WARNING AND DISCLAIMER: If you are underage, then consult with your parents or guardians before attempting any of this. You are on your own - I'm not responsible for your actions or harm you may bring to others because of your actions. Making the items described below can result in injury or death to you or people in your vicinity. Some things mentioned here may be illegal to make in your city, county, state, or country so check the laws that apply to you before you attempt anything described here. These notes are not complete on purpose. If you are reading them and new to pyrotechnics, then you are making a mistake. Stop now - this page is not for you. Get a beginning book on fireworks (see Skylighter or American Fireworks News (very quick shipping) for a start) and read up. You can't make any of this work without more information so read up or join a club or ask someone to help you.
OK... I'm getting bored with the same 'ol format - here is a different way of looking at things. Mike Swisher - arguably one of the greatest living experts on pyro - gave me permission to publish some of his posts on this website. Thanks, Mike.
Before we get to Mike's comments, here is my way of making dragon's eggs - pictures to follow. This is also in the composition section:
bismuth trioxide 37.5%
copper(II) oxide 37.5%
magnalium 25%You can use bismuth subcarbonate instead of bismuth trioxide, 1:1 This formula has also been reported successful using lead oxide/trioxide.
Roll the dragon's eggs dough between two pieces of baggy and between two popsicle sticks. Cut in 2mm squares. I usually run a noodle cutter up and down them and then carefully run a razor blade between the hatched noodle cutter lines. You can do it any way you want, though. Just cut them small.
I bind with a 15% solution of NC (double base smokeless). Prime with green mix and a metal - I used green mix +10 silicon +5 dextrin. Note that if you are having difficulties, the first place to start fixing things is here. Make your NC solution very thick - gravy thick.Make sure that the layers of material are bound with different methods. If the egg uses NC, use a water binding for the prime. Use an NC or acetone/parlon binding for anything on top of the egg prime.
About Mike's posts
I started looking them over and decided I didn't want to spoil the discussion so I'm just leaving the posts intact. I'll add some pictures the next time I make a batch of eggs. These posts are out of context of larger threads (in most cases) - I won't add many comments because, even out of context, they are quite good and to the point.
Comments by Mike Swisher (used with permission):
Posting 1:
<OP>, the original 'dragon eggs' I examined in 1988 were made using granules bound with a phenolic resin and matrix composition bound with collodion. Collodion is a low nitrogen content NC that is soluble in a mixture of alcohol and ether. Camphor is added as a plasticizer. The reason a plasticizer is necessary is that the pharmaceutical use of collodion is as a wound sealant. Collodion USP is sold under trade names such as ''Nu-Skin'' for application to minor cuts and abrasions. It has been around for years.
My impression is that the Chinese chose it simply because the solvents would not attack the phenolic binder of the granules, so that they would remain distinct from the matrix. If the binder of the granules were soluble in the solvent of the matrix, the granules would disintegrate and blend with the matrix composition, and the effect would be spoilt.Posting 2:
I never had much problem cutting the crackle granules when using a solution of NC in pure acetone. MEK will, as noted, slow down the drying but I'm not sure this is an advantage. My technique is to weigh out perhaps 12 oz. of the dry composition, add NC solution, and work it in till the consistency of the mix was about that of pie crust - then, placing this on a sheet of paper, and using an aluminum roller, roll the ball of composition out to 1/8'' or perhaps a bit less thick - then dice the rolled out composition quickly with a long relatively straight-edged knife. I do not bother trying to break the granules apart or to dust with prime while they are damp. I set the sheet of paper and granules to dry and break them up later, sorting them by sieving. Any that do not pass 8X8 hardware cloth are broken up till they do. Any that are not retained on window screen are re-powdered and may then be damped with acetone alone, then are again rolled out and cut, etc.
