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How To Make a Cremora Fireball
Read and review these Fireworks Safety Articles before starting any fireworks
project.
PGI grandmaster Ned Gorski teaches you how to make fireballs will Cremora non-dairy creamer. Materials Needed
Ya know what's really aggravating? You put many hours of sweat and labor into producing a nice fireworks display, perhaps with some homemade aerial fireworks shells and fountains, and somewhere in the show you fire some of these simple and easy-to-make Cremora fireballs. And after the show, do you hear much praise for the meticulously constructed shells that you slaved over? No! All you hear, especially from the kids, is, "Wow, we loved those big, fiery things! Whaddaya call em? They were hot!"
40-50 Foot Tall Cremora Fireball
(Photo and fireball by Noel Emge)These fireballs are definitely crowd-pleasers. And they couldn't be easier to make and shoot. The Bluegrass Pyrotechnics Guild has made and shot literally hundreds of the 5 gallon size fireballs in the displays we have produced for the Pyrotechnics Guild International's (PGI) summer conventions over the years. One time we wanted to replicate an atomic bomb mushroom-cloud in a show that had a World War II segment. We fired 13, five-gallon fireballs which resulted in this smoke cloud after the fire went out.
70 Foot Mushroom Cloud by Bluegrass Pyrotechnic Guild In another show, we had a Wizard of Oz segment and wanted to have fireballs associated with "The Great Oz Has Spoken" soundtrack. Cremora fireballs provided just the right effect. In years past I've heard of accidents at grain silos or flour mills, where clouds of dust have been ignited by a spark resulting in a tragic explosion. A bag of flour is not a fire hazard, but mix it with air and it becomes a highly flammable mixture. It takes fuel, oxygen and a heat-source to produce a fire. A Cremora fireball is simply a device which projects a powdered fuel up into the air, where it gets mixed with the atmosphere, is ignited by the propellant, which results in a large fireball as the fuel and air burn together. At some time in years past, an enterprising soul decided to project some Cremora brand coffee-creamer powder up into the air using a black powder propellant, and the Cremora fireball was born. Even though Cremora brand creamer is next to impossible to find nowadays, and other substitutes are used, these fireball pots will forever be referred to as Cremora Pots, or just Cremoras. The simplest of Cremoras can be made with just a metal can, some black powder, a 4" piece of Visco safety fuse, a disc cut out of a paper napkin, and some flammable powder.
Construction of a Typical Cremora Pot For a large fireworks display, Cremoras made in 5 gallon plastic buckets produce an impressive fireball for everyone to see. I'll provide some details on these in a moment, but these fireballs are so large that everyone really needs to be at least 200 feet from them because of safety concerns. In smaller, backyard type displays, small Cremora pots, made in 12, 15, or 28 ounce metal cans, like what soups and vegetables come in, can produce impressive, safe fireballs. Some folks use cans as large as #10 cans, or even the size of a large coffee can. Small plastic pails and cans work well as containers, too. Whatever container you use, you want a smooth interior wall, without any lip that protrudes toward the inside at the top of it. You want the contents of the pot to be able to be smoothly propelled skywards. Warning: Safe is a relative term. As with any fireworks device that propels flame into the air and has the potential to malfunction and send pieces of the container flying, it is always best to maintain safe distances from the device when it fires. Barricade the device with concrete blocks, or bury the pot in a hole in the ground. Nothing would take all the fun out of this faster than having someone get hurt, especially some innocent spectator. For these small fireballs, I start with a clean, empty can, and punch a Visco-size hole in the side of the can, right near the bottom, with a sharp awl.
Preparing Empty Can Container for Cremora Fireball Pot Note: It is best to proceed with all of the following procedures with the container in place in the location where the fireball will be shot. We want the flammable powder to stay fluffy, and this prevents the flammable powder from settling as it would if the pot was moved after assembly. If you build it in one place, then transport it to another (thereby settling and compacting the powder), instead of a fireball rolling up into the air, you are more likely to have an explosion of the can itself, possibly injuring yourself or bystanders with metal-can shrapnel. Building the device in its final location also prevents any possible static discharge between it and the ground which could occur if it was lifted up. Now, I insert the Visco safety fuse through the hole in the base of the can, put the can on the ground, and pour the black powder (BP) lifting charge into the can. I make sure the BP is spread evenly around on the bottom of the container. Then I cover the BP with a round piece of thin tissue, cut from a paper napkin or from facial tissue. This tissue barrier prevents the flammable Cremora-type powder, which is about to be added to the can, from settling in between the BP granules, which would slow the BP's burn rate. We want the BP to burn rapidly and develop enough pressure to quickly propel the flammable powder into the air.
