Backyard Pyrotechnics II by Pyronomy In this second article we will discuss several different areas of amateur pyrotechnics. It is still my intent that these descriptions are for informational purposes only. WARNING: THIS ARTICLE CONTAINS DESCRIPTIONS OF DEVICES THAT CAN BE EXPLOSIVE IN NATURE. PLEASE USE CAUTION WHEN WORKING WITH ANY OF THEM. In the construction of many devices some kind of container is needed. Most of the materials that are used may be acquired from art, hardware, and grocery stores. The main components are kraft paper in different thicknesses. I have found that 30 and 60 lb. kraft papers to be most useful. Jute twine is a relatively coarse twine made from plant fibers. It is of medium strength and it is also combustible. It is mainly used to wrap aerial rounds to help hold them together tightly. Glue is also needed to hold the containers together. I have found that plain old Elmer's Glue-All is very effective. It will also burn when dry, which is a plus. Several different sized cylinders will also be needed as forms to roll up your containers on. I found brass tubing at the hobby shop that starts at 1/16" graduated at 1/32" up to about 5/8" that works great for rolling cracker cases and roman fuse cases. Common plastic pipe used for plumbing also works well for forms as it generally has a smooth surface, is real strong, and is readily available. Another useful item is the type of paper used for things such as cereal boxes, the backs of legal pads, etc. I'm not sure exactly what type of paper they are but it is great for the first layer on aerial shells. This paper is pretty strong when made into a cylinder. You will need a brush of some type to spread the glue around in thin even coats and also to work the glue into the paper if the need arises. I have found that the good old eraser with a brush on it works great for this. You will also need something to put the glue on while you work as it is too much of a pain to continually pick up the glue bottle. You tend to waste a little glue this way by it drying but is well worth the loss. AUTHORS NOTE: Due to some feedback from the first article of this series it has become evident that some individuals obviously can't read worth a damn. It was suggested that this series is just another anarchy manual. I in no way promote nor support anarchy. This series is for intelligent, resourceful, hands on type people. If you don't have what it takes to use or appreciate this information in the light given, SO WHAT. Who cares what you think as you obviously looked at the title and didn't even read the text. Oh! BY the way, I hear that your BAND reallly SUCKS. You know who you are. CASE ROLLING In the first article homemade cases were mentioned. We will now go thru step by step the procedure of this rather laborious task. The best paper that I have found for most cases is that old standby Kraft Paper. (1) Determine the size of the case that is needed. You will need to consider its length, inside diameter, outside diameter, the difference between them being the wall thickness, and most important of all the cases use. For devices that are subject to great internal pressure like rockets, roman fuses, fountains, etc.; a case that is extremely strong is needed. It should be glued all the way when rolling and must have a good thick wall. They should be allowed to dry slowly but thoroughly before use. For devices such as crackers there are a couple of different styles of cases that may be used. The first is similar to the above mentioned but be aware that these can be hazardous when fired as they throw very hard pieces of paper. The second is rolled dry until the last turn. This allows the case to disintegrate better leaving only the end plugs to worry about. The safest one is #2 but the most effective is #1. You decide for yourself what your needs are. (2) Cutting the kraft paper is the next thing. The direction of the grain of the paper is important for case strength. The grain usually runs with the roll. Roll the paper out on a flat surface the roll being away from you and the paper coming off the roll towards you. How much you pull off depends on the diameter of the case to be rolled. I have found that 18" is a good place to start as it is an easy length to work with. Square up the edge closest to you with a sharp blade preferably a razor knife. Measure 18" from this edge up towards the roll on each side. Make a pencil line between these marks and cut. Move the roll and leave the piece you just cut in the same place on board. Now determine the length of your case. Measure this distance in from either side on top and bottom. Cut from top to bottom along this line. You should now have a piece of paper whose width is the same as the length of the case you are making by 18" long. Repeat this last procedure to obtain as many pieces of paper that will be required. (3) On a good flat smooth surface align a piece of paper the length being from top to bottom. Place a cylinder of the needed diameter across the paper its length aligned from side to side so that it may roll from top to bottom of the surface. Now roll the tube with the paper until it just overlaps. You should now check the alignment between the paper and cylinder. Apply the glue all over the paper now if you are making a hard case or if you are making a soft one don't glue. I have found that with the glue I am