It is possible to roll out and cut quite a large amount of composition in an hour simply by repeating the above process with small batches of the size indicated above. Admittedly, if one wanted to achieve greater precision - as, e.g. for cores to be used in round stars - cutting would take more time. Since I have used my crackle granules embedded in a matrix mixture for relatively large pumped comets, this has not been an issue for me.Posting 3 This postig was amid comments as to the fear of using lead oxides instead of bismuth - one poster said it wasn't as bad to use lead oxides as everyone was making it out to be. Simply use gloves and a respirator and wash your clothes afterwards. Make it outside if possible.
I will agree with you about overstatement of lead toxicity.
The principal hazard of lead poisoning appears to be to small children who often ingest gross amounts of it from chewing on old lead paint chips, recent Chinese toys, etc.
Good housekeeping and personal hygiene make sense in handling any pyrotechnic chemicals; disposable gloves, a good respirator, washing utensils and clothing used during mixing, and promptly washing yourself after working with them should be sufficient precautions for an adult. I employed hot-metal typesetters for 20 years, some of whom had been in the trade all their lives, and none ever suffered lead poisoning. A few of them had problems with ethanol toxicity but that is another matter!
I will also observe that one of the world's great problems is not lead poisoning but lead deficiency. Many individuals would benefit immensely from a dose of 240 grains, administered cranially.Posting 4: This thread dealt with whether crackle can be rolled in a star roller
There's no reason why crackle couldn't be rolled, I just haven't bothered trying to figure out how to do it.
I suspect there may be some differences in performance because the ratio between surface area and volume/mass of an angular granule is significantly greater than that of a sphere. This will certainly affect ignition and probably the rate of the reaction once ignited.Posting 5: This thread was about whether water could be used as a binder
In my experience NC helps the heating or smoulder phase of the crackle reaction. Other binders do not have this property.
It is also important that the crackle granules be bound using a solvent and binder that are not the same as the solvent and binder employed for the matrix composition in which the granules are distributed. The purpose of this is to preserve the heterogeneity of the granules. If an aqueous binder were used for both, the granules would soften and blend together with the matrix, destroying the crackle effect.
I note that the original 'dragon eggs' imported c. 1988 contained granules bound with some sort of phenolic resin and a matrix composition bound with collodion (low nitrogen content NC + camphor, dissolved in a mixture of alcohol and ether). The camphor smell gave the binder of the matrix composition away. A splash of acetone quickly dissolved the binding of the matrix, leaving granules that did not soften or dissolve in the acetone.
Thus, NC/acetone for the granules and dextrine/water for the matrix is not a necessary combination. Any two binding systems that use binders soluble in different solvents may be used, in order to preserve the heterogeneous nature of the combined granules and matrix. This, however, does not tell the whole story, as the use of NC to bind the granules yields definite benefits in their performance.In my experience NC helps the heating or smoulder phase of the crackle reaction. Other binders do not have this property.
It is also important that the crackle granules be bound using a solvent and binder that are not the same as the solvent and binder employed for the matrix composition in which the granules are distributed. The purpose of this is to preserve the heterogeneity of the granules. If an aqueous binder were used for both, the granules would soften and blend together with the matrix, destroying the crackle effect.
I note that the original 'dragon eggs' imported c. 1988 contained granules bound with some sort of phenolic resin and a matrix composition bound with collodion (low nitrogen content NC + camphor, dissolved in a mixture of alcohol and ether). The camphor smell gave the binder of the matrix composition away. A splash of acetone quickly dissolved the binding of the matrix, leaving granules that did not soften or dissolve in the acetone.
Thus, NC/acetone for the granules and dextrine/water for the matrix is not a necessary combination. Any two binding systems that use binders soluble in different solvents may be used, in order to preserve the heterogeneous nature of the combined granules and matrix. This, however, does not tell the whole story, as the use of NC to bind the granules yields definite benefits in their performance.Posting 6:
I have made hundreds of pounds of crackle comets using NC-bound crackle granules and a water-bound, nitrate-based matrix composition. I never experienced any failure of the granules to crackle on account of moisture or nitrate.
