I made a dip last night with the base being an ABS slurry. It works. I have plenty of ABS from failed prints.
Probably. Typical degradation products of NC are reddish gas emission and yellowing of the NC itself. And moist there is no danger of fire--that's how it's shipped/stored. Possibly yours has stabilizer (usually diphenylamine) added to scavange any nitrogen oxides that might be released. I've got a pound that I've had in the freezer (sealed wet) for several years, which looks as white as the day it arrived. You can easily extract a small amount and dry it off and see how it burns. If it burns like guncotton does, rapidly disappearing with little visible gas and essentially no solid residue, then you can be assured that it remains high-quality. If there is residue, that would suggest that it has lost some of it's nitration status, but might still have utility. Unless it has a funny odor, has changed color, or is emitting reddish gasses, then safety is not really a concern as long as you continue to store the bulk of it (anything you're not testing/using) under water.I still have a pound of dry NC (well moistened with water) at least 12 years old now. Is it still safe? Its white and doesn't smell funny...
spreadsheet please! lolI am testing pyrogen mixtures this weekend and have 100 blanks made. My goal is to make 100 igniters to figure out how much it costs me and if it is worth my time to make them or continue buying them. I have a dozen or so recipes to try.
Tim runs PCS and is a good gent to do business with. If it's shown online, it's available, and he's pretty responsive to e-queries if you have any.https://www.pyrochemsource.com/Nitrocellulose_p_120.html
Since I have a pint of good 25% NC lacquer I've never used this source before but if the description is correct it should be high quality NC. Interesting that they ship it under 30% IPA rather than just water.
Acetone is great but evaporates very quickly--to me this is a plus not a minus for "starter" dips, but for rolling out and cutting dragon eggs (fireworking) you usually screw up the first time or two, especially if you don't have an (acetone-safe) spray bottle at hand. For a slower evaporating thinner, many use MEK (methyl ethyl ketone), which is sold in cans right next to acetone at HD, Lowe's, and WallyWorld, for about the same price. It gives you more working time and is not all that worrisome, but as always, including with acetone, work with a window open and a fan or outside.I still have some FireF NC that "rolls" in the cans so I expect I'm o.k.
I got too many "starters" I made in the past so I don't have to break into the cans yet and throw some thinner in to make some more starters. (Probably acetone is best but maybe toluene might get by?) Respondents on this please?
I spent 4 years dinking with igniters in the old days during the wintertime along with waiting for the epoxy to dry on my rockets fins and such.
ANY igniter formula that works to get one's rocket to fly is the one to use! Period! Arguing about it is like pi$$ing on the toilet seat to tick off ones wife!!!!!!! (I'm a widower now so I can say that)
Putting formulas in the restricted Research section is Kosher.
I have a variety of igniters I made many years ago and I, out of habit, still put one to three "breaks" in my igniter heads with two hands just before launch. Lets the builtup of gases out just before the igniter catches and flares. Don't have do this with commercial igniters but I'm ignorant and "cracking the heads" works with what I made as off-nominal as they may be!!!
Kurt Savegnago
Though potassium nitrate is thought to be mildly hygroscopic, it really isn't all that much. Perhaps 2-3% max water weight usually, though a bit more in super high humidity over time. I uploaded a US Army study of nitrate water absorption over many months last week, when they were testing alternate flash powder formulations for artillery simulators that were nitrate based (cheaper and less polluting than standard moderately-toxic perc formulations); you can easily find this report with a quick search.I tested igniters this weekend. I need to dry my Potassium Nitrate but they worked well. I am shocked how well ABS slurry worked as a dip.
Nice testing. Your Mg might have taken fire better if you'd included some supplemental oxidizer--Mg alone in air will burn hot but not very vigorously in those quantities. Even adding 5% Mg to your BP will give a noticeable enhancement. But Mg is a super reactive metal when fine-grained, and is more prone to chemical interactions than MgAl or Al, especially in the context of humidity/moisture, which could affect performance and degrade with long-term storage. I prefer to use MgAl alloy (-60 mesh; dust mixed with granules) or even just straight Al. What mesh-size was your Mg? And what BP were you using?There are a lot of suggestions in this and other threads about igniters/starters, but I wanted to test some options myself. I tested the following four igniters variations, all using Estes old igniters as the base (not the new StarTech igniters):
1. Stock Estes igniters.
2. Stock Estes igniters dipped in Testors silver paint.
3. Stock Estes igniters dipped in Testors silver paint and BP.
4. Stock Estes igniters dipped in Testors silver paint and magnesium shavings.
I ran one test of the four side-by-side to see how they compared to each other.
