fuse test. Heavy cotton string soaked in solution of (by volume): Potassium nitrate 1 Corn starch 1 Water 6 Smolders about 1 1/2 minutes per inch. Forms small molten globules which run along the unburned part of the fuse ahead of the fire. In this test these did not cause a premature ignition of this part of the fuse. Second slow fuse experiment. Same type of string soaked in: Potassium nitrate 1 Cold tap water 3 This formed a saturated solution. The string was lightly wrung out by passing through thumb and forefinger. Same burn rate as the fuse made with corn starch but showed no tendency to form molten globules which might run down the fuse and cause premature ignition. I made another interesting slow fuse by soaking a strip of newspaper 1 1/2 inches wide in this mixture. After drying I folded it into a "V" shaped trough so it could stand on its own with most of its area protected from contact with any surfaces. When touched at one end with a lighted match it made a nice smoldering fuse which burned quite a bit faster than the string type. All these fuses tend to go out if they are touching anything. I made a very promising time delay fuse by taking 3 inch lengths of heavy (about 1/8 inch) cotton string and treating them as above then dipping one end of each into black match paste. I taped the ends with the black match composition to the bottom of a tin can in such a way that the parts without the black match were hanging free. These dependably ignited their black match treated ends in about 3 minutes. These could be taped to the fuse of any pyrotechnic device of choice when a long time delay is wanted. CHEMICAL IGNITION EXPERIMENTS These experiments were performed around the end of March 1985. AMMONIUM NITRATE/ZINC DUST - I dried some ammonium nitrate prills in a 175 degree oven then powdered them with a mortar and pestle. I mixed 3 parts by volume ammonium nitrate with 1 part by volume zinc dust. I poured a teaspoonful of the mixture on the bottom of a tin can and made a depression in it with a spoon. A single drop of water placed in the depression caused a strong reaction in about 7 seconds which generated a lot of heat and smoke but no flame. To test the ability of this mixture to ignite other material, I repeated the experiment this time placing a piece of black match into one edge of the mixture. When the reaction reached the black match, it was ignited. POTASSIUM PERMANGANATE/GLYCERIN - I put a spoonful of potassium permanganate on the bottom of a tin can and made a depression in it with a spoon. I dropped three drops of glycerin into the depression. In a few seconds, the time it took the glycerin to start soaking in, the mixture burst into flames. Only the area where permanganate and glycerin were mixed were involved in the combustion. The ambient temperature was 61 degrees F. Later in the evening when the temperature was down to 49 degrees I repeated the experiment. It took much longer for ignition to occur (about one minute). The mixture smoked for several seconds before bursting into flame. TWO OUNCE ROCKETS (Log entry 4/10/85) These are the dimensions for two ounce rockets. Case length................3 1/2 inches Inside diameter............ 3/8 inches Overall length of spindle..3 inches Choke diameter............. 3/16 inches Fuel: Potassium nitrate, charcoal dust, sulfur (optimum component ratios not yet determined). I loaded two casings with each of these fuel mixtures: 8:6:2, 8:5:2 and 8:4:2. I tested these today with the following results: 8:6:2 - First rocket flew smoothly in a high arch and fell in the middle of the river. Second rocket rose about six feet; leveled off and fell quickly. The remaining four rockets all rose from the launcher and fell immediately. The behavior of these rockets was far from what I expected in light of earlier experiments with rockets of different sizes. There appears to be an interactive relationship between choke diameter and the internal diameter and length of the case which does not track as one would expect from one size rocket to another. It appears that two ounce rockets are going to require an 8:3:2 or hotter mixture to fly properly. I will test this tomorrow if weather permits. Good cases for two ounce rockets can be made from 3 1/2" x 5 7/8" pieces of file folder paper. One letter size file folder can be used to make eight cases. I also tested a one pound rocket today with these dimensions: Case length................7 1/2 inches Inside diameter............ 3/4 inches Overall length of spindle..6 3/4 inches Choke diameter...............1/4 inches Fuel: Sodium nitrate, granulated sugar (8:5). In spite of the small choke diameter, this rocket did not generate enough thrust to fly. I have experimented with nitrate/sugar mixtures with these ratios: 8:6, 8:5, and 7:3. When burned in the open 8:6 leaves a carbon residue (an excess of sugar). 8:5 leaves a whitish residue (an excess of nitrate). 7:3 leaves a whitish residue and was the slowest burning. The 8:5 mixture had the fastest burn rate. SALUTES I have settled on several standardized sizes for salutes. The sizes are based on the volume of powder required to fill them approximately 3/4 full. Length of case Internal diameter Powder volume Inches Inches Teaspoons -------------- ----------------- ------------- 2 1/2 1/4 1/4 2 5/8 1/2 4 3/8 1 3 1/2 5/8 2 3 15/16 4 I also make giant cherry bombs with an internal diameter of 1 1/4 inches using a ping pong ball for a mold. The powder load is 3 teaspoonfuls. The best flash powder I have tested for use in salutes consists of 7 parts by weight potassium perchlorate, 3 parts by weight German black aluminum. This is truly outstanding. As a test of its explosive power, I put 1/2 teaspoonful of this composition in a commercial casing 5/8" ID x 1 3/4" with paper end plugs. I side fused it with a 6 inch length of safety fuse. I made a second one the same way as insurance against a dud. ----- and I took one of these and a 3 x 4 1/4" tin can to an abandoned house. I put the salute in the can and set it in a closet. ----- lit the fuse and pushed the door shut. The door had no latch. We quickly went to another room for safety. When the device detonated, it felt like a large safe had been tipped over and fallen on the floor. The can was blown to pieces. The closet door was blown open, and chunks of plaster fell from the ceiling in the closet. Ignoring my advice to the contrary, ----- took the other salute which I had brought along as insurance; lit it and threw it into the crawl space under his house. His wife, who was in the house at the time, nearly went into cardiac arrest. Because of the tremendous explosive power of this composition, I haven't been experimenting lately with salutes containing more than 1/2 teaspoonful of powder. However, come the 4th of July, I have plans to move the state of West Virginia two inches to the left on the North American continent. About two weeks earlier on Feb. 16, 1985 we did another experiment using chemicals from Full Auto. The composition was 2 parts potassium perchlorate, 1 part powdered aluminum, 1 part sulfur. I made up several salutes containing 4 teaspoonfuls each of this powder. ----- and I tramped through the snow down to the river bank where we taped these to rocks. We lit them one at a time and threw them into water about 1 1/2 feet deep. Each time one of these exploded, it sent up a column of water three stories high. The report was almost entirely suppressed by the water, but the thud of the explosion could be felt. (Log entry 4/11/85) - ROCKETS: I just got back from a very successful test of two ounce rockets. I loaded two cases with potassium nitrate, charcoal dust, sulfur (8:3:2). 13 grams of this composition were moistened with 4 drops of water from a faucet. Note: 1 of these drops equals 5 drops from a medicine dropper. This amount of fuel was just right to fill two rockets. The finished rockets were dried in a warm oven (150 - 175 degrees F.) for about 14 hours. The first rocket was attached to a guide stick 10 1/2 inches long half way up the case using masking tape. I inserted a piece of black match all the way into the cavity with eight inches on the outside to serve as a fuse. I used a soft drink bottle as a launcher. This rocket shot quickly out of sight. I attached the second rocket to a 12 inch stick and fused it the same way. I got farther back from this one in hopes of keeping it in sight but it quickly rose into oblivion. These little 3 1/2 inch wonders can really fly! WHISTLES: I also tested two whistles today. Both cases were 3/4" x 3 1/4". One end was plugged with a quarter inch of nozzle-ite. Both were hot glued to a 2" x 2" piece of wood for a base. I loaded the first case with 7 teaspoonfuls of composition (7:3 potassium perchlorate/sodium salicylate). This filled it to 1/2 inch from the top. A piece of safety fuse failed to ignite the composition. I made an effective fuse by taping two short pieces of black match to the end of a piece of safety fuse. The composition burned vigorously for 4 seconds before whistling began. It then whistled for 6 1/2 seconds with the pitch descending from high to low. The whistle was so loud it was uncomfortable to my ears standing 6 - 8 feet away. It also attracted the attention of a 14 year old boy in the neighborhood who came to see what was happening. I loaded the second whistle with 6 teaspoonfuls of composition which filled it to 3/4 of an inch from the top. This one burned for 2 1/2 seconds before whistling began, then whistled for 6 1/2 seconds exactly like the first one. The composition hisses loudly before whistling begins. These tests demonstrate that in this size casing the composition burns at a rate of 4 - 4.2 seconds per inch and that the length of empty tubing above the composition required for whistling to begin is 1.375 - 1.5 inches. SALUTES: These are my verbatim comments from a tape recording made at the time: "Now just for fun we're going to take a couple of these commercial salutes called Big Apple Bombs that are real fiascoes. They didn't even blow up the casing. They look similar to a cherry bomb. We've reloaded them with some of our own stuff here on the spot. We improvised a technique for doing it using a little tissue paper and candle wax to seal in the fuse. So now we're going to light them and throw them and see what happens. The first one's lit right now. (loud report) In case it's not obvious on the tape, that salute which had probably less than 1/8 teaspoonful of powder had a tremendous report. This second one has been buried inside a sack of some kind of fertilizer or commercial soil for planting potted plants. It's buried completely under it. I'm going to get back a little farther from this one this time. Let 'er rip. (loud report) Still a significant report". NOZZLE AND PLUG COMPOSITION (Log entry 4/12/85) I wanted to see if I could come up with a composition for forming rocket nozzles and end plugs similar to Nor Starr's Nozzle-ite. I mixed three batches of composition consisting of plaster of paris and common earth. The earth used was plain "dirt" dug from a creek bank. It was selected for its freedom from sand and vegetable matter. The three mixtures were plaster of paris/earth in ratios of 1:1, 1:2, and 1:3 by volume. A composition for rocket nozzles should be hard and strong after drying. It should be easy to crumble while moist for ease of loading but should form a homogeneous mass when rammed in a case. It should grip the wall of the casing so it will not dislodge under pressure. It should not crack when subjected to the heat of rocket exhaust. Moisture content was the main factor controlling the ability of the composition to crumble but it also crumbles more easily as the quantity of earth increases. Samples of each mixture were moistened and pressed into a flat piece between thumb and forefinger. A quantity of each mixture was also rolled into a small ball. These were allowed to set for at least 30 minutes and were then dried for 4 hours in a warm oven. To test the strength of the samples, I broke each of the flat pieces with my thumbs and fingers. The 1.1 mixture was much stronger than the others. A flat piece and a ball from each sample was heated to a red glow with a propane torch. None of the samples cracked from this treatment. I moistened another sample of the 1.1 mixture and pressed it into a flat piece. I heated this while still damp with the torch. Little steam explosions blew bits of the material away from the main mass. It was similar to popping corn without a lid. The remaining material was so weak it fell apart with almost no pressure. The other samples were not weakened by being heated. This suggests that the material should be allowed to set before drying in the oven to achieve its full strength. Conclusion: Nozzle-ite is probably a mixture of plaster of paris and fire clay in a ratio of about 1:1. The 1:1 mixture of plaster of paris and earth should be an adequate substitute. ANOTHER NOZZLE EXPERIMENT (Log entry 4/13/85) Today I tested straight plaster of paris as a possible compound for forming rocket nozzles and plugs. It behaves very much like Nozzle-ite except it takes more water to moisten it properly. I performed the same tests as with the other mixtures -- flat piece for break test; ball for heat test. It was at least as good, if not better, than the earlier mixtures tested. When I make my next batch of rockets, I will use this in a couple of them as a final test. ROCKET BURN RATE OBSERVATION (Log entry 4/13/85) After tuning several 1, 2, 3, and 4 ounce rockets, I have noticed that the burning rate of the fuel follows a characteristic curve. This is true whether the composition is too fast, too slow, or just right. From the moment of ignition, The pressure rises rapidly to a short duration maximum them falls off in a relatively slow curve. The rocket has already left the launcher and started its flight BEFORE this burst of maximum pressure is attained. I base this conclusion on the following observations: When the composition is too fast, resulting in an explosion, about half the time the rocket shoots 4 - 7 feet into the air before bursting. When the composition is too slow, but still fast enough to produce a lift off, the rocket draws this curve by it flight. When the fuel component ratios are right this burst of pressure will send even a 2 ounce rocket out of sight in daylight. "Pressure curve" is probably a better term than "burn rate" for describing this since pressure is a function of the quantity of fuel involved as well as rate of burning. The timing of the occurrence of maximum pressure and its duration are probably the most critical factors in tuning any pyrotechnic rocket. Unless one wishes to depart from the standardized conventional parameters of rocket body and nozzle dimensions, the way to achieve this timing is through adjustment of fuel composition and method of compaction. Considering the performance of rockets I am currently producing, I see no need to tamper with dimensions. My main concern at this time is to achieve uniform performance among rockets of the same caliber. Each size rocket probably has an optimum pressure curve for overcoming the inertia and accelerating the mass of the rocket body added to the steadily decreasing mass of the