Ignitor Pyrogen

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So I have Watco lacquer and a ton of Estes starters. Should I remove the starch first??? I don't need these for regular launches, but for the pics below I think I need the increased reliability. Alternate is to use FirstFire micros but that is costliness... I think the "7" cluster can work with Estes. The "12" will need longer starters. The USR Warp 7 (left) - I used glue prime/glue rivets/paper hinges due to weight and fin span. Thought about TTW but instead built as spec'd. Cheers / Robert
The white stuff is simply cornstarch and a water-based glue, similar to Elmer's (cheapest available you can bet). It'll come off with water. Almost immediately with hot water. Leaving it on will probably work with dipped wires, but it'll still slow initial fire-up, and that junk just takes up a little space where true pyrogen could be. Dry wires thoroughly before dipping into slurry. Take care not to disturb wire too much during handling. Simples.
 
I tried hitting pills with a hammer and burning them with no dice. Like posted, there are so many excipients in NTG pills for symptomatic relief of angina pectoris I doubt they would be a useful source for motor starters. Yes, I slipped one under the tongue one time and had a mild headache for a short time and fast heartbeat. Made sure I was well hydrated first so I wouldn't pass out. Wanted to see what patients experienced when they took the stuff for chest pain. No big deal and once was enough for me.

I found it easier to get the components for some of the posted formulas for igniters out there. The BP use looks intriguing to me.

Kurt

Yup, extracting from meds not really a realistic approach and pure NG requires special handling. And doesn't, by itself, have any utility in starter enhancement for rocketry. Regarding the cautions about using double-base smokeless for making NC lacquer, they are largely overblown. I and many others have stored double-base bound comps and igniters for well over a year without issue. This includes professional pyrotechnicians who literally used tons of Dot double-base over the years. I've also stored double-base NC lacquer for over a year with zero separation--there's plenty of stabilizers in there. Once hardened on a starter you're not going to see any NG "weepage" like they used to have in older, non-stabilized dynamite formulations. And unless you're licking your fingers while you work, you're unlikely to get any "dynamite headache". I never have and don't personally know anybody else that has. Gloves are cheap. So is fresh air.

The specific dangers of NG in double-base NC lacquer: NC lacquer is typically 10% w/w double-base solids (w/v for the lazy, which means it's slightly more concentrated in acetone). This is 100mg/mL = 100mg/1000uL (microliters). A typical eyedropper dropsize is approx 25uL (about 40 drops/mL). I'm probably using a 25-microliter drop of pyrogen slurry for a single-dip igniter. My pyrogen slurry is approximately half NC lacquer/half pyrogen, so really only 12.5uL/starter is NC lacquer. That 25 uL of NC lacquer contains 12.5 mg of double-base solids. For comparison, a .22 long rifle cartridge is typically loaded with 1 grain (65mg) of smokeless--5x more than I'm using in a starter, which will never experience firearm chamber pressures, ever. The NG content in double-base is usually somewhere between 10-35% of the comp, so let's go middle ground and suppose it contains 25% NG. So, of the 12.5 mg of smokeless solids/igniter, 25%, or just over 3 mg, is NG. For comparison, extended-release NG tablets contain up to 6 mg NG. Point being that the estimated 3 mg NG we're talking about per starter is essentially a trivial quantity. So much so that I would happily demonstrate its deflagration when a miniscule 3 mg of pure NG is hit with a hammer, wearing basic eye protection and nothing more. A 3 mg sample of NC (probably closer to 2 uL because, ya know, specific gravity) would fit inside the letter "o" as read here; probably on a pinhead. It's not plutonium. And the modern plasticizers and stabilizers are very effective at preventing degradation during storage, particularly when "dry" and stored in the dark.