using that it is best to glue it a little at a time as Elmer's tends to dry fast when spread thin. An alternate method that I have discovered is that if you place a piece of thin wood on top of half of the paper and folding the paper over the bottom end of the board you can put tension on the paper. This serves to make the case much stronger. By the way the first turn was left dry to help ease removal of the case from the form when rolling is complete and allows drying while on the form. This has the effect of making the inside surface very smooth. Now that you have finished rolling the paper on the form (on the soft cases glue only the last turn), hold the case and rotate the form the direction of the paper. This helps to remove the case as well as making the inside surface smooth. This also is to make sure the case does not stick to the form. Before removing the case if the ends need trimming you can use a carpet knife blade. Do this by rolling the form between the blade and the surface. Do this carefully as the blades are very sharp. It is best done while the glue is still wet. Let dry slowly for at least 2 days in a dry place. You now have a case that can withstand the rigors for whatever task it was designed for. ROMAN FUSES In the American Pyrotechnist the fuses for aerial shells were called commercial fuse. Well seeing as how this is a hobby and not a professional endeavor I don't have access to this type of stuff. So therefore I have been working with Roman Fuse to provide the required timing and ignition that is absolutely necessary for the consistent and safe deployment of these devices. This type of fuse is basically a thick walled case with 5/16" to 3/8" inside diameter and a 5/8" outside diameter and 2-3" long. They generally contain a modified Black powder mixture. This procedure is described in several of the sources that were previously mentioned. We will start by rolling the case as before. (See preceding subject) You will need several items other than the case. A ram is needed to compact the powder into the case. I have been using a piece of solid copper cylinder of a diameter that fits tightly in the case. A thick piece of wood is used as a base. What ever you use as a base needs to be hard, as you will be beating on it. I used a piece of pressure treated 2" by 6". To make the area you will be hitting hard, bore a 3/4" deep hole in the wood the diameter of the case you are using and beat toilet paper in the hole so that it is 1/2" deep. This helps flatten the bottom of the hole and helps to hold the case upright for ramming. You will need a measuring scoop to keep the powder in consistent amounts while loading into the case. One can be made by using a piece of plastic drinking straw cut at a 45 degree angle and long enough so that it can be handled easily. Once the 45 cut has been made make a wadding out of TP and another short piece of straw by packing it in the straw and ramming with something that just fits the straw. Lightly apply glue and insert into 45 cut end until it is flush with the place where the 45 and uncut sections of the straw meet. Let dry completely. By the way the size for the scoop should be 1/10th of the total amount that you need to completely fill the case you are using, filled meaning after ramming. There is no easy way of getting the size right so just experiment. The powder that we will be using is a mixture of finely ground Black Powder, Potassium Nitrate, and Sulfur. There are a couple of different formulas that are generally described in the before mentioned sources. #1) Black Powder 4 parts, Potassium Nitrate 2 parts, and Sulfur 1 part. #2) Black Powder 3 parts, Potassium Nitrate 2 parts, and Sulfur 1 part. #2 is slower than #1 and is harder to light. #1 on the other hand is almost too fast to use. These formulas are usually just mixed together real well. I have found that if you carefully grind #2 with a porcelain mortar and pestle it works just about right. It lights easily but burns slow enough that you don't have a fuse that is 4" long. Stand the case up in the hole in the board. Take a wadded up 1/4 sheet of TP and put into case. Ram this as hard as you can by hitting the ram very hard with a hammer. Remove the case and invert so that the wadding end is up. Coat the wadding with an extremely light layer of glue and allow to dry completely. Re-insert case in board. Now load in to the case your first measure of powder. It must be rammed with the ram and hammer. I use a plain old framing hammer. It should be rammed with 10 medium to hard blows from the hammer. How hard is hard? Well this is where it gets back to trial and error. I have found that after the second blow the ram should not move significantly. Try to make all of the blows as close in strength as possible. Continue this process until the case is full. Now comes the test of bravery. Ram the hell out of the case 5 times with twice as much force as you have been using. This procedure can in theory ignite the fuse accidentally. However I have not had it happen to me yet. This fuse if ignited with Black Match will light every time and will burn from 4-6 seconds depending on the formula used and ramming strength. For use in aerial shells it is always best to cross match the fuse for sure ignition and transfer of fire to the round. To do this you must drill a hole in the case in two places. The first will be