fuel. DROP SIZE OBSERVATION (Log entry 4/13/85) I have noticed that the sizes of drops of water are not uniform when produced by different means. For example, a drop of water from my kitchen faucet has five times the volume of a drop of water from a medicine dropper. Since I am concentrating at this time on standardizing fuel and nozzle compositions, I feel it is important to note this. IMPORTANT: MOISTURE CONTENT OF ROCKET FUEL I have been puzzling over the results of the experiment with 2 ounce rockets conducted on 4/10/85. Two casings each were loaded with 8:6:2, 8:5:2, and 8:4:2. Both rockets loaded with 8:6:2, which should have been the slowest mixture, produced more thrust and higher flights than any of the others. The one variable I was not paying close attention to was how much water I was adding to the mixtures. In an earlier experiment, a 4 ounce rocket loaded dry with 8:6:2 exploded violently. When a mixture with these same ratios was moistened before loading, the rocket flew perfectly. It is clear that premoistening the fuel slows its burning rate. The evidence indicates that the AMOUNT of water added is far more critical than I realized. The moderating effect of the water may come from the fact that it aids in compaction or it may be caused by the effect of some of the potassium nitrate going into solution and recrystalizing as the fuel dries. Probably, both factors are involved. Fortunately, in my last experiment with 2 ounce rockets I paid close attention to the amount of water used and documented it in this log. Four drops (from a faucet) were added to 13 grams of 8:3:2 fuel. The two rockets loaded with this fuel flew beautifully and uniformly. The advantage of being able to predictably duplicate this performance is obvious. In order to establish a good standard for measuring the water to be added, I devised an experiment to determine the exact volumetric relationship between the drops used in the successful fuel and those produced by a medicine dropper. I held the body of a 10 cc hypodermic syringe under the faucet and counted the number of drops required to fill it to the 8 cc mark. It took 25 drops. I then counted the number of drops from a medicine dropper which filled it to the same volume -- 160 drops. Therefore, 1 drop from the faucet equals 6.4 from the medicine dropper. To make it easier to measure out the fuel, I carefully weighed and mixed 39 grams of the components then counted the number of teaspoonfuls in that amount. It was 12. Four teaspoonfuls would equal the 13 grams used in the original experiment. The nearest whole number of drops from the medicine dropper would be 26. PROPOSED 3 IN 1 EXPERIMENT: To 4 teaspoonfuls of fuel add 26 drops of water. Use this to load two 2 ounce rockets. Prepare another batch of fuel the same way and load two more rockets. Use plaster of paris for the nozzles on these two. These are the questions I hope to answer with this experiment: 1. Will these rockets perform as well as those in the successful test? 2. Assuming they fly successfully, by firing them at night, will it be possible to follow their flight by their luminous exhaust? 3. Will the plaster of paris nozzles work as well as nozzle-ite? (Log entry 4/14/85) Today I did the 3 in 1 experiment exactly as described above. These are the answers to the posed questions. 1. The two rockets made using nozzle-ite performed exactly like the two in the successful experiment. The first of the rockets using plaster of paris also performed exactly the same. The second of these shot well up into the sky, but there was a sudden burst of sparks suggesting that it may have blown out its nozzle or end plug. 2. By firing the rockets at night it was possible to see part of their flight by the exhaust. This cut out well before the top of the flight and so the rockets were still lost from sight. 3. The first rocket using plaster of paris performed just like the ones with nozzle-ite. Because of the uncertain performance of the second rocket, the use of plaster of paris as a nozzle compound is left in question. WHITE FLARE EXPERIMENT (Log entry 4/14/85) I made four small white flares using this formula: Potassium perchlorate 25 parts Powdered aluminum 23 parts Dextrin 2 parts The perchlorate and aluminum were from Full Auto. The amount of water added was 30 drops for each 4 teaspoonfuls. I loaded two casings each of these sizes: 9/32" x 2" and 3/8" x 3". All casings had a 1/4 inch plug of plaster of paris and were primed with 3/8 inch of black powder paste which also served to hold a piece of safety fuse. All these flares were brilliant and shot a dense shower of tiny sparks several feet past their burning ends. If part of the powdered aluminum were replaced with a coarser grade, these could be really spectacular. This was a fierce burning composition and needs to be slowed down. The burning rate of the 9/32 inch flares was .55 seconds per inch. The 3/8 inch flares burned at a rate of .66 seconds per inch. HOW TO MEASURE CHEMITE (Log entry 4/14/85) One tenth of one percent by weight of chemite is added to flash powder. To simplify measuring the required amount, I have converted weight to volume. One teaspoonful of chemite weighs .6 grams. The amount needed for two ounces of flash powder is .0568 grams or .03408 teaspoonfuls. This is the amount of chemite held by a cylinder 1/4 inch in inside diameter by 1/4 inch long. To make a measuring spoon, cut a strip of paper 1/4 inch wide and roll it into a thin cylinder around a 1/4 inch dowel rod. Use Elmer's glue to hold it and give it stiffness. Hot glue this little cylinder to a thin piece of cardboard like a piece of index card. Hot glue on a handle and it's done. I used a piece of wood from a swab of the type used to clean tape heads. To make a spoon for use with one ounce of powder, repeat the process with a strip of paper 1/8 inch wide or simply fill the other one half full. (Log entry 4/18/85) ANOTHER ALUMINUM FLARE EXPERIMENT - In an effort to slow down the burn rate of my aluminum flares, I added 1 teaspoonful of corn starch to 3 tablespoonfuls of the composition (potassium perchlorate 25 parts, aluminum 23 parts, dextrin 2 parts). I added much more water than before until the mixture could be molded like modeling clay. I loaded 5 casings with this and placed them in the oven to dry. I carefully controlled the temperature with the aid of a thermometer and did not let it go above 175 degrees F. In spite of this precaution, pressure built up inside the casings causing several to burst explosively, which threw composition all over the inside of the oven. One or two blew about half the composition out the open end. (Log entry 4/18/85) AMMONIUM NITRATE/ALUMINUM EXPERIMENT - To see if ammonium nitrate and aluminum powder would form a combustible mixture, I made up two samples to test. One was 3 parts by volume ammonium nitrate, 1 part by volume aluminum. The second was 1 part by volume ammonium nitrate, 1 part by volume aluminum. To prepare the ammonium nitrate, I dried 1 1/2 cups of the fertilizer grade prills in a 175 degree oven for 45 minutes. I then powdered it in a blender and filtered it through a fine mesh tea strainer. The powdered aluminum was from Full Auto. For the test, I placed a piece of heavy black match on a tin can and covered the end with 1/2 teaspoonful of composition. The first mixture did not ignite. The second mixture ignited and burned with an extremely bright white flame. It burned quietly and somewhat unevenly for approximately 15 seconds -- an interesting performance for 1/2 teaspoonful of loose composition. By comparison, the perchlorate/aluminum/dextrin mixture burned in an instantaneous flash when ignited under the same conditions. In 1980 I did an experiment in which I used ammonium nitrate as a replacement for potassium nitrate in black powder. The resulting composition would not ignite. Even replacing a small portion of the potassium nitrate with ammonium nitrate caused a serious degradation in the performance of the powder. A mixture of ammonium nitrate and sugar also failed to ignite. (Log entry 4/18/85) NOTE ON HYGROSCOPICIY - I don't know which is more hygroscopic, ammonium nitrate or sodium nitrate. Both are amazing for their ability to take up moisture from the air and become damp. ----- and I were playing with a mixture of sodium nitrate and sugar one evening when the humidity was near 100%. In a matter of minutes, this mixture became so damp we could barely get it ignited. Once ignited, it frequently went out. When perfectly dry, this mixture lights easily and burns vigorously. A few months ago, I tested some sodium nitrate black powder I had made five years previously and stored in an air tight container. It was as dry and combustible as the day it was made. I also found an experimental rocket engine left over from that period in which I had used sodium nitrate and sugar for fuel. This had not been stored in a container. The fuel mixture was damp and sticky. These cheap, fertilizer grade nitrates can be used in pyrotechnic mixtures, but special care must be taken to protect such mixtures from moisture until used. (Log entry 4/19/85) AMMONIUM NITRATE/POWDERED METAL EXPERIMENTS - After reviewing my log entries on ammonium nitrate, I wondered what would happen if the zinc content in the ammonium nitrate/zinc dust incendiary were increased. Instead of 3:1 by volume, I mixed a 3:2 by volume composition. When 1/4 teaspoonful of this was ignited by fuse, it burned with spurts of bluish flame. When a drop of water was placed on the same amount, it reacted without producing any flame after about a ten second delay. In a second experiment, I mixed ammonium nitrate/zinc dust/aluminum in a ratio of 3:1:1. When 1/4 teaspoonful of this was ignited by fuse, it burned vigorously for 2 seconds with a green flame. When a drop of water was placed on the mixture, there was no reaction after several minutes. I added two more drops and worked them into the mixture. After 3 1/2 more minutes with no reaction, I terminated the experiment. NITRATE/ALUMINUM FLARE COMPOSITIONS (Log entry 4/20/85) I mixed 1 part by weight fertilizer grade sodium nitrate with 1 part by weight powdered aluminum (from Full Auto). When 1/4 teaspoonful was ignited by black match, it went up in a brilliant, gold colored flash. The burn rate was noticeably slower than the potassium perchlorate mixture. The after effect on my eyes was similar to having watched a flash cube fire. I repeated the experiment with a 1:1 mix of finely powdered barium nitrate and the same type of aluminum. This went up in an instantaneous flash with a slight green tint. I believe this mixture would be highly explosive if confined. COMPOSITION OF CHEMITE (Log entry 4/20/85) I am almost certain that chemite is silicon dioxide. A discussion of this chemical begins on page 47 of "Fireworks" by Lancaster. The last paragraph says, "The material is of extremely low density and flies about the workshop, but there is no evidence that it causes silicosis. Some firework manufacturers are said to use the material for coating iron and for adding to flash powders in the proportion of about 0.1%". This describes the physical properties of chemite. The amount to be added to flash powder also matches. PAPIER-MACHE CHERRY BOMBS (Log entry 4/21/85) I have made two sizes of cherry bombs out of papier-mache which were attractive and performed well. TO MAKE PAPIER-MACHE - Fill a blender about 3/4 full of water. Add torn pieces of scrap paper -- old computer print outs, stubs from last years bills, etc. Blend at high speed to chop the paper into small bits. Let this soak a few minutes to soften, then blend again until the result is a homogenous pulp. Place a paper towel over a colander or large strainer. Pour the pulp onto the paper towel and let it drain. Dump the wet mass and paper towel into a bowl. Lift off the paper towel. To one cup of pulp add 1 tablespoonful of corn starch and mix well. This is the raw material from which the casings will be made. The smaller cherry bombs have an outside diameter of 1 inch. To make these, scoop up 2 tablespoonfuls of pulp. Squeeze out the excess water and roll into a ball in the hands. Make as many as desired. It is strictly assembly line work at this point. I placed these in a 250 degree oven for 30 minutes to get the starch to firm up properly. This step could probably be eliminated if dextrin were used instead of corn starch. I then reduced the heat to 150 -175 degrees and let them dry for over 12 hours. The best way I found to form the cavity for the powder was to drill them straight through with a power drill. It is necessary to start with a small bit and work up to the largest size to be used. The largest size I used was 11/32" simply because it was about the right size and was handy. The more common 3/8" size should work the same. When I tried starting with a large drill bit, it chewed up the casings too much. When all the casings have been drilled, trim off the rough edges with a pair of wire cutters. Because the drill bit will chew out a hole slightly larger than its diameter, a 3/8" dowel rod will fit through the hole. Coat the inside of the hole with Elmer's glue by pushing the dowel rod all the way through, then coat the end with glue and pull it out with a twisting motion. I coated the dowel rod with paraffin first to keep the glue from sticking and to make it easier to clean. The next step is to patch the hole at one end. Make a patching compound by taking some of the pulp, which is still wet after all this time, and squeeze out as much water as possible. Press it flat and give it a good coating of Elmer's glue. Knead this well to mix in the glue. Insert the dowel rod to within 3/16" from the end. Take more than enough patching compound to fill the 3/16" hole and press it in firmly allowing the excess to spread out over the surrounding surface. If there is more compound than desired around the hole, press away the excess with a finger. Push the patched end into the palm of one hand and press firmly with a rotating motion. The patch will blend in and dry with no visible seam. The larger casings are 1 1/4 inches or a little more in diameter. They are made the same way as the smaller ones except that more pulp is used. I measured the pulp by simply grabbing a handful. It gets easy to judge after rolling a couple of them. The hole is the same diameter as before. The powder charge for the smaller cherry bombs is 10 grains. The larger ones will hold 15 grains. Make a ten grain measuring spoon out of a paper cylinder 3/8" ID x 7/16" long. An experiment has shown that trying to force in more powder will reduce the report. The powder I used was 70% potassium perchlorate/30% German black aluminum with .1% by weight chemite. Pour in the required amount of powder; insert a fuse; and pack paper toweling in around it at the top. Press the toweling down slightly below the surface of the casing. Squeeze a shallow layer of hot glue onto the toweling around the fuse. As a final touch, push the fuse into a paper cylinder to protect it and give the casing a layer of red spray paint. The end product has a very pleasing appearance. I tested some of these at 12:00 noon yesterday in -----'s back yard. The small ones gave a surprisingly loud report for