All said, though I agree with Kelly above that using single-base smokeless is theoretically best, and I recommend it, I have absolutely zero real-world experiences that suggest that double-base is anything but safe for making NC lacquers for use in both pyrotechnic comps and as a flammable binder/slurry for enhancing starters. Unless a valid reference is provided, I maintain that any rumor of NG "separation" from double-base NC lacquers remains anecdotal, at best. BTW, any IMR powder that ends in 4 numbers is single-base, NC-only, smokeless.
 
Besides not being a good source of NC, the lacquer products have many VOC's that we shouldn't get exposed to. They will certainly coat your igniter to protect it, but not energetic to use as a primer or binder.
Actually, they probably will work reasonably well. I've only ever used them for fireworking Dragon Eggs (once, in a pinch) and as a slurry for a BP-enhanced starters, both to good effect. I was surprised the extraneous materials in the Mohawk brand didn't impact comp-super sensitive DEs, but predicted, and obtained, decent results as a flammable carrier/binder for starters. I would take exceptional care with your chemistry, however, if you are using any kind of organics in pyrogen comps, though I cannot envision why somebody would find this necessary for rocket motor starters. It's not. And I'd be particularly aware of any potential interactions between pyrogen oxidizers and all of the solvents in these mixes. You're really just looking for a flammable binder that sufficiently ignites a hot/sparky pyrogen mix. It's the pyrogen that does the heavy lifting. Anybody that's ever lit a pile of smokeless can tell you that unconfined it burns: 1) slower than BP, and 2) not exceedingly hot. That said, the plasticizers, plastics, and pigments in paint or non-NC polymer-based slurries tend to burn dirty and might inhibit your pyrogen, resulting in sub-optimal fire-transfer characteristics. I'd consider these low-nitration, low-NC lacquers for a back-up, but they'd certainly never be a first choice. This becomes important to fellow rocketeers (and fireworkers) in the many nations (much of Europe, India, Australia to name just a few...) who do not have access to other purer NC sources or to smokeless powder. And the VOCs should be of minimal concern if you're practicing safe chemistry and not snorting the stuff. And once dry...voila! No VOCs... A valid but easily mitigated concern. Else guitar makers and model airplane enthusiasts would be dropping like flies.
 
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Besides not being a good source of NC, the lacquer products have many VOC's that we shouldn't get exposed to. They will certainly coat your igniter to protect it, but not energetic to use as a primer or binder.

After the many solvents in NC lacquers evaporate, what you have left is a layer of cellulose. No different than any NC product, ping pong balls or whatever.
You can get it very cheap almost anywhere. I never understood making it from pingpong balls.
 
After the many solvents in NC lacquers evaporate, what you have left is a layer of cellulose. No different than any NC product, ping pong balls or whatever.
You can get it very cheap almost anywhere. I never understood making it from pingpong balls.
When the NC lacquer dries, there is more acetate left than NC. When single-base powder (in acetone) dries, it is almost all NC.
Both the lacquer and the powder are about the same price, but there's 10x more NC in the powder. And you know what is in the air... just mild acetone, and not a mix of dangerous VOC's.
 
After the many solvents in NC lacquers evaporate, what you have left is a layer of cellulose. No different than any NC product, ping pong balls or whatever.
You can get it very cheap almost anywhere. I never understood making it from pingpong balls.
Sorry amigo, but that is incorrect. Cellulose and nitrocellulose are entirely different chemicals. And the pyrogenic quality of nitrocellulose is dependent on it's nitration extent/status. Cotton is largely cellulose, with no nitration (though often contaminated with the other common plant polymer, lignin, which crosslinks cellulose molecules). Celluloid/ping pong balls are primarily cellulose dinitrate (or dinitrocellulose). The high-nitration, high flammability (and explosive) component in smokeless powder/guncotton is cellulose trinitrate (or trinitrocellulose). You can also have a mixture of these, even on the same long polymeric cellulose molecule, where some of the linked glucose residues (yes, cellulose is simply a long chain of glucose molecules) are variably nitrated along the chain. Low-quality (for flammability purposes) means lower nitration status. High-quality means more nitrate moities are attached. Max theoretical nitration is approximately 13.5% relative nitrogen mass (not nitrate ion/moity mass) in total cellulose--this is what's used in smokeless powder and used to be used as an explosive propellant in early ship artillery (Cordite, anybody?). Chopped up ping-pong balls (probably 11% nitration) burn nicely but would not have the same effect.