Cremora Fireball Pot with Visco Fuse, Black Powder, and Tissue
Paper Barrier Installed Now, it's just a matter of gently pouring the Cremora-type flammable powder into the can, on top of the tissue-paper barrier, filling the can one-half to two-thirds full. If the powder you are using is clumped a bit, and is not completely free flowing, it is a good idea to sift it through a wire-mesh kitchen colander before pouring it into the can.
Completed Cremora Fireball Pot The Cremora is now ready to be fired. If it is not going to be fired immediately, cover the device with a piece of aluminum foil to prevent dew, rain, or humidity from affecting the contents. You'll want to be a good 30-50 feet away from even one of these small fireballs when it ignites. You will feel the radiant heat from the fireball as it rises into the air. If you test-fire one of these during the daytime, you might see a giant smoke ring form as well. As you are following along in this process, a few questions have probably now popped into your mind.
Commercial 2FA black powder is traditionally used as the lift powder in Cremora fireballs. A good place to start when determining how much of it to use is 0.1 ounce per square inch of container bottom. This results in the following amounts:
These amounts will result in a layer of 2FA on the bottom of the container that covers it completely and is about 1/4" thick. This is a good starting point, and can be adjusted to taste. The correct amount of lift powder will result in a great fireball, but the container will remain in place and intact. The first time I ever made 5 gallon Cremora fireballs (10" diameter bucket bottom), I used a pound of commercial 2FA lift powder in each one. "Yeah, that looks about right," I said to myself and to those around me. We ended up with great fireballs, and pieces of bucket strewn far and wide. "Hmmm, maybe we can back off on that lift powder a bit." In Skylighter Fireworks Tips, #96, we learned that it is possible to make our own, very functional, red-gum/alcohol granulated black powder using Skylighter Airfloat Charcoal, and nothing more than a couple of screens. This homemade black powder works wonderfully in these Cremora fireball pots. I actually like the slightly softer lift that this homemade BP provides. When using it, I like to use between 1.25 and 1.5 times as much as I would of the commercial 2FA amounts listed in the above table. When this subject is brought up, quite a few variables are encountered. There are many different varieties of non-dairy coffee creamer available. As I said above, I was unable to locate the actual Cremora brand. I tested Coffee Mate, Kroger brand creamer, and the cheaper store brands from Wal-Mart and Biggs. A friend of mine was able to purchase a couple of pallets of out-of-date Vitamite non-dairy powdered milk replacer, and we've been making very nice fireballs with it for a couple of years. Vitamite is available from Diehl Food Ingredients, www.diehlinc.com, but it costs $180 for a 50 pound bag.