such a small charge of powder. The first one seriously startled some girls who were sunbathing next door on the other side of a privacy fence. Though I am not vandalistic by nature, I found their profane exclamations quite amusing. The report from one of the larger ones containing 15 grains of powder was stunning. At this point, the consternation and outcry from next door reached such a volume that I terminated the experiment to avoid a confrontation with the police. ----- was so delighted with both the appearance and performance of these devices that I felt compelled to give him a half dozen of each size for his 4th of July stock pile. SODIUM NITRATE/ALUMINUM FLARE EXPERIMENT (Log entry 4/21/85) I made up a 1:1 by weight mixture of fertilizer grade sodium nitrate and powdered aluminum. To 6 teaspoonfuls of this composition I added 1/4 teaspoonful of dextrin. I moistened this quantity with 30 drops of water. At this point, the composition was still loose and dusty but was slightly tacky when pressed down with a spoon. I loaded four casings with this. The dimensions were 9/32" ID x 3" long. I made these by wrapping 3" x 5 1/2" strips of xerox paper around a 9/32" brass tube. Each casing had a 1/4" plaster of paris end plug and was primed with 1/2" of black powder paste after loading. I punched a hole in each casing about 1/8" from the top with an awl. I inserted a piece of 3/32" safety fuse into the hole with a little Elmer's glue to hold it. I preheated the oven to 175 degrees; switched it off; and placed the flares inside to dry. After 25 minutes, the temperature was down to 150 degrees and there had been no mishap. I switched the oven back on and let them dry for another 2 1/2 hours. When tested, the safety fuse failed to light the black powder primer in all four flares. I got them going by taping a piece of black match fuse to the top of each one. The composition in one of the flares was not ignited by the primer. Those which ignited burned for about 15 seconds with a brilliant golden fire and threw aluminum flitter 2 to 3 feet into the air. They were beautiful. In a larger size these would make a spectacular ground display. AMMONIUM NITRATE/ALUMINUM FLARE TEST - I pressed a dry composition of 1:1 by volume ammonium nitrate/aluminum into one of the 3 inch casings. I used 1/4 inch of dry black powder as a primer. This failed to ignite the composition. I got it lit by loosening some of the composition at the top and inserting a piece of black match. The flare burned for about 1 minute. It threw up very little flitter, but was impressive because of its extreme brightness. The casings for these should be very thin so they will burn away with the composition. To determine the best ratio of ammonium nitrate/aluminum, I tested several mixtures of dry loose powder. The one which burned most vigorously was 2 parts by volume ammonium nitrate to 3 parts by volume aluminum. IMPROVED PAPIER-MACHE (Log entry 4/29/85) To make an improved papier-mache for use in cherry bombs, prepare the paper in a blender as before. When squeezing out the water, don't over do it. A moderate moisture content is needed. Press the squeezed pulp into the measuring container. To one part by volume paper pulp, add one part by volume general purpose wheat flour. Mix and knead well. This will form a plastic mass which is easily molded. When dry, it is dense and fiberous and much easier to drill than the earlier composition. It is still necessary to start with a small drill bit and work up, but it is much less critical in this respect. A slightly larger bit should be used for the final drilling because the bits won't enlarge the hole as much as before. The finished casings will be more dense and a little heavier than before. SMOKE BOMBS (Log entry 4/29/85) This is from a letter from ----- dated 4/21/85. I like smoke bombs...so, I tried to slow down the burning rate of potassium nitrate/sugar mix by adding water. I used a 50/50 mix of nitrate/sugar by volume and added enough water to dampen it slightly. I then poured it into an aluminum pop can to 1/4 of an inch from the top. I filled the rest up with a dry mix of nitrate/sugar. I lit it with a length of safety fuse and I was simply amazed. The can generated smoke for about 2-3 minutes with no visible flame. The smoke generated was dense and gray in color. Incidentally, the KNO3 I used was Hi-Yield stump remover, this could make a difference, I don't know. I have not tried the experiment with pure KNO3. I repeated the experiment several times with different amounts of water. Too much water simply won't ignite. Too little causes the mix to burn much too quickly with a flame. Anyway, I was impressed with the amount of time it burned and the amount of smoke it produced. Another good smoke mix is 4 parts by volume potassium nitrate: 5 parts by volume sulfur: 1 part by volume charcoal dust. The only problem with it is that it produces a yukky (for lack of a better word) smelling smoke (sulfur dioxide) which is also quite poisonous. BOOK REVIEWS (Log entry 5/5/85) These are my opinions of some of the books I have read on pyrotechnics and explosives. "Fireworks Principles and Practice" by The Reverend Ronald Lancaster M.A. 1972 - This is the best book I have ever seen for the amateur pyrotechnist. It is THE book to have if you want to make your own fireworks. "Pyrotechnics" by George W. Weingart 1947 - Another excellent book. Before the publication of Lancaster's book this was the amateur pyrotechnist's "bible". "The Chemistry of Powder and Explosives" by Tenney L. Davis 1943 - An outstanding text book on explosives with a very good 124 page chapter on pyrotechnics. This has been a personal favorite for years. "Pyrotechnics" by Joseph Howard Mclain 1980 - This is a very technical text book which is not aimed at the do-it-yourselfer. It is well worth having because of its many formulas and descriptions of devices not covered elsewhere in any books I have seen. "Fireworks a History and Celebration" by George Plimpton 1984 - This is not a "how to" book. It is enjoyable light reading about the history of fireworks and some of the author's experiences. For a person who wants to make his own fireworks and is watching his expenses, it is worthless. This is the most expensive and least helpful book I have bought on pyrotechnics. It is completely devoid of practical information. "The Firecracker Cookbook" by Edwin Lough 1983 - A good little book on a subject that is skimpily treated in other books. It contains an excellent formula for flash powder (by weight 70% potassium perchlorate, 30% German black aluminum, .1% chemite). "Professional Homemade Salutes" by Joseph Abrusci 1979 - A fair little book with some useful information. It gives only two formulas for flash powder. One is a dangerous and outdated chlorate mixture and the other is a second rate potassium nitrate composition. It contains some worthwhile information on making cherry bombs. "Chemical Magic" by John Lippy, Jr. date of publication not given - A source of unusual and rare chemical information. Some is related to pyrotechnics. Nearly all is interesting. "Henley's Twentieth Century Book of Ten Thousand Formulas, Processes & Trade Secrets" Edited by Gardner D. Hiscox. Revised 1956 by Harry E. Eisenson. - A massive 867 page chemical recipe book. Not worth bothering about for its pyrotechnic information, but it's a great reference book. "The Poor Man's James Bond" by Kurt Saxon 1972 - A store house of paramilitary and pyrotechnic information including George Weingart's entire book. Great to have as a reference. My only criticisms of the book are that it is printed on cheap newsprint that quickly yellows with age and I find its 11 x 14 1/2 inch format very inconvenient to handle. "Granddad's Wonderful Book of Chemistry" by Kurt Saxon 1975 - A massive reference book defining old chemical terms and describing methods of making your own chemicals. It is printed on the same size and type of paper as his other book. "Improvised Munitions Black Book" Volumes 1, 2, and 3 prepared by the Frankford Arsenal 1963 - 1969 - These are the best of their kind. Their emphasis is paramilitary, but some of the compositions described are interesting from a pyrotechnic viewpoint as well. "Explosives and Propellants From Commonly Available Materials" Desert Publications 1982 - A useful supplement to the "Black Books". "Unconventional Warfare Devices and Techniques Incendiaries" Dept. of the Army Technical Manual TM 31-201-1 1966 - Outstanding coverage of chemical ignition, spontaneous combustion and incendiary mixtures. "Improvised Rocket Motors" Desert Publications 1980 - A poor little volume about making rockets with potassium nitrate and sugar for fuel. Somebody somewhere probably new something about this subject, but they did not get it into this book. "High-Low Boom An Explosives Treatise of Synchronous Historical Duration" by Philip J. Danisevich 1966 - If that pretentious subtitle doesn't make you retch and drop the book, you will find inside a lot of interesting information. The coverage of oxidizer and fuel combinations is particularly good. This book contains a lot of formulas and technical information in a small space. "Kitchen Improvised Plastic Explosives" by Tim Lewis 1983 - An amazing little book giving step by step instructions for making a variety of plastic explosives. "Explosives and Demolitions" Dept. of the Army Field Manual FM 5-25 1967 - Good coverage of the use of military explosives. "The Anarchist Cookbook" by William Powell 1971 - A classic in the science of mayhem. It covers do-it-yourself drugs, explosives, weapons, and traps. It is a vicious book born out of the American underground of the 1960's when a popular pastime on college campuses was "dropping acid" and planning "The Revolution". I keep this book separate from my other books and out of sight. Not to hide it from others, but to avoid seeing it too often myself. It reminds me too much of the days of the Yippies with their motto of "Fuck the System". I knew some of these revolutionary types and they were very depressing people. "Principles of Improvised Explosive Devices" Paladin Press 1984 - Interesting and extensive coverage of electrical means of igniting or detonating incendiary and explosive devices. Contains little else of interest. "British Textbook of Explosives" edited by Donald B. McLean 1969 - Small vaguely interesting book. Not worth bothering with if you have "The Chemistry of Powder and explosives" by Davis. "Improvised Weapons of the American Underground" Reproduced from public domain by Desert Publications. Date of publication not given. - Great if you want to make your own SMG machine gun or silencers. Its explosives information is better covered elsewhere. "CIA Field Expedient Methods for Explosives Preparations" Desert Publications 1977 - A tiny book with a small amount of information not covered elsewhere. Worth having in your library if you are a hard core explosives buff. FLASH SALUTES (Log entry 8/25/85) While attending the OHIO BLAST this weekend, I noticed a guy setting off large salutes that had a tremendous report and extremely bright flash. These were about 3" long by 1" in diameter. They were much brighter than salutes the same size being fired by others. It would be hard to say whether one type was louder than another, but for brilliance of flash these were in a class by themselves. Later, when I got a chance, I asked him about these and got the following formula and directions: Potassium chlorate 5 Magnesium (325 mesh) 2 Antimony trisulfide 1 First mix the magnesium and antimony trisulfide. Pour all the ingredients in the center of a sheet of paper and mix by alternately lifting the corners. The chlorate is used instead of the safer perchlorate to maintain a loud report in the absence of German black aluminum. Another bomb fan told me that this formula will produce an even louder report than the high performance 70:30 mix of potassium perchlorate and German black aluminum: Potassium perchlorate 8 German black aluminum 3 Antimony trisulfide 2 This agrees with information brought back by ----- from the PGII convention in Ithica, NY. ----- also contributed the following variation: Potassium perchlorate 8 German black aluminum 3 Antimony trisulfide 1 Sulfur 1 The improvement is caused by the Antimony trisulfide alone or mixed with sulfur lowering the ignition temperature of the mixture. Of course, this is done at the expense of safety since it makes it more sensitive and dangerous to handle. I got these by phone from -----. The first one is for a very bright flash. Potassium chlorate 1 Powdered magnesium 1 These two, though dangerous formulas, are supposed to be the loudest of all compositions. Potassium chlorate 8 Powdered aluminum 3 Potassium chlorate 8 Powdered aluminum 3 Sulfur 1 I want to note here for the record the original standard formula for M-80's and cherry bombs: Potassium perchlorate 4 Powdered aluminum 1 Antimony trisulfide 1 A 50:50 mix of antimony trisulfide and sulfur can be used for the last ingredient without effecting performance. The old-time standard formula for flash crackers was: Potassium chlorate 2 Powdered aluminum 1 Sulfur 1 Modern authors are unanimous in condemning this formula as too unsafe to use. BENZOATE WHISTLES (Log entry 9/2/85) On August 31, 1985 I tested a whistle composition consisting of Potassium perchlorate/Sodium benzoate in a ratio of 70:30 by weight. I loaded a two ounce and a four ounce rocket case with this composition. Both whistled well for a short time but stopped whistling about half way through the burn. On Sept. 1, 1985 I tested the same formula in a hand rolled casing which was 3/4" I.D. by 4" long. This one generated a piercing whistle which lasted for the full burn time. It was slightly painful to my ears at a distance of 20 paces. BRILLIANT FLARE (Log entry 9/2/85) The following formula loaded into a four ounce rocket case produced a gold colored flare of dazzling brilliance. It was very much brighter than a similar flare using potassium nitrate as the oxidizer. It burns faster than the potassium nitrate composition but more slowly than when potassium perchlorate is used. Sodium nitrate 50 Pyro aluminum 25 Aluminum 50-150 mesh granular 12 1/2 Aluminum 10-14 mesh coarse flitters 12 1/2 Airplane Flare (Log entry 9/5/85) I tested this formula today from Weingart for an airplane flare: Barium nitrate 38 Aluminum 9 Sulfur 2 Petrolatum 1 I made a thin stout casing for the flare by wrapping an 8 1/2" x 4" strip of typing paper around a 1/2" dowel rod and gluing with Elmer's. I used black powder as an igniter. I didn't time it but a 3 1/2" column of this composition burned for about 45 seconds. It produced a brilliant white light that was super bright. Note: Petrolatum is Vaseline. LARGER BENZOATE WHISTLE (Log entry 9/5/85) I loaded a 1" x 4" casing with 70:30 Benzoate whistle composition. This was a poor performer. It whistled briefly then just burned without whistling. The only whistle I have made with this composition that worked properly was the one with an inside diameter of 3/4". CHEMICAL MAGIC (Log entry 9/7/85) These are from my hand written notes taken on March 9, 1980 from a book called "Chemical Magic" by Dr. Leonard A. Ford COLD FIRE: A few ml. will burn in