Here's a view of two residues from a long chain of trinitrocellulose. The little 6-sided shapes in the middle are glucose residues. The NO3 residues are nitrates. These nitrate bonds are unstable and would prefer to break, releasing a lot of energy. There are 6 carbons in glucose (also known as "blood sugar", aka dextrose; half of a sucrose table sugar molecule...). Two of these carbons are involved in linking themselves to other glucose residues on either side, in a long chain using oxygen as the linker--these are called glucosyl bonds. That leaves 4 free carbons. Three carbons can be nitrated. The 4th carbon cannot because of steric hindrance (not enough physical space to squeeze it in). So, one, two, or three carbons can be nitrated, converting cellulose to cellulose nitrate, cellulose dinitrate, or cellulose trinitrate. The more unstable nitrate bonding, the more vigorous the burn. It is also possible for a long molecule of cellulose to have variably nitrated glucose residues, which is why the %nitrogen becomes the important descriptor when discussing flammability.

Armchair chemistry becomes dangerous when it involves energetic compounds. Cellulose=nitrocellulose is a dangerously incorrect misunderstanding, and a myth that risks physical harm to others.

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When the NC lacquer dries, there is more acetate left than NC. When single-base powder (in acetone) dries, it is almost all NC.
Both the lacquer and the powder are about the same price, but there's 10x more NC in the powder. And you know what is in the air... just mild acetone, and not a mix of dangerous VOC's.
There have never been ping-pong balls made with both NC and cellulose acetate. The latter was the replacement (one of) for NC. If you use older celluloid PP balls, you get a combination of dinitrocellulose and camphor remaining after evaporation, which burns, but not as well as NC used in smokeless. The newer PP balls are crap and will burn but burn like plastic. And you'll probably be scratching your head wondering why they just won't dissolve in acetone (even cut up celluloid balls take a long time...).

And acetone is also considered a toxin by every environmental and health agency. It, by definition, is also a VOC. But that's not going to stop women from using acetone-based nail polish and remover, will it?
 
There have never been ping-pong balls made with both NC and cellulose acetate. The latter was the replacement (one of) for NC. If you use older celluloid PP balls, you get a combination of dinitrocellulose and camphor remaining after evaporation, which burns, but not as well as NC used in smokeless. The newer PP balls are crap and will burn but burn like plastic. And you'll probably be scratching your head wondering why they just won't dissolve in acetone (even cut up celluloid balls take a long time...).

And acetone is also considered a toxin by every environmental and health agency. It, by definition, is also a VOC. But that's not going to stop women from using acetone-based nail polish and remover, will it?
I wasn't talking about ping pong balls. There's really no way of knowing what is in them. I was pointing out the content of the so-called NC lacquers with dangerous, unnecessary ingredients.

Both in cost per gram of NC and the quality of the compounding, single-based powder is the best option by far. No argument there.

Acetone is the least dangerous solvent. The human body produces it and knows how to get rid of it. It also evaporates so quickly that it doesn't have time to get absorbed. Other heavier ketones, and benzenes and xylenes, are toxic, and accumulate over time in the human body.
 
I wasn't talking about ping pong balls. There's really no way of knowing what is in them. I was pointing out the content of the so-called NC lacquers with dangerous, unnecessary ingredients.

Both in cost per gram of NC and the quality of the compounding, single-based powder is the best option by far. No argument there.