inside the shell and ignites the charge included there in. The second is drilled after the fuse is installed in the shell. Into these holes are inserted the best black match that you can make. The distance between the crossmatches must be found by trial. They should be placed so that the time between them are from 3-5 seconds. Then using Black Powder in a paste form you coat the spot where the black match goes through the case. When you make the paste make sure to use only enough water to make it like a putty. It shouldn't be too wet. As an alternative you can use a 50/50 mix of water and denatured alcohol. The alcohol should be the kind that has been denatured with methanol only. I have only used this type and it has been safe to use so far. Any other denaturants might cause problems with the burning rate by chemical means or by attracting water from the air which we don't want. Anyway this is the basic description of how to construct a Roman Fuse. As with all of the pyrotechnical devices there is always room for experimentation to improve the quality of your creations. Don't be scared to try out different alternatives but be careful. Please remember to use your safety equipment any time your are constructing devices or when mixing compositions. Avoid any clothing that may create static electricity and be aware of static discharge. This can accidentally ignite compositions especially Black Powder so be wary. Timed Fuses Another method that I have found to consistently bring fire to an aerial shell is by the use of cannon fuse. It is easily purchased at most gun stores and is usually of a consistent burn rate this being approximately 30 seconds per foot which is about 2 1/2 seconds per inch. You will need 2 1/2" cannon fuse, a strip of 60 lb. kraft paper 1" wide and 18" long, and some glue. Lay paper on flat surface. Lay piece of fuse across the strip and roll up gluing the whole way. Allow to dry for two days. It may be attached by gluing into hole in end plug of an aerial round. Made in this manner the paper will assure at least 2 1/2 seconds burn time if the uncovered section of fuse is cut at a 45 degree angle where it meets the paper wrapping. NOTE: Be very conservative with the amount of glue used to prevent the fuse from retaining too much water. Chemical Safety In the first installment several chemicals were mentioned. Of these several are exceptionally hazardous in some way or other. I just read in Davis's Chemistry of Powder and Explosives something that needs to be expressed. Never mix Potassium Chlorate with Ammonium Perchlorate or Ammonium Nitrate as you can possibly create Ammonium Chlorate which is extremely powerful and very unstable. As always be extremely careful when messing with the Potassium Chlorate. I personally have not used it but have just acquired some for testing and will include any findings in a future article. In the first article I mentioned that I had just acquired some Ammonium Perchlorate. Well I've been testing some compositions including it and here are some results.(1) Ammonium Perchlorate 7 parts, Powdered Aluminum 3 parts. Not as fast as Flash Powder but really powerful when confined in a real strong container. I have had some mixed for a month and it has not degraded in any way so it appears to be relatively stable. (2) Ammonium Perchlorate 7 parts, Zinc Dust 3 parts. This is less stable than (1) as the Zinc is more volatile than the Aluminum. It burns rather rapidly with a bluish white flame leaving a white residue. When confined it has been reported by a correspondent that it is quite powerful. I have been continually experimenting with color star compositions and will include some hints along this line later on. When experimenting make sure that you only work with small amounts. This meaning a part should be in the 1/4 to 1/2 gram region. Any more than this could be too large leading to safety issues or be wasteful of expensive chemicals if you make a composition wrong. Remember this is a hobby and not a commercial endeavor. NOTE: Ammonium Perchlorate when contaminated with reducers is a sensitive high explosive and it is therefore NOT recommended for use as it can possibly detonate. I would also like to discuss alternate Flash Powder formulas in a little more detail. I have tested a composition that is made from Potassium Permanganate 3 parts, and Powdered Aluminum 2 parts. This is a nasty one. It gives an audible boom when fired in a pile 1/2" in diameter. I have also tried the Potassium Perchlorate 7 parts, Powdered Aluminum 5 parts. Faster than the Flash Powder mentioned in the first article of this series. Remember this article is mainly being written and edited on a continuing basis as I myself learn new and interesting things. So therefore I will be skipping around on different subjects throughout this series to inform you of better compositions found and also to inject safety hints when noted. I once saw a very large salute tested that measured 1" in diameter and 5" long filled 1/3 of the way with the 2-1 Flash Powder. To put it simply BABOOM. Very nice concussion and lots of white smoke. Be aware that the very explosive devices can be exceptionally dangerous when used in an unsafe manner so please be cautious when messing with them. Once again I must remind you to check those local laws to keep yourself out of trouble. I don't see any harm in what I'm doing as I