the hand without burning the hand. 60 ml. Carbon disulfide 40 ml. Carbon tetrachloride Cooling by rapid evaporation prevents burning of the hand. FLARE: 5 grams powered aluminum 1/2 gram sodium peroxide Cone of powdered aluminum 1/2 inch high. Sprinkle sodium peroxide loosely over metal and mix slightly into metal. One drop of water releases oxygen from sodium peroxide. Heat of reaction causes powdered aluminum to burn with intense flame. EXPLOSION: Five grain potassium chlorate tablet 10 ml. carbon disulfide 2 grams yellow phosphorus Rapid oxidation of phosphorus in the presence of an oxidizing agent occurs with explosive violence. Place a few drops of a solution of yellow phosphorus in carbon disulfide on the tablet. In 15 minutes the solvent will have evaporated. Touched with a metal rod from a ring stand the explosion is violent. Cut yellow phosphorus under water. FIRE WATER: Glass containing ethyl alcohol Few grams dry, red chromic anhydride The powerful oxidizing agent, chromic anhydride reacts with alcohol. Heat generated results in rapid combustion of the alcohol. On an asbestos sheet, scatter a few crystals of chromic anhydride. When alcohol strikes the chemical an immediate reaction gives rise to flames that rise a foot or more in the air. May be done in a 500 ml. flask. Will burn with a greenish glow. FIRE PAINTING: Long handled brush - 1/8" bristles. Solution of 2 grams white phosphorus dissolved in five times its volume of carbon disulfide. Evaporation of the solvent leaves phosphorus in a finely divided state. This is inflammable at room temperature. Keep brush in water. To clean, rinse first in alcohol then carbon disulfide. RAPID OXIDATION: Four grams ammonium chloride One gram ammonium nitrate Four grams powdered zinc A finely divided metal is quickly oxidized in the presence of a strong oxidizing agent. Dry separately. Mix well. Make slight depression in center of conical pile. One or two drops of water will ignite. Stand well back as water is dropped. SPONTANEOUS FIRE: Powdered aluminum Sodium peroxide Addition of a drop of water to the sodium peroxide generates oxygen. Reaction of the gas with powdered aluminum produces aluminum oxide. The heat generated is great enough to cause the powdered aluminum to burn with such an intense flame that the flash is blinding. After the initial flare the metal continues to glow for some time. On an asbestos mat place a cone of aluminum to a height of 1/2 inch. On top of the metal place a small volume of sodium peroxide. A volume the size of a pea is sufficient. One drop of water starts the reaction. Sodium peroxide is somewhat difficult to handle. ANOTHER SPONTANEOUS FIRE: Five grams ferrous oxalate Paraffin Test tube with cork to fit. Finely divided particles of iron and carbon ignite on exposure to air. Heat ferrous oxalate in the test tube until no more fumes are given off. As the test tube is being heated, you melt paraffin in an evaporating dish. Place the cork in the melted paraffin. While the test tube is still hot, pick up the cork with a tongs. Seal the tube. On cooling, the melted paraffin will make an air-tight seal. Stand on a chair. Sprinkle the contents of the tube in the air. They catch fire in a spectacular display. Five grams lead tartrate can be used in place of ferrous oxalate. Heat the white powder in a test tube until it is black. Then seal with a cork which has been dipped in melted paraffin. TURPENTINE FIRE: Large beaker containing 30 ml. concentrated sulfuric acid and 20 ml. concentrated nitric acid. A few ml. of turpentine. Rapid oxidation of turpentine takes place when the liquid is in contact with the acids. Hold dropper containing the turpentine about 2 feet above beaker. When drops strike the acid, flames rise four to six inches. VOLCANO: 100 grams powdered ammonium dichromate Asbestos mat Filter paper Red hot particles of fluffy chromic oxide are formed on ignition of ammonium dichromate. Some of the reaction product rolls over the sides and some shoots several feet in the air. A two inch roll of filter paper soaked in alcohol is used as a wick. NITROGEN TRIIODIDE AND SILVER FULMINATE (Log entry 9/7/85) These are methods of making nitrogen triiodide and silver fulminate taken from various sources. NITROGEN TRIIODIDE EXPLOSIONS, from "Chemical Magic" by Dr. Leonard A. Ford. Five grams iodine Three grams potassium iodide 20 ml. concentrated ammonium hydroxide Filter paper Funnel Stir the potassium iodide and iodine together in a beaker with 50 ml. of water. Add the ammonium hydroxide with stirring until no more precipitate forms. Filter and spread a thin layer of the wet solid on several filter papers. Break the filter papers into many small pieces and allow to dry for several hours. On drying, the paper is extremely sensitive to touch and will explode violently with the slightest disturbance. Can be safely handled when wet. Do not let any sizeable quantity of the dry material accumulate. Nitrogen triiodide - NH3NI3 NITROGEN TRIODIDE, from "Fireworks & Explosives" published by Pyro-Tech. This substance when dry is so sensitive that a drop of a feather or breath of air will detonate it. Much time and money has been spent in an effort to control its awesome power, but to no avail. If placed in TINY piles in a row and allowed to dry, when touched with a feather or stick they will all explode together from shock. Only SMALL QUANTITIES of this substance should be prepared at a time. Cover a few iodine crystals with concentrated ammonium hydroxide and let sit for about 45 minutes. Filter off the black residue and rinse in cold water. This residue can be kept safely under water in vial - but is extremely dangerous to do so very long because of evaporation. If the water evaporates leaving the crystals to dry - BOOM! When exploded, it leaves a beautiful purple iodine vapor in the air. HOW TO MAKE NITROGEN TRI-IODIDE, from "The Anarchist Cookbook" by William Powell. Probably the most hazardous explosive compound of all is nitrogen tri-iodide. Strangely enough, it is very popular with high school chemists, who do not have the vaguest idea of what they are doing. The reason for its popularity may be the ready availability of the ingredients, but it is so sensitive to friction that a fly landing on it has been know to detonate it. The recipe has only been included as a warning and as a curiosity. It should not be used. Preparation for making nitrogen tri-iodide: 1. Add a small amount of solid iodine crystals to about 20 cc. of concentrated ammonium hydroxide. This operation must be performed very slowly, until a brownish-red precipitate is formed. 2. Now it is filtered through filter paper, and then washed first with alcohol and secondly with ether. Tri-iodide must remain wet, since when it dries it becomes supersensitive to friction, and a slight touch can set it off. This is an extremely unstable compound and should not be experimented with. CONTACT EXPLOSIVE, from "The Firecracker Cookbook" by Edwin Lough. Materials 1. Iodine crystals 2. Pure non-detergent ammonia or ammonium hydroxide. 3. Glass jar with screw-on top. 4. Paper towels. Grind about half a teaspoonful of iodine crystals into a coarse powder, then set it aside. Next, pour about 8 ounces of ammonia into a jar. Add the iodine crystals to the ammonia and cap the jar. Swirl the mixture gently for approximately 10 minutes, then pour the ammonia off slowly so as not to disturb the crystals. Collect the treated crystals (which are the explosive) with a teaspoon and transfer them to a few layers of paper towels. This is done just to remove the excess moisture, for the crystals must remain quite moist to be safe. For storage, transfer the moist crystals into a clean pill vial. They should be used soon after treating, as once they are dry the slightest touch will set them off. The explosive goes off with a loud snapping sound. Some chemists make it a lot more potent by washing the finished product with alcohol, then ether. However, it is much more dangerous to handle this way. Time each batch to see how long it takes to dry. Ten to twenty minutes is about usual. This stuff can be used as a practical joke by putting a small amount on stairways, sidewalks, and similar places. SILVER FULMINATE, from "Fireworks & Explosives" published by Pyro-Tech. This mixture has been used in very small quantities as crackerballs or torpedoes. It is one of the most sensitive mixtures known when dry and many, MANY people have lost limbs, sight or their lives from handling it. For torpedoes, simply fold gently 1 grain of the dry powder into a cone with a few pieces of small sand and twisted at the top. Careful, because when attempting to throw on pavement, it sometimes explodes in your hand from pinching or just the force it takes to throw. Utmost caution must be observed. Professionals won't mess this substance, bear that in mind. Pour 25 ml. denatured ethyl alcohol and 25 ml. concentrated nitric acid all at once over 5 1/2 grams silver nitrate in a flask. A violent reaction ensues and deposits the silver fulminate. Add 125 ml. water to mixture, filter and dry for use. This substance must be stored and dried where light cannot reach it because it is affected by light. USE EXTREME CAUTION with the dry substance as it is HIGHLY SENSITIVE. FULMINATING SILVER: This is also from Pyro-Tech. This appears to be a chemically different and more sensitive compound than silver fulminate. This substance has properties of the nitrogen triodide discussed elsewhere but is sometimes even more sensitive and powerful. Remember, this substance can not be moved or disturbed when dry so use the same caution for it as nitrogen triodide. Pour concentrated ammonium hydroxide over silver oxide in flask. After a moment dark deposit of fulminating silver will form. Filter and wash. When dry it can be detonated by the touch of a long stick and explodes VIOLENTLY so be sure to prepare in small quantities. SILVER FULMINATE, from "Pyrotechnics" by George W. Weingart. To prepare this, take 8 ounces of C.P. nitric acid (42%) and add 2 ounces of water gradually, stirring constantly with a glass rod. Into this put a silver dollar (or 1 ounce of metallic silver). Warm slightly until a brisk reaction takes place. When the silver is completely dissolved allow the solution to cool for 3 minutes. Then add 16 ounces of pure alcohol. Add it all at once quickly and be sure that the vessel containing the solution of the silver is quite large because a violent effervescence will take place. After it subsides add 3 more ounces of alcohol. Let stand for 1/4 to 1/2 hour. A white crystalline precipitate will be found on the bottom of the vessel. This is the fulminate and may be collected on a filter and dried in a shady place. A candy jar may be used for making fulminate but a glass beaker is preferable. The utmost care must be exercised in handling the dry powder as the slightest concussion will cause it to explode with terrific violence. A wooden spoon should be used for removing it from the filter. It should be handle as little as possible and in the smallest practicable quantities. GAS/AIR EXPLOSIVES (Log entry 9/7/85) In 1980 I was experimenting with ways to make small controlled explosions for fun. At that time I was avoiding buying anything from chemical companies because my wife had learned while working at B. Prieser Scientific that they had an agreement with the police to notify them if certain combinations of chemicals were ordered. The kinds of things that would sound the alarm were chemicals that could be used to make explosives or illegal drugs. A particularly successful experiment involved detonating acetylene + oxygen by means of an electric spark. Calcium carbide when wetted with water releases acetylene. Plain drug store variety 3% hydrogen peroxide when mixed with Clorox bleach releases oxygen. I prepared a one gallon can by drilling two small holes in the side half way up from the bottom. I threaded two pieces of insulated wire through the holes and twisted them together on the inside. The bare ends of the wires were spaced 1/8 inch apart to form a spark gap. The other ends of the wires were connected to a rig I made from an automobile ignition coil to generate a spark when a button was pushed. I placed a lid containing 1 teaspoonful of calcium carbide inside the can. I then poured 1/4 cup of hydrogen peroxide into the can in such a way that it did not contact the carbide in the lid. I quickly dumped a teaspoonful of water on the carbide and poured 1/4 cup of Clorox onto the peroxide. I pressed a piece of aluminum foil over the top of the can and set a board on top of it. A friend had invited me to his farm to do this experiment so I gave him the honor of pressing the button. After waiting one minute to give the gases time to build up, I gave him the signal and he hit the button. The resulting explosion must have been more than he expected because he went pale and rushed us into the house with the words, "everybody into the house quick before the sheriff comes". The board was blown into the air. The can split at the seam and unrolled almost flat. The sound was like an aerial salute at close range. The valley echoed in the aftermath like rolling thunder. The following list is from a book called "Explosion and Combustion Processes in Gases": Ignition Limits in Air (%) Lower Upper Methane 5 15 Propane 3.22 12.45 Acetylene 2.5 80 Methyl alcohol 6.72 36.5 Ethyl alcohol 3.28 18.95 Isopropyl alcohol 2.65 --- Diethyl ether 1.85 36.5 Hydrogen 4 74.2 Carbon monoxide 12.5 74.2 Ammonia 15.5 27 Carbon disulphide 1.25 50 Hydrogen sulphide 4.3 45.5 ACETYLENE: Maximum explosive effect is with 7.7% gas with 92.3% air. HYDROGEN: Maximum explosion is with 29% hydrogen in air. CALCIUM CARBIDE (CaC2): Pure carbide will yield 5.83 cubic feet of acetylene per pound. Commercial product is usually 85% pure. PAPIER-MACHE CHERRY BOMBS (Log entry 10/2/85) I now have papier-mache cherry bombs down to a science. They consist of a short, closed cylindrical casing surrounded by papier-mache to form a sphere. They measure 1 1/4 inches in outside diameter. 1/2 teaspoonful (2.375 grams) of flash powder fills them slightly over half full. To make the cylinder, roll a 6 3/4" x 3/4" piece of poster board around a 5/8" dowel rod gluing with Elmer's. When rolled the casing should be close to 3/4" in outside diameter. Glue a poster board disk on each end. When dry, enclose the cylinder in two tablespoonfuls of sopping wet papier-mache. Gradually squeeze out the water with your hands forming it into the desired round shape. When the casing is thoroughly dry, drill a 5/32" hole into it and load the powder by funnel and wire. Glue in a piece of 3/32" fuse with a small amount of hot glue. Finish by spray painting with red paint. The papier-mache is made from newspaper pulped in a blender. No adhesive is added. NOTES ON THE P-80 PYRO-PARTY (Log entry 1/5/86) While preparing for the New Years Eve 1985 Pyro-party, I did some experiments worth documenting. I wanted to make some airplane flares but was out of the fine flake aluminum I normally use in this composition. I substituted 400 mesh 12 micron granular aluminum, but the resulting mixture would not ignite even with a very hot igniter. ----- ----- suggested adding an additional 5% of charcoal to make the mixture more combustible. I tried this and it worked very well when a very hot primer was used. The primer was 50/50 by volume Potassium perchlorate/100-200 mesh magnesium. This primer caused problems with some of the finished flares by flashing explosively and failing to light the flare composition. For future experiments I suggest trying 70/30 by weight Potassium perchlorate/German dark aluminum. This burns very hot and does not flash when pressed. This is the final formula for the flare composition (parts are by weight): Barium nitrate 38 Aluminum (400 mesh, 12 micron granular) 9 Sulfur 2 Air float charcoal 2 Petrolatum (Vaseline) 1 MAGNESIUM FLASH POWDER I tested a 50/50 by weight mixture of Potassium chlorate/325 mesh granular magnesium. This is the fastest burning flash powder I have ever tried. 