Acetone is the least dangerous solvent. The human body produces it and knows how to get rid of it. It also evaporates so quickly that it doesn't have time to get absorbed. Other heavier ketones, and benzenes and xylenes, are toxic, and accumulate over time in the human body.
When the NC lacquer dries, there is more acetate left than NC. When single-base powder (in acetone) dries, it is almost all NC.
Both the lacquer and the powder are about the same price, but there's 10x more NC in the powder. And you know what is in the air... just mild acetone, and not a mix of dangerous VOC's.
Well, without starting a pointless argument, none of those lacquers leave behind any "acetates" as solids. n-butyl acetate is another highly volatile solvent (pleasant smelling though) that evaporates. That was my primary counter to your possibly misworded statement of "acetate" residue.

But you are indeed correct that many of the other solvent ingredients are toxic. That's why there's an MSDS. So is the gasoline you inhale every time you fill up--it is not one chemical and it contains many volatile additives, all toxic.

My only point was that, contrary to your supposition, there are probably zero solid acetates remaining after lacquer evaporation/hardening. Knowing all ingredients on the lacquer MSDSs, that is simply not likely.

Happy to discuss chemistry and pyrotechnics and rocketry (and vegetable gardening) with any bright individual anytime in any forum, but this one is mostly rocketry restricted. Besides disagreeing with your solid "acetate" conclusion, I appreciate and agree with your insights into other potentially hazardous VOCs in some commercial lacquers. That's what fresh air is for. These commercial lacquer mixes are used by woodworkers nationwide and internationally, and the true danger is mitigated by common sense use. With basic sense, associated "dangers" are easily minimized. I prefer an open window to a VOC-adsorbing respirator, myself.
 
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I just took the original crummy Estes igniter/starter and cut up ping pong balls into tiny pieces since they are made of cellulose nitrate it burns really good and then added acetone to make a glue paste then dipped them into this glop and then dipped them into 4 F real black powder. Now I never have a misfire and the launch is instantious !
I tried to take a photo of the violent blaze that they have now in the one photo. If you can't get 4 F real black powder just buy some fire crackers and unroll them to get flash powder or fine black powder that they have in them.
Maybe not. Firecrackers (1.4g) are flash powder, which is a different beast from BP. Current commercial firecrackers do not contain BP. At least within your lifetime. And plenty of the Chicoms use plain chlorate oxidizer instead of perc (chlorate is cheaper), which absolutely does not play well with sulfur-based comps (uhhh....BP.....). Probably not an issue unless you stored motors with chlorate starters inside (uh, decided not to launch today...next week turns into next year?), but chlorates and sulfur compounds don't play well together. And the standard, and I mean standard, 70:30 flash is not what you want to use for a motor-starting pyrogen. It'll burn up too fast, too violently, and probably crack a propellant grain before igniting it. Unnecessary. BP burns at over 3000F. Add a little metal and you can easily achieve 3800+F. Enough to light any APCP fuel.

Ancillary Point: Commercial firecracker pyrogen is explosive flash powder, whether chlorate or perc based (perc's more expensive and the Chicoms are all about maximizing profit vs safety). Salutes have never been (since perhaps the 1800s) BP based, for good reason. In the US, the consumer ground effect salute is limited to 50 mg pyrotechnic, aka flash powder. Nobody uses BP in commercial solutes/firecrackers because it requires serious containment to actually deflagrate (you notice I do not use the word "detonate" because BP does not have that capacity, ever). 50 mg of BP would be a joke in a firecracker and is thus never used.

Primary Point: Don't use firecracker-derived flash powder for rocket motor igniters--let firecrackers be firecrackers, and nothing more. Dumbed down FP is a useful fireworking pyrogen, but you have to know what you're doing. IF you are disassembling commercial firecrackers/fireworks (illegal), then you for sure DO NOT know what you're doing and will never know the exact comp formulation. You're guessing. Please don't do that. We never guess with energetics.

If you use true FP as your pyrogen, you risk cracking your propellant grains before ignition and can expect a CATO nearly every time. And you might hurt yourself/others. BP is better. Add a little metal if need be for APCP. Easy.
 