The purpose of using NC to consolidate the granules is twofold. First, NC helps the preliminary heating or smoulder phase of the crackle reaction. My experiments in 1988 showed that granules consolidated with NC in acetone performed better than those consolidated using starch and water. Second, because different binding systems are necessary to maintain the heterogeneity of the granules and the matrix when the two are mixed together. We want the granules to be distributed in the matrix to make our crackle stars in the same way gravel is distributed in cement to make concrete, ot as raisins are distributed in rice pudding. If an aqueous binder were used for both the granules and the matrix compositions, they would blend together on dampening, and the effect would be lost.
I should note that the original Chinese dragon's eggs used granules that were bound with some sort of phenolic resin that was insoluble in alcohol, acetone, or water. The matrix composition was bound with collodion (a solution of low-nitrogen NC in alcohol and ether, to which camphor is added as a plasticizer). The use of collodion was given away by the camphor aroma of the consolidated mass. What is signoificant is that any two binding systems may be used for granules and matrix respectively, so long as the solvent used for the binder of the latter does not dissolve the binder of the former. The important thing is to keep the granule distinct from the surrounding matrix.
I believe based on what I have read here that the people who are experiencing problems are insufficiently consolidating their granules. One wants a hard, dense granule. I dampen my composition with NC solution, mixing them to form to a stiff dough, and roll it out to a thickness of perhaps 1/10 inch. I then score this finely using a sharp knife and when it is dry, break it up and sieve it. I use what passes 8X8 hardware cloth and is retained on 20-mesh. Whatever does not pass 8X8 is broken up till it does; whatever is not retained on 20-mesh is dampened and re-consolidated as previously described. This process takes more time than granulating the dampened mass through a screen, but results in much denser granules. It also does not leave the granulating screen covered with a sticky mess.Posting 7: This thread was about degradation of dragon's eggs by leeching of the nitrates into the mix and causing the pops to stop.
I am puzzled by the reports of degradation.
I have found that crackle granules made with a solution of NC keep well, and for an indefinite time, without the necessity for waterproofing, wax coating, or other such steps. To those who are having problems - with what do you bind your granules? How do you consolidate them? how do you handle them after granulation?'Posting 8: In a response about whether magnesium could be used instead of magnalium
Magnalium is generally used, though Shimizu has published some compositions that rely on litharge and aluminum alone. I do not think magnesium alone would work.
The crackle or dragons' eggs effect is best understood as a specialized strobe composition in which the normal strobing sequence of (smoulder/flash/smoulder/flash... ) is unable to continue because the flash phase is so violent that the first flash precludes further propagation of burning. The idea is to have a sufficiently small piece of consolidated composition that the whole mass of it becomes semi-reacted in the smoulder phase before it proceeds to the flash phase. Shimizu showed that the magnesium in the magnalium is consumed during the smoulder phase, and the aluminum then yields the flash (explosive) phase.
Posting 9: A follow-on to 8The magnesium strobes work because they have a two-oxidizer system - the smoulder, or low-temperature, oxidizer is ammonium perchlorate, whereas the flash, or high-temperature, oxidizer is a sulphate (typically alkaline earth, ee.gg. barium, strontium, magnesium).
The barium nitrate/magnalium strobes work because they have a two-fuel system - the smoulder, or low-temperature, fuel is magnesium, whereas the flash, or high-temperature, fuel is aluminum. Typically the Mg and the Al are alloyed, but a mixture of powdered pure metals works. According to Stanbridge, Brock had such a composition called ''Goldern Shimmeron'' in the early 20th-c., which was displayed in the famous peace display of 1919.Posting 10: More on using only NC as a binder
The benefit of nitrocellulose is that it actively encourages the smoulder phase of the crackle reaction. It does so because it is internally oxygen-balanced and actively burns by itself.
When I first investigated this effect in 1988 I found that binders that were fuels only (e.g., dextrine, starch, gum arabic, shellac) were not nealy as helpful to the effect as was NC. Cellulose acetate would behave more like a starch, gum, or resin than like NC.