do not disturb other peoples peace and quiet nor do I use my devices in any way that destroys property. Also I do not provide devices to anyone. I feel that if you are a responsible and careful person that you should be allowed to do most anything that does not harm others. It seems kind of strange that fireworks are not legal in most locales but you can buy enough guns to take over a small country. I guess you have to make the decision for yourself as to whether you want to take the risk. One rule that I have found to be of paramount importance is not to tell anyone that you don't know and trust a bunch. I don't have a problem with putting this down in text as I believe in my first amendment rights and have taken a pen name for some insulation just in case my articles scare the hell out of someone. You will not find my handle anywhere other than in these articles. I have been seeing a lot of press on the television lately about people sending letter bombs to folks. I consider this to be psychotic and its also pretty chicken shit. If you have a problem with someone put it down on paper or something. Call them on the phone or go see them. Tell them how you feel. Blowing people and landmarks up doesn't change them or their attitude. All it does is cause a lot of pain and anguish. Okay enough of the editorializing. Back to the meat and potatoes. FURNACE/FORGE I finally built one of the furnace/forges that is described in PMJB. It works so good that I figured some of you might be interested in a description of how one might build such a useful device. It basically consists of two galvanized buckets, some steel pipe with elbows and fittings, some sand, and a slightly modified elcheapo hair drier. The buckets should be different in size so that when one is placed inside the other and held 2" off the bottom there is approximately 2" of space between them. The pipe should be 1' long and 1 1/2" in diameter. You should also purchase an elbow that fits the pipe along with an adapter that will reduce the elbow down to 3/4" - 1". Cut a hole in the side of the larger of the two buckets that will tightly fit the pipe. It should be located approximately 1/2" above the bottom. Thread the pipe into the hole and into the elbow locating the elbow in the middle of the bucket. Place the smaller bucket in the larger bucket allowing it to rest on the elbow. Now cut a hole in the bottom aligned with the elbow. It should be sized so that the threads of the reducer just barely fit. Now place the small bucket back into the larger, align the hole with the elbow and screw in the reducer until tight. Now while holding the inner bucket centered pour sand between the buckets until the space is completely filled. This concludes the construction of the basic furnace. Next you will need to modify the hair drier. Most of these contain a dc motor which will run on as little as six volts. This makes them very easy to modify. Start by removing all of the screws making sure to save them for later. Remove the heating coil by cutting the wires as close to the brass eyelets as possible. Cut the power cord as close to the switch as possible. Remove all other wires and the diode from the switch. Now clean all the terminals on the switch with a soldering iron. Make sure to leave the wires attached to the motor. The modifications that I made to mine also includes a method for controlling the motors speed. It consists of two 12 position rotary switches and a string of diodes. The circuit allows for a relatively wide range of speed which is essential to accurately controlled temperature. I have included the schematic for the drier modifications. For more convenient use I have also been using an AC transformer that supplies approximately 25 volts and 1 amp of current. This is adequate for most drier motors. NOTE: The motor is generally a dc motor with a bridge rectifier soldered right to the terminals. So therefore when the speed control is bypassed the motor will be getting raw AC straight from the transformer. This has the effect of greatly increasing the speed of the motor. Using the contacts on the stock switch allows you to do this without adding another switch. Make all the needed modifications then re- assemble the drier remembering to exclude the heating coil as it is not of any use here. The cheaper full sized dryers can usually be found conveniently for about ten bucks. (I used Vidal Sassoon Pro 1500) The good thing about this setup is that it can be used with a car battery for a very long time. Don't discard the heating coil as it can be used for several purposes that I will let you know about in another article. The furnace produces lots of fumes when in use especially when using charcoal briquettes. I use Kingsford because I use it in the grill as it is long burning and gives a hell of a lot of heat. I am also in the process of getting some coal as this will probably work real well with the forge modification that is going to be our next discussion. :DO NOT USE INDOORS: The basic setup for use as a furnace is relatively simple and takes just a few minutes to accomplish. You will need a surface that is completely non- combustible. I use 2 4"X 8"X 16" concrete blocks placed on a level surface. Now using duct tape attach the drier to the pipe going around twice. Place a layer of charcoal on the bottom of the inner bucket including 1 piece on the air