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Terry,

Does the "speed" of the Smokeless Powder matter ? ( "Blue Dot" vs "IMR 4350", for example )

Is Acetone the solvent used ?

Dave F.
No. Not at all. "Speed" of powder just reflects how fast that physical structure (thin wafers vs thick extruded pellets) affects burn rate. For example, shotshell powder is typically thin wafers that burn quickly because you need to generate a lot of gas quickly to propel a bunch of projectiles down a (relatively) short barrel. A magnum rifle powder would burn slower to allow maximum pressure to build up gradually, as a projectile makes it's way down a longer (relatively) barrel. For rocketry pyrogen purposes for making "starters" it's all the same. All burn very similarly. The smokeless "speed", however, might reflect whether you have wafers/discs or pellets, which is usually a non-essential consideration and only relates to how fast you will get your powder dissolved in solvent (usually acetone). That said, I happily prefer my near-immediate dissolving double-base (NC and NG) Hodgdon's Internationaol over my single-base (NC only) IMR pellets that take forever to dissolve...

Smokeless powders from any given company generally contain similar energies when burned. Their physical, not chemical, format decides burn rate of different powders. That all goes straight out the window when smokeless is dissolved in solvent and used as a binder.
 
I have a can of Mohawk. I will test it tonight. I also have several other brands. Maybe the old can I have has a different formulation, but it worked in the past.
 
As an OT aside, I just read in the Peoria Journal Star newspaper on page A8 today, Saturday that three men in North Utica were found dead along the Illinois River just west of Starved Rock State Park.
It was said they ignited a "black powder" substance near the riverbank killing all three. Didn't say if it was commercial or homemade BP. No identities or ages reported either. Autopsies were planned (maybe on the pieces?) sic.
Unrelated to rocketry of course but talk about totally STUPID!!!
Man, I don't know what else there is to say.

Kurt Savegnago
 
As an OT aside, I just read in the Peoria Journal Star newspaper on page A8 today, Saturday that three men in North Utica were found dead along the Illinois River just west of Starved Rock State Park.
It was said they ignited a "black powder" substance near the riverbank killing all three. Didn't say if it was commercial or homemade BP. No identities or ages reported either. Autopsies were planned (maybe on the pieces?) sic.
Unrelated to rocketry of course but talk about totally STUPID!!!
Man, I don't know what else there is to say.

Kurt Savegnago
I do. Besides sorry for their families. Play stupid games & win stupid prizes. Posthumous Darwin Awardees. Insufficient background knowledge. Nonexistent safety knowledge. Another reason for CPSC to announce new rules that are "good for you".

There are many very energetic black comps besides black powder, that are easier to make than BP. Every year the CPSC puts out a summary report on fireworks/explosive injuries/deaths. The most recent is 2019, attached. An interesting read. Essentially all preventable. Only a few true "accidents".

Re Chuck and Mohawk lacquer, I recall it being a little thin and benefiting from pre-evaporating some solvent before using as a carrier for wire dips. Usually 10% NC pours like syrup. Then again, some folks might appreciate this thinness--you can get a little more pyrogen into it before it becomes too thick to work with. But this lower relative amount of binder might make starter pyrogen coatings weaker and more susceptible to physical damage.
 

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  • 2019-CPSC Fireworks Annual Report.pdf
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Well, without starting a pointless argument, none of those lacquers leave behind any "acetates" as solids. n-butyl acetate is another highly volatile solvent (pleasant smelling though) that evaporates. That was my primary counter to your possibly misworded statement of "acetate" residue.

But you are indeed correct that many of the other solvent ingredients are toxic. That's why there's an MSDS. So is the gasoline you inhale every time you fill up--it is not one chemical and it contains many volatile additives, all toxic.

My only point was that, contrary to your supposition, there are probably zero solid acetates remaining after lacquer evaporation/hardening. Knowing all ingredients on the lacquer MSDSs, that is simply not likely.