1/4 teaspoonful of this composition, ignited without confinement by a piece of green fuse, flashed with a loud "pop". The sound was similar to a light bulb dropped on concrete. When confined in a salute casing, the report is comparable to that of the same volume of 70/30 Perchlorate/German dark. A 50/50 mixture of fertilizer grade sodium nitrate/100-200 mesh magnesium was also a very fast burning composition, though not as fast as the chlorate/325 mesh magnesium mixture. STROBE STARS ----- showed up a couple of days before the pyro-party with some fragments left over from making red strobe stars. These were truly spectacular. When a piece of this material was ignited, it smoldered for a few seconds then flashed brilliantly with a deep, clear, red light. The cycle of smoldering and flashing was repeated several times before all the composition was consumed. The effect was very attention grabbing and entertaining. I have begun an intensive study of the literature on these compositions and hope to begin experimenting with them in the near future. The formula for this composition follows: Magnesium (60 mesh, coated with 30% potassium bichromate) Ammonium perchlorate 50 Strontium sulphate 20 Potassium bichromate (stabilizer) 5 additional % The strontium sulphate has to be made by precipitation. One gallon of saturated solution of strontium nitrate is mixed with one gallon of saturated solution of magnesium sulphate (Epson salt). The precipitated strontium sulphate is filtered out using a coffee filter. To make the stars, 25 parts of 10% nitrocellulose solution in acetone is added to 100 parts of the composition. This is kneaded and cut into 9 mm cubes. PRECIPITATION OF STRONTIUM SULPHATE (Log entry 2/8/86) In my first experiment I dissolved 100 grams of strontium nitrate in 1/2 gallon of warm water and 100 grams of magnesium sulphate in a separate container with 1/2 gallon of warm water. When poured together an opaque white precipitate was formed which I filtered out on a coffee filter. After thorough drying in a 175 degree oven, the precipitate weighed 71.5 grams. I used this in a red strobe star composition described by Shimizu and the stars performed as described in his text. To determine whether or not equal parts by weight is the correct ratio for the two ingredients, I dissolved 1 teaspoonful of strontium nitrate in two ounces of the clear solution which remained after the precipitate was removed. No visible precipitate was formed. I repeated the experiment using 1 teaspoonful of magnesium sulphate and 2 ounces of the solution. Again, no visible precipitate was formed. My conclusion is that if a surplus of either ingredient is present it is small enough to be considered negligible. In a second precipitation experiment, I dissolved 100 grams of strontium nitrate and 100 grams of magnesium sulphate in separate 8 ounce cups of hot tap water. When poured into a mixing bowl, the precipitate formed a thick slurry which was difficult to stir. I added 1 additional cup of water and poured it into the coffee filter. While doing this, I sloshed a small amount over the side of the filter. After drying, the precipitate weighed 68 grams. Note: Magnesium sulphate is readily available from drug and grocery stores under the name "Epsom Salt". LOW TEMPERATURE STARS (Log entry 2/8/86) I have tested three formulas described by Dr. Shimizu in "Fireworks: The Art, Science and Technique" as low temperature stars. Low temperature stars have a flame temperature of 1700 - 2200 degrees C. I mixed 100 gram batches of each formula, added 8 grams of water and formed them into pumped stars using star pumps 3/8", 1/2" and 5/8" in diameter. The stars were ignited standing on end on a fire brick by means of a piece of black match held in place with a narrow strip of masking tape. The formulas and my observations are listed below: Red Potassium perchlorate 66 Red gum 13 Lampblack 2 Strontium carbonate 12 PVC 2 Rice starch 5 These produced an adequate but not spectacular red flame when viewed from a distance of 30 feet. Green Potassium perchlorate 47.2 Barium nitrate 28.3 Red gum 14.2 Parlon 4.7 Rice starch 5.6 These burned with a pale green flame. They were the least impressive among the three types tested. According to Lancaster this kind of star produces a beautiful, saturated green when viewed from a distance of 50 meters. Blue Potassium perchlorate 60.8 Red gum 9 Basic copper carbonate 12.3 Parlon 13.1 Rice starch 4.8 These were the "star of the show". They burn with a pale blue flame similar in color to a low current electric arc. I have shown these to three people and each one "ooe'd" and "ah'd" and made a comment about how nice they were. There is something about these stars that strikes an aesthetic chord with viewers. STROBE STAR EXPERIMENTS (Log entry 2/8/86) I tried two formulas based on sulfur. The first is from H. G. Hall in England. The second is one I derived by studying a triangle diagram in "Pyrotechnica VIII". White Sulfur 6 Fine magnesium powder 2 Barium nitrate 3 When pressed into a 1/2" diameter casing this composition would not ignite. I scooped a small amount of loose composition onto the head of a burning match. It smoldered with a low blue flame then flashed brilliantly. A small pile of loose composition was easily ignited. It burned with a low blue flame looking just like burning sulfur and flashed repeatedly at irregular intervals. This mixture has real potential if it can be made to perform dependably. When even a tiny dab of this mixture flashes, it looks like a blob of molten, liquid white light. The effect is spectacular. This is definitely worthy of further experimentation. White (Variation of above formula) Sulfur 9 Fine magnesium powder 7 Barium nitrate 4 Pressed into a 1/2" diameter casing, this composition burned vigorously and continuously without strobing. As an experiment, I mixed the remainder of the first formula with that of the second. The resulting mixture performed just like the second alone -- continuous burning without flashing. STROBE STARS CONTAINING SULPHATES Except where otherwise noted these compositions were mixed with 25% of nitrocellulose lacquer and formed into pumped stars. In each case the magnesium or magnalium were coated with potassium dichromate. The extra potassium dichromate used in the formulas was finely powdered with a marble mortar and pestle before mixing with the other ingredients. The burning rates and strobe frequencies were estimated as well as I could using a tape recorder and stop watch. Red (From "Fireworks: The Art, Science and Technique", Shimizu Magnesium 60 mesh 30 (Substituted 100-200 mesh) Ammonium perchlorate 50 Strontium sulphate 20 Potassium bichromate 5 A 1/2" pumped star burned for 5.5 seconds and strobed about 6 flashes per second with a fairly decent red color. I sent one of these up in the head of a 4 ounce rocket. The brightly flickering star falling in an arc was a pleasing effect but, the red color was not very saturated. Red (From "American Fireworks News" #50 Ammonium perchlorate 50 Magnesium 100-200 mesh 25 Strontium sulphate 25 Potassium dichromate 5 A 1/2" pumped star burned for 14.2 seconds Strobing about 3 flashes per second. The timing of the flashes was somewhat irregular. Color seemed more saturated than the first formula. Red (Derived from triangle diagram in "Pyrotechnica VIII) Magnesium 20 Strontium sulphate 30 Ammonium perchlorate 50 Potassium dichromate 5 Pressed into a 1/2" diameter casing this composition burned vibrationaly but at such a high speed it was almost continuous. When formed into 1/2" pumped stars, it burned for 16.2 seconds strobing at a rate of about 2 flashed per second. I noticed that all of the red strobe formulas increased in flash rate toward the end of the burn. Green (From Shimizu) Magnesium 60 mesh 23 (Substituted 100-200 mesh) Ammonium perchlorate 60 Barium Sulfate 17 Potassium dichromate 5 A 1/2" pumped star burned for 5.2 seconds flashing at a rate of approximately 9 flashes per second. Green (My own experimental variation) Magnesium 100-200 mesh 23 Ammonium perchlorate 50 Barium sulphate 27 Potassium dichromate 5 A 1/2" pumped star burned for 5.3 seconds flashing approximately 3 times per second. This was particularly impressive because the flashes were very bright and had good separation. White (Derived from triangle diagram in "Pyrotechnica VIII) Ammonium perchlorate 60 Barium sulfate 20 Magnalium 60 mesh 20 Potassium dichromate 5 I first pressed the composition dry in a 1/2" in diameter casing to a depth of 1 inch. I primed it on top with about a quarter teaspoonful of Shimizu's ignition composition for twinklers. The one inch column burned for 22 seconds and flashed 20 times giving a strobe rate of close to 1 flash per second. The flashes are bright and pure white. This shows promise for use as a back yard display. As a further experiment, I mixed the composition with nitrocellulose lacquer and formed it into 1/2" pumped stars. Ignited with a piece of black match, one of these stars flashed three times with the flashes separated by about 3 seconds. The star smoldered for about 3 seconds before the first flash occurred. That adds up to a total burn time of 9 seconds. Below is Shimizu's ignition composition for twinklers (his term for strobe stars). When used for coating stars, it is mixed with nitrocellulose lacquer just like the star compositions. I used it dry to light the white strobe composition in a casing and also unsuccessfully in an attempt to light the first sulfur based white strobe mixture above. Ignition Composition for Twinklers Potassium perchlorate 74 Rosin (BL combustion agent or Accroides Resin) 12 (Used Accroides Resin) Hemp coal or Paulownia coal 6 (Substituted air float charcoal) Aluminum (fine flake) 3 Potassium bichromate 5 COATING METAL POWDERS WITH POTASSIUM DICHROMATE (Log entry 2/8/86) This is how I prepare small batches of coated magnesium or magnalium for use in ammonium perchlorate strobe stars. Put 100 grams of the metal powder in an aluminum can. I got mine from a can of Armour Chile. Heat in an oven to about 200 degrees F. for 1/2 hour. Heat about a cup of water to boiling in a sauce pan. Place 5 grams of potassium dichromate in a measuring cup. Take the can of powder from the oven. Pour 30 cc's of boiling water onto the potassium dichromate and stir to dissolve. Pour the dichromate solution onto the metal powder and stir until it is evenly distributed. Spread the damp powder on a sheet of kraft paper from a large grocery bag. Dry in the oven at reduced heat (150-175 degrees F.). Remember to wear eye and respiratory protection when handling potassium dichromate. SIDE BY SIDE TESTS OF BLUE COMPOSITIONS (Log entry 2/9/86) Blue Star I ("Fireworks: The Art, Science and Technique") Potassium perchlorate 60.8 Accroides resin 9 Basic copper carbonate 12.3 Parlon 13.1 Rice starch 4.8 Moistened with 8% addition of water. Formed into 1/2" pumped stars. Burning time was 9.2 seconds. This gave the pleasing blue flame described earlier. I also pressed some of this composition dry in a 1/2 inch casing to a depth of 1/2 inch. The burn time was 12 seconds. At first the color of the flame was badly disturbed by the burning of the top part of the casing. After this burned away the color was the same as the pumped star. Blue Star II ("Fireworks: The Art, Science and Technique") Potassium perchlorate 66.5 Accroides resin 9.9 Cupric oxide 13.4 Parlon 5.4 Rice starch 4.8 Moistened with 12% addition of water. A 1/2" pumped star burned in 5 seconds. The flame was bluish white. Ammonium perchlorate blue star (Pyrotechnica I) Ammonium perchlorate 70 Red Gum 10 Copper carbonate 10 Dextrin 5 Charcoal 10 Moistened with 4 cc's of 91% isopropyl alcohol to 25 grams of composition. These stars burn so quickly, I burned a second one to get another look. Burn time was 2.7 seconds. The blue color is very weak but, these stars throw off a shower of sparks. I believe they would be impressive in the air. Blue colored fire ("Fireworks Principles and Practice", Lancaster) Ammonium perchlorate 30 Potassium perchlorate 40 Basic copper carbonate 15 Accaroides resin 15 I pressed this composition dry in a 1/2 inch casing to a depth of 1/2 inch. I didn't get the exact burn time on this one. It burned vigorously for about 5 seconds. The blue color was weak. Experimental blue formula Potassium perchlorate 60 Accroides resin 9 Copper sulfate 13 Parlon 13 Rice starch 5 This is basically the same formula as Blue star #I except that I have replaced the copper carbonate with copper sulfate. I was looking for a good blue and with this formula I found it. The burn time was 20 seconds for 1/2 inch of composition pressed dry in a 1/2 inch casing. The flame color was a nice saturated blue. The best tested so far. Shimizu warns that copper sulphate is a highly acid salt and should not be used with chlorates. It is also toxic. REC.PYROTECHNICS FAQ ++++++++++++++++++++ CONTENTS ======== 1. Introduction - Welcome to rec.pyrotechnics 2. Reading rec.pyrotechnics 3. Posting to rec.pyrotechnics 4. Legal Aspects of Pyrotechnics 5. PGI - Pyrotechnics Guild International 6. Pyrotechnic Literature 6a. Fireworks Literature 6b. Fringe Literature 6c. Net-Available Information 7. Frequently Asked Questions 7a. Nitrogen Tri-Iodide, NH3.NI3 7b. Thermite 7c. Dry Ice Bombs 7d. Smoke Bombs 7e. Basic Pyrotechnic Devices 7f. Terminator Bombs, MacGyver, etc. 8. Commonly Used Chemicals in Pyrotechnics 1. Introduction - Welcome to rec.pyrotechnics ============================================= Rec.pyrotechnics is a worldwide newsgroup dedicated to the discussion of fireworks and explosives, mostly concerned with their construction. The readers of rec.pyrotechnics welcome anyone with an interest in the subject, be they experienced or just trying to get started in the hobby. If you are just getting started, try to get hold of as much information on the subject as you can, and read it carefully. If it is explosives you are interested in, make sure you read up on the theory behind explosives. There is a lot of misinformation in movies etc. regarding explosives, so it is important you get a good background from a reliable source. In the Pyrotechnic Literature section below are several books that are must-reads for anyone serious about pyrotechnics. Try all your local libraries - even if they don't have the books mentioned below, they are sure to have some information on the subject. Remember, you can never be too well-informed - it is *your* safety that is at stake, and not being aware of all the aspects involved is extremely dangerous. Pyrotechnics and explosives are not safe - factories have been destroyed in the past, and they have access to the best materials and equipment, and take the most stringent safety precautions. Some people on the net have also been injured by accidents, and many of them had years of experience and took extremely comprehensive safety measures. Some knowledge of chemistry and physics is essential - if you didn't do high-school chemistry, get yourself a chemistry textbook and read it. Make sure you understand the basic principles involved for any composition you might be making. It is a good idea to check a recipe out with someone who is experienced in chemistry, to make sure you haven't missed any safety aspect. If you take the time to find out all the information, and put safety of yourself and others as your highest priority, you will find pyrotechnics an extremely fun and rewarding hobby. 