Powdered Milk Products to use as Flammable Powder in Cremoras One member, who has attended the PGI conventions in years past, has brought 50 lb. bags of floor-sweepings from a factory that makes powdered bases for gravy mixes and soups, and has made this powder available to attendees. This powder quite often has a fat-content of 50-60%, and has produced some of the brightest and hottest fireballs I've personally ever seen. Very impressive! I have often used Land-O-Lakes Lamb-Milk-Replacer, and have been very pleased with the results. This product is now up to about $50 for a 25 lb. bag, and is often available at farm-feed supply stores. Another pyro has used a product called Glufil which is powdered walnut shells. This dust is considerably less expensive, at $22 for a 50 lb bag, and is available at www.rogergeorge.com. I've seen photos of fireballs made with it and they looked very nice. The fellow who has used it reported that it did not perform quite as well as Cremora, though. I've heard of folks using fine sawdust, or even wheat flour. One well-respected pyro recently told me that he uses finely powdered Gilsonite, which is an asphalt-like product that is available from Skylighter. I had to mill the Gilsonite that I had on hand to a fine dust in my coffee grinder, because it was originally in the form of larger crystals. Just remember that whatever you use, it must be a very fine, flammable powder. Well, all of the above information and options certainly calls for some experimenting, doesn't it? So, I got my lovely assistants, my wife and granddaughter, outside on a nice spring evening after dark, and I made up some small Cremora fireball pots in a 28 oz. can, using many of the flammable powders listed above. At the last moment, I decided to include pots made with Skylighter airfloat charcoal, powdered confectioner's sugar, and my homemade spruce/pine airfloat charcoal. Then I fired them one at a time, and we graded each one based on how impressive the fireballs were. The results were as follows, with the resulting fireballs rated on a scale of 1-5, with 1 being not-so-good, and 5 being "man-that-curled-the-hairs-on-my-arms":
Note: The one thing that kept the Vitamite from receiving a 5 was that it produced a lower fireball. It is a very fine, dense, powder, and tends to be more difficult to blow up into the air and disperse into a large cloud. I came to the conclusion that it needs to be fluffed up a bit, and decided to mix it half-and-half with sawdust in future testing. The performance of any relatively dense powder may be improved by mixing it with some sawdust in order to fluff it up a bit. These were small, backyard-type fireballs, and I wanted to see how the top performing powders compared in large, display-size Cremoras. So I took some 5 gallon buckets to a recent club shoot, and tested large fireballs there. The results were as follows:
These large Cremora fireballs from a distance of 200 feet looked better when they were brighter, and the latter two produced those kinds of fireballs. But, none of the above was bad, and each one produced its own unique effect. Warning: This can be done easily, but must be done in a particular way in order to be done safely. I have heard of someone being gravely injured when they made a Cremora, with an electric match in the lift powder and the wire leads dangling out of the bucket, and then they lifted the assembly causing a static discharge through the ematch leads and firing the bucket. First of all, the Cremora pot must be made in place and not moved. Barricade the pot by building it in a hole in the ground, or by placing safe barricades around the bucket. If you are using a 5 gallon bucket, remove the metal handle to prevent it from becoming flying shrapnel in case the bucket is fragmented during firing of the Cremora. Secondly, quickmatch, or plastic-tape-wrapped Fast-Fuse, must be run into the lift powder from outside the bucket, either through a hole near the bottom, or from the bucket top, down the inside of the bucket and into the black powder. The electric match is then installed into the end of the quickmatch/Fast-Fuse, which insulates the ematch from any static charge that might build up in the Cremora powder. Then, the Cremora pot is constructed as described above.
Constructing a 5-Gallon Cremora Pot to be Fired Electrically Note: Some folks insert an inexpensive metal mixing bowl into the bottom of the bucket, and then install the Cremora fireball ingredients in and above that bowl. I have never done this, but, reportedly, it can increase and improve the upward thrust of the powder and the resulting fireball. Interestingly, the Cremora fireball pot shown in the picture above, made at the last moment for illustration purposes, was made with the remaining 6 containers of the cheap Kroger coffee creamer that I had purchased for this project. In the small-can test shots, this powder produced only a 2.5-rated, somewhat disappointing fireball. But, the 5-gallon pot's fireball was very hot and impressive. This suggests there is plenty of room for experimentation and personal taste as these devices are developed and refined. This is what we call additional effects that ride on top of a main device or effect. I, personally, like Cremoras made simply as described above. But, sometimes powdered metals like titanium or aluminum are sprinkled into or on top of the flammable powder as it is added to the container. I've also seen small aerial fireworks shells, or just individual fireworks stars, placed gently on top of the fireball powder, to be ignited and propelled into the air when the Cremora is fired. This provides some room for creativity on the part of the fireworker, but as usual, safety precautions must be considered, and safe setbacks must be observed. Additionally, after the firing of the Cremora, the site must be inspected for any un-ignited effects. So, there you have them--some of the simplest, and most effective, fireworks crowd-pleasers you can come up with. Stay green, have fun, and don't waste that coffee creamer by actually putting it in coffee. Ned To learn more about how to make fireballs read these: "Ghost Mines: How to Make Colored Fire and Fireballs" "How to Make a Special Effects Cremora Fireball" "How To Make A Colored Fire Flame Projector For Stage Special Effects" |
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