Happy to discuss chemistry and pyrotechnics and rocketry (and vegetable gardening) with any bright individual anytime in any forum, but this one is mostly rocketry restricted. Besides disagreeing with your solid "acetate" conclusion, I appreciate and agree with your insights into other potentially hazardous VOCs in some commercial lacquers. That's what fresh air is for. These commercial lacquer mixes are used by woodworkers nationwide and internationally, and the true danger is mitigated by common sense use. With basic sense, associated "dangers" are easily minimized. I prefer an open window to a VOC-adsorbing respirator, myself.
I have direct experience in formulating dielectric coatings with VOC's. The residual additives are there for a purpose and not all evaporate off. NC alone as a lacquer does not have the physical properties required for a wood finish (stretch, anti-glazing, UV protection, etc.). Typical NC-based guitar lacquers have a dried content of 2/3rds NC. (I've played guitar for 50 years and have several old acoustics). And as you pointed out earlier, the lacquers (and mystery ping pong balls) have a low-nitrated cellulose compared to single-base reload powders.

For a protective coating on an igniter, the NC lacquer is fine. But, as a primer or binder, the NC from the single-base reload powder is the real thing, far more energetic. And it's cheaper per gram of NC than any other source!

I don't agree with your personal preferences on handling toxic VOCs. Neither does OSHA and the EPA and the CPSC. You are free to pontificate all you want, but other readers here should do their own research and not follow your advice.
 
I wasn't talking about ping pong balls. There's really no way of knowing what is in them. I was pointing out the content of the so-called NC lacquers with dangerous, unnecessary ingredients.

Both in cost per gram of NC and the quality of the compounding, single-based powder is the best option by far. No argument there.

Acetone is the least dangerous solvent. The human body produces it and knows how to get rid of it. It also evaporates so quickly that it doesn't have time to get absorbed. Other heavier ketones, and benzenes and xylenes, are toxic, and accumulate over time in the human body.
You've convinced me to trade up my Deft for acetone + single base, thanks for taking the time to explain.

* REFINED PETROLEUM DISTILLATE 8052-41-3 18.02
* ISOBUTYL ISOBUTYRATE 97-85-8 10.96
* SOLVENT NAPHTHA, LIGHT ALIPHATIC 64742-89-8 9.41
* METHYL n-AMYL KETONE 110-43-0 9.14
* 2-BUTOXYETHANOL 111-76-2 8.99
* NITROCELLULOSE 9004-70-0 8.22
* 1-BUTANOL 71-36-3 4.86
* XYLENE 1330-20-7 3.95
* ISOPROPANOL ANHYDROUS 67-63-0 3.52
* 2-BUTOXY ETHYL ACETATE 112-07-2 3.05
* ETHYL BENZENE 100-41-4 1.09
 
I did some igniter testing today with Mohawk and I can confirm it works. I order another Quart to test. We will see if they are the same.
 
I have direct experience in formulating dielectric coatings with VOC's. The residual additives are there for a purpose and not all evaporate off. NC alone as a lacquer does not have the physical properties required for a wood finish (stretch, anti-glazing, UV protection, etc.). Typical NC-based guitar lacquers have a dried content of 2/3rds NC. (I've played guitar for 50 years and have several old acoustics). And as you pointed out earlier, the lacquers (and mystery ping pong balls) have a low-nitrated cellulose compared to single-base reload powders.

For a protective coating on an igniter, the NC lacquer is fine. But, as a primer or binder, the NC from the single-base reload powder is the real thing, far more energetic. And it's cheaper per gram of NC than any other source!

I don't agree with your personal preferences on handling toxic VOCs. Neither does OSHA and the EPA and the CPSC. You are free to pontificate all you want, but other readers here should do their own research and not follow your advice.
Then it would appear we are in agreement on all counts!

Excellente!
 