2. Reading rec.pyrotechnics =========================== Often you will see an interesting composition or method posted to rec.pyrotechnics and the temptation is to run out and try it immediately. However, sometimes information posted will contain errors, or omit important safety aspects. Sometimes people will post methods that they heard from some vague source, or that they think should work but haven't tried. Leave it for a couple of days to see if anyone on the net responds to it. If not, get a printout of it and read it several times to make sure you are completely familiar with it. If you have any questions or corrections for an article, please don't hesitate to post. People on the net would much rather answer a question that may seem "silly" to you, than to have you get hurt. 3. Posting to rec.pyrotechnics ============================== If you have a composition or a method that has served you well, please share it with the net. Also if you have a question, people will be happy to help you out with it. However, please remember that you message is going to be read by a lot of people around the world, many of whom may not be as familiar with aspects of your posting as you are. Include all relevant safety information, for example possible mixing and storage hazards, toxicity, expected behaviour of the composition once ignited etc. If you post something you haven't tried, be sure to make that clear in your article. This is a good idea when asking questions as well - make sure it is obvious that you are asking a question, rather than posting something you don't know about and hoping someone will correct it. Read through your article before posting it to make sure that you have covered every aspect, and that there are no errors or ambiguities that could cause people to interpret part of it the wrong way. 4. Legal Aspects of Pyrotechnics ================================ Chances are that many of the procedures involved in pyrotechnics are illegal without a permit where you live. There are generally separate laws regarding storage of chemicals, manufacture of fireworks, manufacture of explosives, storage of fireworks, storage of explosives, use of fireworks and use of explosives. The laws regarding fireworks may also be split up in terms of the "Class" of fireworks concerned - commonly available fireworks are Class C, while the fireworks typically seen at displays will be mainly Class B, with some Class C. Make sure you know where you stand in terms of the law in your area, and get a permit if necessary. Make sure that what you are doing will not cause any damage to other people's property, and that there are no innocent bystanders that can get hurt. There are plenty of laws relating to injury or damage to third parties and their property, not to mention lawsuits. We don't want anyone to get in trouble with the law because of anything here. 5. PGI - Pyrotechnics Guild International ========================================= Pyrotechnics Guild International, Inc is a non-profit organization of professional and amateur fireworks enthusiasts: builders, shooters & watchers. Membership includes a quarterly journal and an annual convention. (Idaho (Fire) Falls, Idaho, 92) For membership information, contact: PGI Ed Vanasek 18021 Baseline Ave Jordan, MN 55352 You need either three reccomendations from random people or one reccomendation from a PGI member. Dues are $25/yr., US. Another newsletter is American Fireworks News, monthly, miscellaneous news, technical articles, ads, $19.95/yr. AFN Star Rt Box 30 Dingmans Ferry, PA 18328 6. Pyrotechnic Literature ========================= 6a. Fireworks Literature ------------------------ These are extremely good books on the subject of pyrotechnics, and are really a must-read for the serious pyrotechnics enthusiast. Many others that are not listed here are also worth reading - check out your local library, Books In Print, Pyrotechnica Publications etc. for more references. Conkling, John A.: "Chemistry of Pyrotechnics: Basic Principles & Theory" (Marcel Dekker, New York, NY 1986. (ISBN 0-8247-7443-4).) See also Conkling's articles in Scientific American (July 1990, pp96-102) and Chemical & Engineering News (June 29, 1981, pp24-32). Shimizu, Takeo: "Fireworks - The Art, Science and Technique", 2nd ed. (Pyrotechnica Publications, 1988. (ISBN 0-929388-04-6).) Lancaster, Ronald: "Fireworks, Principles and Practice" (Illus.) 2nd ed. (Chemical Publishing Company Incorporated, 1992. (ISBN 0-8206-0339-2).) The 1st edition is also available, and is much cheaper. The 2nd edition only has about 20 new pages and some minor corrections, but is about $50 more expensive. Shimizu often directs people to Lancaster rather than giving the detailed information himself. Weingart, George W.: "Pyrotechnics" (Illus.) (Chemical Publishing Company Incorporated, 1968. (ISBN 0-8206-0112-8).) Davis, Tenney L.: "Chemistry of Powder and Explosives" More references are available from Books In Print. By far the best source for all books on fireworks is: Pyrotechnica Publications 2302 Tower Drive Austin, TX 78703 USA 6b. Fringe Literature --------------------- These books usually deal with home-made explosives etc. more than fireworks, and are usually dubious at best. Most are not worth buying, especially if you are more interested in the pyrotechnics field. Much of the information in them is inherently unsafe - many of the books deal with field-expedient methods, and assume that some casualties are acceptable along the way. If you want to try anything out of one of these, it is a good idea to ask about it on the net or to someone experienced in pyrotechnics or explosives. "The Anarchist's Cookbook": this is in "Books in Print" so your local bookstore should be able to get you a copy. Alternatively, you can send $22 (includes postage) to Barricade Books, PO Box 1401, Secaucus NJ 07096. The Anarchist's Cookbook gets a big thumbs down because it is full of inaccurate information. "Ragnar's Guide to Home and Recreational Use of High Explosives": thumbs down as it is even more inaccurate than The Anarchist's Cookbook. US Army Technical Manual 31-210 1969 "Improvised Munitions Handbook": The Improvised Munitions Handbook generally gets okay reviews; it contains a whole bunch of recipes for making explosives etc. out of handy chemicals. You can get it from several sources, gun shows, or for $5 from Sierra Supply. "Poor Man's James Bond Vol. 2": mostly a set of reprints of various books, in small type. It does have Davis' Chem. of Powder and Explosives and what appears to be Vol. 1 and 2 of the Improvised Munitions Handbook series. Vol. 1 of PMJB has a reprint of Weingart's book Pyrotechnics (?) Here are some sources for the books. Most of these places will send you a catalog with related material. Loompanics, P.O. Box 1197 Port Townsend, WA 98368. This company sells a wide selection of fringe books on drugs, explosives, war, survival, etc. Catalog $5. Sierra Supply, PO Box 1390 Durango, CO 81302 (303)-259-1822. Sierra sells a bunch of army surplus stuff, including technical manuals such as the Improvised Munitions Handbook. Sierra has a $10 minimum order + $4 postage. Catalog $1. Paladin Press, P.O. Box 1307 Boulder, CO 80306 Delta Press Ltd, P.O. Box 1625 Dept. 893 El Dorado, AR 71731 Phoenix Systems, P.O. Box 3339, Evergreen CO 80439 Phoenix carries fuse (50 ft/$9), smoke grenades, tracer ammo, dummy grenades. Catalog $3. U.S. Cavalry, 2855 Centennial Ave. Radcliff, KY 40160-9000 (502)351-1164 Sells all kinds of military and adventure equipment. Thanks to Ken Shirriff, Phil Ngai, Keith Wheeler, Charles Marshall, Gary Hughes, and others. 6c. Net-Available Information ----------------------------- The so-called "gopher files", a collection of 4 introductory files on pyrotechnics, are available using a file transfer client called gopher. The sources for gopher are available via anonymous FTP from boombox.micro.umn.edu in the directory /pub/gopher/ . You can see what it looks like by telneting to consultant.micro.umn.edu and logging in as "gopher". The pyroguide is in the Gopher system under: Other Gopher and Information Servers/Fun & Games/Recipes/Misc/Pyrotechnics These files are quite a good introduction to pyrotechnics, including information on the manufacture of fuses and casings. "The Big Book Of Mischief 1.3", commonly abbreviated TBBOM, is available via anonymous FTP from world.std.com, and has the file path: obi/Mischief/tbbom13.txt.Z This is generally a compilation of articles from many sources such as 'The Poor Man's James Bond' and from here in rec.pyrotechnics. This also comes under the heading of 'Fringe Literature', as many of the items and methods contained in it are of dubious safety and reliability. 7. Frequently Asked Questions ============================= Below are descriptions of several things that are frequently asked about on rec.pyrotechnics - they are not generally of much use in fireworks, but they are here to cut down message traffic on these subjects which have been covered many times before. First though, here are some safety rules. Read these and memorize them. 1. Mix only small batches, especially when trying something out for the first time. Some mixtures, particularly flash powder, will detonate rather than deflagrate (just burn) if enough is present to be self- confining. It doesn't take much to do this. Small amounts of unconfined pyrotechnic mixtures may damage your hands, eyes or face. Larger amounts can threaten arms, legs and life. The hazards are greatly reduced by using smaller amounts. Also be aware that a mixture using finer powders will generally behave MUCH more vigorously than the same mixture made with coarser ingredients. Many of these mixtures are MUCH more powerful than comparable amounts of black powder. Black powder is among the tamest of the pyrotechnician's mixtures. 2. Many of these mixtures are corrosive, many are very toxic, some will react strongly with nearly any metal to form much more unstable compounds. Of the toxics, nearly all organic nitrates have *very* potent vasodilator (heart and circulatory system) effects. Doses for heart patients are typically in the small milligram range. Some can be absorbed through the skin. 3. Keep your work area clean and tidy. Dispose of any spilled chemicals immediately. Don't leave open containers of chemicals on your table, since accidental spillage or mixing may occur. Use only clean equipment. 4. If chemicals need to be ground, grind them separately, never together. Thoroughly wash and clean equipment before grinding another chemical. 5. Mixing should be done outdoors, away from flammable structures, and where ventilation is good. Chemicals should not be mixed in metal or glass containers to prevent a shrapnel hazard. Wooden containers are best, to avoid static. Always use a wooden implement for stirring. Powdered mixtures may be mixed by placing them on a sheet of paper and rolling them across the sheet by lifting the sides and corners one at a time. 6. Don't store powdered mixtures, in general. If a mixture is to be stored, keep it away from heat sources, in cardboard or plastic containers. Keep all chemicals away from children or pets. 7. Be sure all stoppers or caps, especially screw tops, are thoroughly clean. Traces of mixture caught between the cap and the container can be ignited by friction from opening or closing the container. 8. Always wear a face shield, or at least shatterproof safety glasses. Also wear a dust mask when handling powdered chemicals. Particulate matter in the lungs can cause severe respiratory problems later in life. Wear gloves and a lab apron when handling chemicals. This rule is very important. 9. Make sure there are no ignition sources near where you are working. This includes heaters, motors and stove pilot lights. Above all, DON'T SMOKE! 10. Have a source of water READILY available. A fire extinguisher is best, a bucket of water is the bare minimum. 11. Never, under any circumstances, use metal or glass casings for fireworks. Metal and glass shrapnel can travel a long way, through body parts that you'd rather they didn't. 12. Always be thoroughly familiar with the chemicals you are using. Don't just rely on the information provided with the recipe. Look for extra information - the Merck Index is very good for this, especially regarding toxicity. It can also provide pointers to journal articles about the chemical. 13. Wash up carefully after handling chemicals. Don't forget to wash your ears and your nose. 14. If a device you build fails to work, leave it alone for half an hour, then bury it. Commercial stuff can be soaked in water for 30 minutes after being left for 30, then after 24 hours cautious disassembly can be a valid learning experience. People have found "duds" from shoots that took place over a year ago, having been exposed to rain etc, which STILL functioned when fitted with fresh fuse or disposed of in a bonfire. Even after a 30 minute waiting period (minimum), initial pickup should be with a long- handled shovel. 15. Treat all chemicals and mixtures with respect. Don't drop them or handle them roughly. Treat everything as if it may be friction- or shock-sensitive. Always expect an accident and prepare accordingly, even if all these safety precautions are observed. Several people on the net have gotten stitches, lost fingers, or been severely burned. Some of them were very scrupulous in their safety precautions and had many years' safe experience with pyrotechnics. 