hole. Light them with a propane torch making sure that they are all evenly lit. Add more charcoal so that it is 4' deep. From now on the drier will be referred to as a fan as that is all it is now and because it takes me less time to type it. Turn the fan on the lowest speed and cover the inner bucket with 8 overlapping sheets of aluminum foil. If you got all the charcoal evenly lit it should take about 15 minutes to get hot enough to use. If you use a higher speed on the fan sometimes it can blow the charcoal out and sometimes it tends to burn unevenly. After it has heated up remove the aluminum foil and turn up the fan. I think you will be pleasantly suprised with the amount of heat it will produce. I have also used the furnace as a type of kiln which can be used for numerous purposes. I used it to make Copper Sulphide which is used in making a blue flame. The modification though greatly increasing the use of the furnace is the simplest thing to perform. You will need a standard small coffee can. Using tin snips make the can half as tall as normal. Lay the can on its side the bottom end away from you so that you can see inside the can. Cut slits toward the bottom that go halfway toward the bottom. They should be spaced 3/4" of an inch apart all the way around. Now bend these 90 degrees so that a flange is formed. On the side of the can that is still intact drill three staggered rows of 1/4" holes around it spaced 3/4" apart. To use this modification place it bottom side up over the air hole in bottom of furnace before loading the charcoal. This directs the air out to the sides instead of straight up allowing better air flow to the fuel and also gives you a place to set things such as assay crucibles, etc. To better contain the heat use aluminum foil sealed all the way around the inner bucket leaving a 1" slit to monitor conditions inside the furnace. To use the furnace as a forge you need to go to the hardware store and acquire some heating duct reducers. One that is 7" to 6", the other 5" to 4". Place the larger of the two in the stock furnace with the larger side down. Carefully one handful at a time place sand inside the reducer on the bottom until it is level with the airhole. Now insert the smaller reducer inside the larger with the larger side down. Embed it into the sand until it is touching bottom. Carefully fill the space between the reducers with sand until full. Alternately you may also fill in between the larger reducer and the inner bucket to get more insulation but remember it will retain heat a long time. Get a bathtub drain strainer made from chrome plated steel and place over the airhole. Be aware that this modification is only for use once or twice as the amount of heat produced will burn holes in the duct reducers after only a couple of uses. I am in the process of getting some steel pipe for this purpose and will let you know the results later. To use place enough charcoal in the bottom to cover it. Light it with propane torch. Fill the rest of the way with charcoal then lay four sheets of aluminum foil that has been folded to 8" in diameter on top of the forge insert. Turn fan onto a relatively high speed and wait. It usually will be hot enough to melt steel in about 10 - 15 minutes. You may also use a steel ladle to melt aluminum. This may be made from one of the cheap grocery store ladles by drilling out the rivets and installing a handle made from #4 copper wire. It can be flattened in a vise or by beating with a hammer on a hard surface. When melting aluminum try to keep the ladle glowing a bright red or the aluminum won't melt completely. The Copper Sulfide mentioned previously was made by the method described in Pyrotechny by Weingart. Set up the furnace with the kiln adapter. Light it and allow to come up to temperature. Place a crucible that has been packed with Sulfur and pieces of Copper sheet cut 3/4" square. Fill them to within 1" of top of crucible. Cover crucible tightly with suitable top. I made one from a red clay dish that is sold at the hardware store. NOTE Make sure to bake the assay crucible at 300 degrees for a couple hours before loading it with your chemicals to make sure that it is good and dry to prevent cracking when placed in the high heat of the kiln. Cover the furnace leaving the slit for observation. Adjust the fan speed so that the fire maintains a bright red glow. After about 10 minutes the crucible will be hot enough for the Sulfur to start fuming. Stay upwind as the fumes are extremely nasty and harmful to eyes, nose, and lungs. After these start you will need to keep the temperature at a red heat for one hour. After this has passed turn off the fan, remove it and seal up the pipe with a piece of aluminum foil. Also cover the furnace securely with several sheets of foil. Wait another hour for the crucible and fire to cool somewhat. While wearing thick welding gloves remove the crucible and set on cinder block for another hour. When you open it up you will find a dark mass that sometimes includes pieces that retained the shape of the Copper squares. You should not find any Copper residue in the form of Copper in the mass. Grind small amounts of the mass in a mortar and pestle and store in an airtight container. Uses for this chemical will be discussed in more detail in a later article. This concludes this installment of the series and as always PLEASE BE CAREFUL.