I did some igniter testing today with Mohawk and I can confirm it works. I order another Quart to test. We will see if they are the same.
js and dh are probably quivering in their shoes about the potential cancer and liver damage you might cause for yourself with all of those scary hard-to-pronounce solvents it contains. BE CAREFUL!!! Aww shoot, the stuff works, it's the only option for many outside the US, and any risks due to VOCs are easily mitigated. Appreciate caution, but ya just can't go through life scared of your own shadow...

Check out the MSDS for table salt sometime. It's toxic! Life is scary, whoooooo!
 
Note that there are TWO cylinder locks on the revolver, not just one like most others, powered by H110:

View attachment 463342
Oh that is just nice. Used to have an 8-3/8" S&W 626 in .44 cal that would saw fenceposts in half, but I think you've got me way outdone there. Gotta look up getting one of those gadgets--looks like a lotta fun. You actually loading with BP???
 
Oh that is just nice. Used to have an 8-3/8" S&W 626 in .44 cal that would saw fenceposts in half, but I think you've got me way outdone there. Gotta look up getting one of those gadgets--looks like a lotta fun. You actually loading with BP???

No , only my loads are done with H110
 
Firefox sells it for $18 a quart plus shipping. http://www.firefox-fx.com/ChemN-P.htm
Scroll down to the 16% NC, Standard. I use the clear.
Although Chuck has apparently had good results when recently dealing with Firefox, they earned themselves a very poor reputation in recent years--lost/inaccurate orders, mischarging, poor comms including ghosting, no order or shipping confirmation, etc. So, essentially nobody that I know in a large fireworking community will chance an encounter with them anymore. My last order with them was 1.5 years ago and was an unprofessional mess that I had to arbitrate (read: cancel payment) through my credit card company when Diane ceased comms after payment. A shame because they used to be a go-to source for pyrotechnicians nationwide. It's a family business (husband and wife Gary and Diane, and kids Skylar and what's his name) who did well for years til they got busted for selling M80 kits. Hopefully they've recovered by now but they certainly hadn't when I ordered from them a few years ago. Also, they are one of the few that CSPC & BATFE requires customers to provide a copy of photo identification, and order information is regularly forwarded with identifying info to the guv. Now you might not consider this an intrusion in your privacy, but I certainly do. Anyways, the 16% NC refers to the amount of NC dissolved, not the nitration status. I think it was around 12.5% last I checked, which is respectable, but would confirm again anyways. Pyrochemsource dot com sells 12.3% NC for $16/lb, same as Firefox, and is a much more reliable company in my experience. Please keep in mind that if you purchase pure NC, that it is likely not stabilized (usually with diphenylamine) and is subject to degradation. If you ever see orange fumes or smell acrid odors, those are nitrogen dioxides that are an indication of degradation and instability (dissolved in water, nitrogen dioxide gives nitric acid). Burn pile immediately...
 
js and dh are probably quivering in their shoes about the potential cancer and liver damage you might cause for yourself with all of those scary hard-to-pronounce solvents it contains. BE CAREFUL!!! Aww shoot, the stuff works, it's the only option for many outside the US, and any risks due to VOCs are easily mitigated. Appreciate caution, but ya just can't go through life scared of your own shadow...

Check out the MSDS for table salt sometime. It's toxic! Life is scary, whoooooo!
One chainsaw has a stripped thread that causes the blade to sometimes loosen up a bit, the other does not. Which one do you use?

One car has squeaky breaks and sometimes grinds, the other does not. Which one do you use?

One baseball bat has a small crack in the handle under the tape, the other does not. Which one do you use?

If you can't tell the difference between sweeping your workspace and being scared of dirt, don't put that on me.
 