7a. Nitrogen Tri-Iodide, NI3.NH3 -------------------------------- Nitrogen Tri-Iodide is a very unstable compound that decomposes explosively with the slightest provocation. It is too unstable to have any practical uses, but is often made for its novelty value. Some books describe uses for it in practical jokes etc. but in my experience it has been far too unstable for this to be a feasible idea. Despite its common name, the explosive compound is actually a complex between nitrogen tri-iodide and ammonia, NI3.NH3 (nitrogen tri-iodide monamine). Reagents: Solid Iodine (I2) Ammonia solution (NH4OH) - Use only pure, clear ammonia. Other solutions, such as supermarket 'cloudy' ammonia, will not give the desired product. Place a few fine crystals of iodine in a filter paper. The best way to make fine iodine crystals is to dissolve the iodine in a small quantity of hot methanol (care: methanol is toxic and flammable. Heat on a steam bath away from open flame. Use in a well-ventilated area.), and then pour the solution into a container of ice-cold water. This will cause extremely fine iodine crystals to precipitate out. Drain off the liquid and wash the crystals with cold water. If this method is not possible, crush the iodine as finely as possible. Then filter ammonia through the iodine crystals. Use a small amount of ammonia and refilter it, to reduce wastage. The smaller the pieces of iodine the better the result, as more iodine will react if it has a greater surface area. You will be able to recognise the NI3.NH3 by its black colour, as opposed to the metallic purple of the iodine. Reaction: 3I + 5NH OH ---> 3NH I + NI .NH + 5H O 2(s) 4 (aq) 4 (aq) 3 3(s) 2 (l) When the NI3.NH3 decomposes it will leave brown or purple iodine stains. These are difficult to remove normally, but can be removed with sodium thiosulphate solution (photographic hypo). They will fade with time as the iodine sublimes. Safety aspects: NI3.NH3: Despite the common misconception presented in many articles on NI3.NH3, it is NOT safe when wet. I have personally witnessed NI3.NH3 exploding while at the bottom of a 1000Ml plastic beaker full of water. NI3.NH3 can not be relied on not to decompose at any time. Even the action of air wafting past it can set it off. If you want to dispose of some NI3.NH3 once you have made it, it can be reacted safely with sodium hydroxide solution. NI3.NH3 is a potent high explosive, and should be treated with respect. Its power, instability and unpredictability require that only small batches be made. Do not make more than you can immediately use. Never attempt to store NI3.NH3. The detonation of NI3.NH3 releases iodine as a purple mist or vapour. This is toxic, so avoid breathing it. Toxicity data on NI3.NH3 is unknown, but I think it is safe to assume that eating or touching it would be a bad idea anyway. Iodine: Iodine sublimes easily at room temperature and is toxic - ingestion of 2-4g of iodine can be fatal. Make sure you are in a well-ventilated area, and avoid touching the iodine directly. Ammonia: Again, use in a well-ventilated area as ammonia is not particularly pleasant to inhale. Ammonia is corrosive, so avoid skin contact, especially if using relatively concentrated solution. If skin contact occurs, wash off with water. Don't drink it. 7b. Thermite ------------ The thermite reaction is a redox reaction that produces a lot of heat and light. In its usual configuration, temperatures can exceed 3000 degrees C, and molten iron is produced. It is therefore mainly used for welding, and by the Army in incendiary grenades. There are many possible configurations - basically it is the reaction between a reactive metal and the oxide of a less reactive metal. The most common is as follows: Aluminium powder, Al (coarse) 1 volume part or 3 weight parts Iron (III) Oxide, Fe203 1 volume part or 1 weight part A stoichiometric mixture will provide best results. The powders are mixed together and ignited with a suitable fuse. Many people use magnesium ribbon - I don't recommend this, as magnesium ribbon is not all that easy to light, and quite prone to going out due to oxygen starvation. A much better fuse for thermite is a common sparkler. The mixture should be shielded with aluminium foil or similar to prevent sparks from the sparkler igniting the thermite prematurely. Reaction: 2Al + Fe O ---> Al O + 2Fe + lots of heat (s) 2 3(s) 2 3(s) (l) The mixture can be varied easily, as long as the metal oxide you are using is of a less reactive metal than the elemental one you are using, e.g. copper oxide and zinc. Adjust the ratios accordingly. Safety aspects: Reaction: Make sure you no longer need whatever you are igniting the thermite on - the reaction will melt and/or ignite just about anything. If you ignite the thermite on the ground, make sure the ground is DRY and free of flammable material. If the ground is wet a burst of steam may occur, scattering 3000 degree metal everywhere. Be careful when igniting the thermite - use adequate shielding to prevent premature ignition. Don't get close to the mixture once ignited - it has been known to spark and splatter. Don't look at the reaction directly. It produces large amounts of ultraviolet light that can damage the eyes. Use welder's goggles, 100% UV filter sunglasses or do not look at all. Aluminium: Chemical dust in the lungs is to be avoided. As always, wear a dust mask. Make sure the environment you are working in is dry - aluminium powder can be dangerous when wet. Fine aluminium dust is pyrophoric - this means it can spontaneously ignite in air. For this reason aluminium powder with a large particle size is recommended. Iron Oxide: This is not directly toxic, but any particulate matter in the lungs is not good. Again, the dust mask is important. 7c. Dry Ice Bombs ----------------- Dry ice bombs are devices that use pressure to burst a container, producing a loud report and limited shock effects. No chemical reaction is involved - the container, usually a plastic 2-litre soft drink bottle, is burst by the physical reaction of solid carbon dioxide, CO2, subliming into gas. As the CO2 sublimes, the pressure builds up and eventually the container ruptures. The method is very simple - some dry ice is added to the container, some water is added (about 1/3-1/4 full) and the cap is screwed on tight. Within a short time the container will burst, usually extremely loudly. The water can be omitted if a longer delay time is required. It is reported that these devices can be manufactured using liquid nitrogen instead of dry ice, and no water. This is not recommended as the delay time will be substantially shorter. Safety aspects: Device: NEVER use glass or metal containers! I cannot stress this enough. Dry ice bombs are extremely unpredictable as to when they will go off, and a glass or metal container is very very dangerous to both the constructor and anyone else in the vicinity. Plastic bottles are much safer because the fragments slow down quicker, and thus have a smaller danger radius around the device. Plastic fragments are still very nasty though - don't treat the device with any less caution just because it is made of plastic. There is no way to tell how long you have until the dry ice bomb explodes - it can be anywhere from a few seconds to half an hour. Never add the water or screw the cap on the container until you are at the site you want to use it and you are ready to get away. Never go near a dry ice bomb after it has been capped. If a dry ice bomb fails to go off, puncture it from long range with a slingshot, BB gun, by throwing stones at it or similar. Some indication of timing can be achieved by semi-crushing the container before capping - once the container has expanded back to its original shape it is no longer safe to be anywhere near. Don't forget that the temperature of the day and the size of the dry ice pieces will affect the delay length - don't assume that delay times will be similar between bombs. A hotter day or smaller pieces of dry ice (i.e. greater surface area) will create a shorter delay. Remember, even though no chemical reaction occurs you can still be legally charged with constructing a bomb. Dry Ice: Humans will suffocate in an atmosphere with a carbon dioxide concentration of 10% or more. Use in a well-ventilated area. Dry ice typically has a temperature of about -75 degrees C, so do not allow it to come into contact with the skin, as freezer burns and frostbite will occur. Always use gloves or tongs when handling dry ice. 7d. Smoke Bombs --------------- A relatively cheap and simple smoke mixture is potassium nitrate (saltpetre) and sugar. The mixture can be used in powder form, but much better results are achieved by melting the components together. The mixture should be heated slowly until it just melts - beware of excessive heating as the mixture will ignite. Keep a bucket of water next to you in case the mixture does ignite, and peform the entire operation outdoors if possible. The mixture does not have to be completely liquid, the point at which it has about the viscosity of tar or cold honey is about right. While it is semi-liquid it can be poured into cardboard or clay molds, and a fuse inserted. Once it cools and hardens it will be similar to a stick of hard candy, hence its common name of "caramel candy". Safety aspects: Mixture: The mixture burns very hot. Don't go near it once ignited, and don't assume that whatever the mixture is contained in or standing on will survive. Try not to breathe the smoke as fine particles in the lungs are not good for them. 7e. Basic Pyrotechnic Devices ----------------------------- Stars ----- A star is an amount of pyrotechnic composition that has by some means been fashioned into a solid object. These are the bright burning objects you see ejected from Roman candles, shells, mines etc. Usually the pyrotechnic composition is mixed with a binder and a small amount of solvent to make a doughy mass which is then fashioned into stars, although some use has been made of so-called pressed stars, which involve the composition being pressed extremely hard into a mold with a hydraulic press or similar, thus doing without the solvent. The usual methods are to make the composition into a flat pancake or sausage and cut it up into stars ("cut stars"), pushing it through a tube with a dowel, cutting it off at regular intervals ("pumped stars") or rolling cores of lead shot coated in fire clay in a bowl of the composition ("rolled stars"). Cutting and pumping produce cubic or cylindrical stars, while rolling produces spherical stars. Pumped stars are the most suitable for Roman candles, because it is easy to get the correct width. The stars are often dusted with a primer, usually meal black powder, to ensure ignition. Shell ----- The shell is a sphere or cylinder of papier mache or plastic which contains stars and a bursting charge, together with a fuse. It is fired into the air from a tube using a lift charge, usually black powder. The time the fuse takes determines the height above the ground at which the shell will burst, igniting and spreading the stars. Rocket ------ A rocket consists of a tube of rocket fuel, sealed at one end, with a constriction, or nozzle, at the other end. The burning fuel produces exhaust gases, which, when forced out the nozzle, produce thrust, moving the rocket in the other direction. Solid fuel rockets can be one of two types - end-burning, where the fuel is solidly packed into the tube, so the fuel can only burn at one end - and core-burning, where there is a central core longitudinally through the fuel, so the fuel can burn down its full length. At the top of the rocket can be a smoke composition, so it is possible to determine the maximum height ("apogee") of the rocket, or a burst charge and stars. Lance ----- A lance is a thin paper tube containing a pyrotechnic composition. These are most commonly used in large numbers to make writing and pictures at fireworks shows - this is referred to as lancework. The tube is thin so burns completely away as the lance burns, so as not to restrict light emission from the burning section. Gerb ---- These are pyrotechnic sprays, often referred to as fountains or flower- pots. They consist of a tube full of composition, sealed at one end and with a nozzle at the other, similar to a rocket. Unlike a rocket, they are not designed to move anywhere, so all the emphasis is on making the nozzle exhaust as long as pretty as possible, with large amounts of sparks, nice colours etc. The sparks are produced by metal powders or coarse charcoal in the gerb composition, with coarse titanium powder being the chemical of choice. Gerb compositions in a thin tube set up in a spiral arrangement are used as wheel drivers, for spinning fireworks e.g. Catherine wheels. Waterfall --------- These are similar to gerbs, but usually do not spray as far. They are usually mounted horizontally in banks of several tubes, placed some distance above the ground. When ignited, the effect is like a brilliant waterfall of sparks. Mine ---- These have a mortar arrangement similar to that for a shell, but are not designed to send out a shell. The lift charge sends up a bag full of stars and a bursting charge, with a short fuse set to spread the stars relatively close to the ground. Because the bag has much less strength than a shell, the stars are not spread as far, and the final effect is that of a shower of stars moving upward in an inverted cone formation. 7f. Terminator Bombs, MacGyver, etc. ------------------------------------ The first thing to remember when watching pyrotechnics in movies, TV shows etc. is that it is exactly that, not real life. There is almost always no point in trying to extrapolate what MacGyver, for example, does back to reality, with respect to pyrotechnics at least. Reese making those bombs from supermarket supplies in Terminator was bogus, as are pretty much any information on explosives you receive from movies. Sorry. 