I will add that very early on when I started I used Ping Pong ball lacquer for igniters. I used a particularly energetic, multi-component, oxidizer/metals pyrogen mixture I made from scratch.
They worked fine but I later bought some "real" NC lacquer and use that with the same pyrogen now. I wanted to be a "real" purist. :)
Probably PP ball lacquer with the BP pyrogen might not be the best way to go but anyone whose tested with it over time, feel free to correct me. As one has mentioned, the components in ping pong balls have probably changed over the years. I've read early on they were made out of true NC lacquer/plastic WITH an inhibitor added so they don't go "pop" when one hits them with a paddle. I assumed that's what I was working with 17 years ago but the pyrogen I mixed up was particularly energetic. (ie. came on light quickly, flared energetically without popping) That probably overcame any deficiencies with that early PP ball lacquer I made.
One tip (and I've mentioned this before): If one ends up with a batch of igniters that go "pop", meaning some pyrogen blows off the wire, breaks the wire and doesn't come up to heat, I suspect the oxidizer/metals ratio might be incorrect. Nonetheless, the igniter batch can be salvaged nicely with one simple trick. Take the igniter head and bend it to put one to three transverse cracks in the pyrogen depending on how long the pyrogen head is. Yeah, you might lose a little pyrogen but most of the time I can place the cracks and not lose pyrogen. Some of my pyrogen heads are probably longer than need be.
I started doing that and the igniters work great. I unfortunately ended up with a large batch of "poppers" and this trick saved them for use.
What I suspect is happening is there is uneven heating of the nichrome, gas builds up too fast leading to the igniter to "pop" and break the wire resulting in a dud. The cracks allow the uneven gas buildup to escape and the pyrogen doesn't pop off. It has time to catch and burn.
I took a "nearly drained" 12 volt battery and did some testing on the batch and it took longer for the heat flux to build up and the igniters burned nominally without cracking the pyrogen heads. There was no uneven gas buildup over the nichrome. O.K. if one wants to use a partially discharged battery and wait 2 to 3 seconds for the rocket to launch then fine. I think a few transverse "cracks" is an easier way to salvage a batch.
Oh note well: I never had this issue with commercial pyrogen kits at all. The ones I used work fine and I recommend a neophyte purchasing a kit to avoid all this rigamarole I went through. Get a wire wrap tool too. People can argue the need for silver soldering the nichrome to the copper lead wires but I got lazy and just use wire-wrapping alone with decent results. The acid flux needs to be neutralized and soldering is just an un-needed step.
O.k. If one is looking for "instant-on". That's another story that I have to admit I've never mastered. I've been told the magic word is "thermite" but can't really discuss that here because formulas would need to be mentioned which isn't appropriate here. Some of the thermites (the doctored ones) can be very dangerous. Some of the straight 2 component ones have a high heat of activation and are relatively safe. Caveat here: If a two component thermite mix is made with ultra-fine powders they can explode or conflagrate at a very high rate.
Example: I took a high heat of activation 2 component thermite mix that is not ordinarily sensitive to ignition. I mixed up 4 grams.
I placed 1.7 grams of the two component thermite in a small plastic canister that had a 12 volt igniter I use to ground test ejection charges. (No need to waste an ematch for ground testing BP ejection charges for rockets)
Took out my launch panel, stood 20 feet away and the thing went up like an M80. The components were too fine a grind, were apparently mixed well and just burned at a very fast rate and made a large "bang". Particle sizes are extremely important when working with powdered thermite.
Also, if one thinks they can have a cheap explosive here. Think again. I tried 10 more times with the same fine ground components and just observed a high speed burn with no bang. The stuff was too inconsistent to use for motor ignition as the flash didn't have a long enough duration and I presume heat flux to start an APCP motor. Those components were too finely ground to make for instant on or staging thermite ignition.
Some of the doctored thermites can go up with an ematch and need a healthy dose of respect and safety equipment.
Take my advice, if not experienced, buy a kit to make igniters for ground launch igniters. If wanting to do airstarts and staging, become an established friend of someone who does it consistently. I've never attempted either and would have to find somebody who does if I was going to try it.
Kurt
 
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