8. Commonly Used Chemicals in Pyrotechnics ========================================== Ignitibility and Reactivity --------------------------- The secret of making a good pyrotechnic mixture is _homogeneity_. The better the contact with the oxidiser and the fuel is, the fiercer the composition. Finely ground fuels and oxidisers are essential for good stars and propellants. The required intimacy also implies that mixing can never be thorough enough. For consistent results, use the same sieves and same mixing methods. Wet mixing is sometimes more efficient than stirring the dry composition; moreover, it is almost always safer. Star compositions and granulated powders can almost always be mixed with water or some other solvent. Good, homogenous compositions also ignite more easily. Large amounts of loose, fine powder of almost any pyrotechnic composition represent a large fire and explosion hazard. But when such a powder is kneaded and cut into stars or carefully pressed in a tube, it will take fire easily and burn smoothly. This is the pyrotechnist's dilemma: the best compositions are often the most dangerous ones, too. But not always. There are chemicals and compositions with much worse safety records than today's compositions have. In the list of pyrotechnic chemicals below, the most notorious ones have been indicated. Aluminium, Al -- Fuel This is used in many compositions to produce bright white sparks or a a bright white flame. There are many grades of aluminium available for different spark effects. Most pyrotechnic compositions that involve sparks use aluminium, e.g. sparklers, waterfalls etc. Ammonium Nitrate, NH4NO3 -- Oxidiser This is used very infrequently in pyrotechnics due to its hygroscopic nature and the fact that it decomposes even at relatively low temperatures. Even when dry, it reacts with Al, Zn, Pb, Sb, Bi, Ni, Cu, Ag and Cd. In the presence of moisture it reacts with Fe. It reacts with Cu to form a brissant and sensitive compound. It is best not to use any bronze or brass tools when working with ammonium nitrate. Ammonium perchlorate, NH4ClO4 -- Oxidiser Used as an oxidiser in solid rocket fuels, most notably the solid booster rockets for the Space Shuttle. Using it in a composition improves the production of rich blues and reds in the flames. As with any ammonium salt, it should not be mixed with chlorates due to the possible formation of ammonium chlorate, a powerful and unstable explosive. Anthracene, C14H10 -- Smoke Ingredient Used in combination with potassium perchlorate to produce black smokes. Antimony, Sb -- Fuel The metal is commonly used in the trade as 200-300 mesh powder. It is mainly used with potassium nitrate and sulphur, to produce white fires. It is also responsible in part for the glitter effect seen in some fireworks. Antimony trisulphide, SbS3 -- Fuel This is used to sharpen the reports of pyrotechnic noisemakers, e.g. salutes. It is toxic and quite messy. Barium salts -- Colouring Agents Used to colour fires green. several are used: Barium carbonate, BaCO3 -- Colouring Agent, Stabilizer As well as being a green flame-colourer, barium carbonate acts as a neutralizer to keep potentially dangerous acid levels down in pyrotechnic compositions. Barium chlorate, Ba(ClO3)2.H2O -- Colouring Agent, Oxidiser Used when deep green colours are needed. It is one of the more sensitive chemicals which are still used, best to avoid if possible, but if used it should be in combination with chemicals which will reduce its sensitivity. Barium nitrate, Ba(NO3)2 -- Colouring Agent/Enhancer, Oxidiser Not very strong green effect. Used with aluminium powder to produce silver effects. Below 1000C aluminium burns silvery-gold, characteristic of aluminium-gunpowder compositions. Above 1000C it burns silver, and may be achieved using barium nitrate. Boric acid should always be used in compositions containing barium nitrate and aluminium. Barium oxalate, BaC2O4 -- Colouring Agent Sometimes used, generally in specialised items with magnesium. Boric acid, H3BO3 -- Stabilizer This is a weak acid, often included in mixtures that are sensitive to basic conditions, notably those containing aluminium. Calcium carbonate, CaCO3 -- Stabilizer Used as a neutralizer in mixtures that are sensitive to both acids and bases, for example chlorate/aluminium flashpowder. Calcium oxalate, CaC2O4 -- Colour Enhancer Used to add depth to colours produced by other metal salts. Carbon black/Lampblack, C -- Fuel A very fine form of carbon made by incompletely burning hydrocarbon fuels. Commonly used in gerbs to produce bright orange sparks. Charcoal, C -- Fuel Probably the most common fuel in firework manufacture, it is not pure carbon and may contain in excess of 10% hydrocarbons. Indeed, the purer carbon charcoals (e.g. activated charcoal) do not necessarily give better results, and are very often worse than less pure grades. It is included in the vast majority of pyrotechnic compositions in various mesh sizes and grades, or as a component of black gunpowder. Clay This is an important material for making fireworks, not as a reagent but to perform various practical applications such as blocking or constricting the ends of tubes for crackers or rocket nozzles, or coating lead shot prior to the application of star composition when making rolled stars. Copper and copper compounds -- Colouring Agents Used to add both green and blue colours to flames: Copper metal, Cu -- Colouring Agent Both the bronze and electrolytic forms are occasionally used, but easier methods are available for the same effect. Copper acetoarsenate, C4H6As6Cu4O16 -- Colouring Agent Commonly called Paris Green, this chemical is toxic but used to produce some of the best blue colours in combination with potassium perchlorate. Copper carbonate, CuCO3 -- Colouring Agent This is the best copper compound for use with ammonium perchlorate for production of blue colours. Also used in other blue compositions. Copper (I) chloride, CuCl -- Colouring Agent Cuprous chloride is probably the best copper compound for creating blue and turquoise flames, and it can be used with a variety of oxidizers. It is non-hygroscopic and insoluble in water, but it is oxidised slowly in air. Copper oxides, CuO/Cu2O -- Colouring Agent Used for many years for blues, but needed mercury chloride to intensify colours. Seldom used. Copper oxychloride -- Colouring Agent Occasionally used in cheap blue compositions. Cryolite, Na3AlF6 -- Colouring Agent Also known as Greenland spar, this is an insoluble sodium salt. Sodium salts are used to produce yellow colours, but as sodium salts generally absorb water this tends to be a problem. By using cryolite this problem is surmounted. Dextrin -- Binder Dextrin is a type of starch that is added to many firework mixtures to hold the composition together. It is the most commonly used binder in pyrotechnics. Gallic acid (3,4,5-trihydroxybenzoic acid) This is used in some formulas for whistling fireworks. Whistle mixes containing gallic acid are generally the most sensitive of the whistling fireworks, with high sensitivity to both friction and impact when used with chlorates, but cannot be used with perchlorates either. There are safer alternatives for whistle compositions. Gum arabic (Gum Acacia) -- Binder An example of the various wood-resin-based adhesives used to bind firework compositions. Others used include Red Gum and Gum Copal. Gunpowder Black powder is the mainstay of pyrotechnics. At a basic level it is a mixture of potassium nitrate, charcoal and sulphur. However, simply mixing these ingredients together will not produce proper black powder. It merely produces a much milder version, which itself is used extensively in pyrotechnics, and is commonly called meal powder. True black powder takes advantage of the extreme solubility of potassium nitrate by mixing the very fine milled ingredients into a dough with water, then using strong compression to force the water out of the mixture, so that tiny crystals of potassium nitrate form in and around the particles of the other ingredients. This produces a product that is far fiercer than the simple meal powder. Hexachlorobenzene, C6Cl6 -- Colour Enhancer Used as a chlorine donor in coloured compositions that require one. Rarely used, with PVC, Saran and Parlon being preferred. Hexachloroethane, C2Cl6 -- Smoke Ingredient The basic ingredient in many military smoke formulas. Not often used with inorganic smoke mixtures, except those containing zinc. Iron, Fe -- Fuel The metal filings are used mainly in gerbs to produce sparks. Iron will not keep well in firework compositions, and so it is generally pre-coated with an oil/grease. One simple method is to add 1 gram of linseed oil to 16 grams of iron filings, mix, and boil off the excess oil. Linseed oil -- Stabilizer Used to coat metal powders in order to prevent them from oxidation, both prior to use and in the firework composition. Polyesters are used in commercial fireworks, but linseed oil remains an accessible option to the amateur. Lithium carbonate, Li2CO3 -- Colouring Agent Used to colour fires red. It has no advantage over strontium salts for the same purpose. Magnesium, Mg -- Fuel Used to produce brilliant white fires. Should be coated with linseed oil/ polyester resin if contained in a composition which is not to be used immediately, as it may react with other components of the mixture. The coarser magnesium turnings are sometimes used in fountains to produce crackling sparks. Magnesium-aluminium alloys give similar effects, and are rather more stable in compositions. Parlon -- Colour Enhancer, Binder Parlon is a chlorine donor, and a key ingredient in many coloured stars. It is a chlorinated isoprene rubber, chlorine content 66%. It interferes with burning less than PVC or saran, and can be used as a binder. It is soluble in methyl ethyl ketone (MEK) and partially in acetone. Compositions made with parlon and acetone or MEK are nearly waterproof. Phosphorus, P -- Fuel Phosphorus is rarely used in pyrotechnics today, except for a few specialized applications. It was used commonly many years ago, but as the hazards associated with its use became known it dropped out of use. Phosphorus comes in several forms, of which the red and the white/yellow varieties were used. Red phosphorus (used in the strikers on the side of matchboxes) is the more stable form, while white phosphorus (used by the military in incendiary devices) ignites spontaneously in air, and must therefore be stored under water or otherwise protected from the atmosphere. Both forms are toxic. Polyvinylchloride (PVC) -- Colour Enhancer, Binder PVC is a commonly used chlorine donor. It is not as good as Parlon for this purpose, but is cheaper and more readily available. PVC is soluble in tetrahydrofuran (THF) but almost all other solvents are useless. Methyl ethyl ketone (MEK) will plasticise PVC to some extent, however. Potassium benzoate, C6H5CO2K -- Fuel Used in whistling fireworks, in combination with potassium perchlorate. It must be very dry for this purpose, and should be less than 120 mesh. Potassium chlorate, KClO3 -- Oxidiser Originally used very commonly in pyrotechnics, potassium chlorate has gradually been phased out due to its sensitivity, in favor of potassium perchlorate. Mixtures containing potassium chlorate and ammonium salts, phosphorus or anything acidic are particularly dangerous. For this reason mixtures containing potassium chlorate and sulphur are to be avoided, as sulphur (especially the common "flowers" of sulphur) may contain residual amounts of acid that can sensitize the mixture. In general, potassium chlorate should be avoided unless absolutely necessary. Chlorates have probably caused more accidents in the industry than all other classes of oxidisers together. The reason lies in their sensitivity to acids and their low decomposition temperature. When mixed with an easily ignitable fuel, such as sugar or sulfur, chlorates will ignite from a fingernail striking a wire screen. Moreover, sulfur is often acidic, a fact that has lead to spontaneous ignition of sulfur-chlorate compositions. If you intend to use chlorates, pay extra attention to safety. Potassium nitrate, KNO3 -- Oxidiser A very common oxidising agent in pyrotechnics, potassium nitrate is one of the chemicals you should never be without. From its essential use in gunpowder to general applications in most fireworks, you will find potassium nitrate used wherever a relatively mild oxidiser is required. In fireworks it should pass 120 mesh, but can be used at 60 mesh. The fine powder should be used as soon as possible after grinding or milling as it will soon cake and have to be re-ground. Potassium perchlorate, KClO4 -- Oxidiser More expensive than potassium chlorate, but a better oxidising agent and far safer. In almost all mixtures that previously required the chlorate, safety factors have led to its replacement with potassium perchlorate. It should be used in place of the chlorate wherever possible. Potassium picrate This is a shock sensitive compound that is used in some whistle formulas. While safer than gallic acid formulas in this respect, care should be taken to keep it away from other metals such as lead, because some other metallic picrates are extremely sensitive. Saran -- Colour Enhancer, Binder Saran is another plastic chlorine donor. It is most commonly encountered in the form of the cling wrap used to protect foodstuffs. It is slightly soluble in tetrahydrofuran (THF) and will be plasticised by methyl ethyl ketone (MEK). Shellac -- Binder Shellac is an organic rosin commonly used as a binder where a water- soluble binder would be inappropriate. It can be bought at hardware stores in the form of lustrous orange flakes, which can be dissolved in boiling ethanol. Sodium salts -- Colouring Agents Sodium salts are sometimes used in place of the corresponding potassium salts, but this is uncommon due to their hygroscopic nature. They rapidly absorb water from the air, which can ruin a pyrotechnic composition. In particularly dry environments they can be used without too much trouble, and are therefore used in places like Egypt due to the relative cheapness of some of the salts with respect to the potassium ones. Sodium salts are also used as colourising agents, producing a characteristic orange flame. Strontium salts -- Colouring Agents Used to colour flames a brilliant red: Strontium carbonate, SrCO3 -- Colouring Agent, Retardant Used often for producing red colours, and as a fire retardant in gunpowder mixtures. Strontium oxalate, SrC2O4 -- Colouring Agent, Retardant, Stabilizer As for strontium carbonate, generally, but suffers from greater water content. Strontium nitrate, Sr(NO3)2 -- Colouring Agent, Oxidiser This is the most commonly used strontium salt, because it provides the most superb red colour available. Best results will be acheived if the strontium nitrate is anhydrous. Sulphur, S -- Fuel Another basic fuel in pyrotechnics, sulphur is used in many pyrotechnic formulas across the range of fireworks, most obviously in black powder. It is recommended to avoid the common "flowers" of sulphur, as they contain residual acid. If they cannot be avoided, a small amount of a neutralizer such as calcium carbonate should be added if acid is likely to present a problem. Titanium, Ti -- Fuel The coarse powder is safer than aluminium or magnesium for producing sparks, and gives rise to beautiful, long, forked blue/white sparks. Fantastic for use in any spark composition, especially gerbs. Petroleum jelly (Vaseline) -- Stabilizer Very occasionally used to protect metal powders e.g. iron by coating them with a thin film of petroleum jelly. Zinc, Zn -- Fuel, Smoke Ingredient Zinc metal is used in what are known as zinc spreader stars, which produce a very nice effect that looks like a green glowing cloud. Also used in several smoke formulas, due to the thick clouds of zinc oxide that can be produced. SPECIAL CAVEATS --------------- AVOID: Mixing chlorates with: acidic ingredients sulphur or sulphides ammonium salts phosphorus pitch or asphalt gum arabic solution. Mixing picric acid with: lead or lead compounds almost any other metal. Mixing ammonium nitrate with metals especially copper. Mixing nitrates with aluminium WITHOUT boric acid. Further Information ------------------- Further information about these chemicals, for example chemical, physical and toxicity data, can be obtained from the following books: The Merck Index The CRC Handbook of Physics and Chemistry Ullmann's Encyclopaedia of Industrial Chemistry Kirk-Othmer's Encyclopaedia of Chemical Technology The information may be found elsewhere, but these are the most comprehensive and readily available. --*** Many thanks to Dave Pierson, Christian Brechbuehler, Ken Shirriff, --*** Petri Pihko, Bill Nelson, Robert Herndon, Mike Moroney, Geoffrey Davis --*** and others for their helpful comments, corrections, additions and advice. -- ______ _____________ ______________________ ______ /\####/\ / / / / /\####/\ / \##/ \ /_______ / / _ ______ / / \##/ \ /____\/____\ / / / / \ \ / / /____\/____\ \####/\####/ / /____\ \_/ / / /_______ \####/\####/ \##/ \##/ / / / / \##/ \##/ \/____\/ /_____________________/ /____________/ \/____\/ agbrooks@teaching.cs.adelaide.edu.au Downloaded From P-80 International Information Systems 304-744-2253 |