I then ran one test of 3 of each modified igniter side-by-side. I wanted to determine if any would be good for clusters. I love clusters and you want consistent ignition in terms of the time it takes to ignite, as well as a vigorous burn.
First test, comparing all four against each other.
View attachment 465888
The silver paint is better than the stock igniters (I have been using them for a while now, none have failed to ignite a BP motor). The paint and BP dipped look to be a bullet proof modification, as expected. The magnesium dipped ignitors did not flash as much as the BP but burned much longer (more below from Test 5).
None of my Slo-Mo videos will upload correctly for some reason, I have no idea why, unless they are too large. I will just describe the rest of the tests.
3 Silver Paint Dipped Only - all three lit at the same time, so potentially usable for clusters.
3 Silver Paint & BP Dipped - all three lit at the same time, vigorously. There was BP covering the paint top to bottom. In the slo-mo you can see the BP ignite at the top of the igniter and burn downwards. Likely far more than necessary. In my next test with this modification I'll dip just the tip in BP. I suspect it will be sufficient.
3 Silver Paint & Magnesium Dipped - all three lit at the same time, but not nearly as vigorously as in Test 1. My initial conclusion is that while you can get a really long burn with magnesium shavings, the vigor of the ignition is more dependent on the quality of the dip. Magnesium dip might be a good alternative for enhancing composite motor igniters for motors that are hard to start (i.e., Mojave Green). That would require a lot more testing.
One of my key objectives was to determine whether any of these would be an alternative to buying 3rd party BP motor "starters" (MJH Technologies). My conclusion is that Estes igniters that come with their motors, enhanced with paint and BP, should work well for clustered BP motors.
I'll run another set of tests with StarTech igniters (need to buy some) and StarTech igniters enhanced with paint and BP sometime this summer. I ordered some old school ping pong balls from Amazon and will add that to the test mix, as well. I got a gross of PP balls on Amazon for $10; enough to last several lifetimes.......
Nice testing. Your Mg might have taken fire better if you'd included some supplemental oxidizer--Mg alone in air will burn hot but not very vigorously in those quantities. Even adding 5% Mg to your BP will give a noticeable enhancement. But Mg is a super reactive metal when fine-grained, and is prone to water interactions that could affect performance, especially after long storage. I prefer to use MgAl alloy (-60 mesh; dust mixed with granules) or even just straight Al. What mesh-size was your Mg? And what BP were you using?
You'll probably notice an improvement with your celluloid PP balls vs other plastic binders (yuk) but why not use smokeless powder for about the same price?. A gross of Chicom PP balls is about 3/4 pound. That should make a lot ofigniters ahem "starters". But a pound of smokeless is not much more and has better burn characteristics--it's not half camphor which is a pretty slow fuel. Made to burn, not bounce!
Mike has the right of it, especially for BP motors; if they can usually be lit by the stock starch starter, almost any improvement will work a treat. It doesn't take much to set them off. If I were doing lots of BP motors I'd do the Testors (or almost any other silver paint, as they usually use powdered aluminum) and call it good. Don't over-think what's already been done, don't re-invent the wheel. Mike's shown it. Stick a fork in it and call it done. How much does a tiny vial of silver paint cost anyway, and how many starters are to be made?There are a lot of suggestions in this and other threads about igniters/starters, but I wanted to test some options myself. I tested the following four igniters variations, all using Estes old igniters as the base (not the new StarTech igniters):
1. Stock Estes igniters.
2. Stock Estes igniters dipped in Testors silver paint.
3. Stock Estes igniters dipped in Testors silver paint and BP.
4. Stock Estes igniters dipped in Testors silver paint and magnesium shavings.
$3.14 on Amazon and thousands...How much does a tiny vial of silver paint cost anyway, and how many starters are to be made?
You will like it, there is a thread about that pyrogen by jsdemar, there is a mixing and sizing spreadsheet I made for BKNO3-V in that thread. put in the motors core dimensions and it will spit out the weight of pyrogen needed for that motor. If you only want to mix enough for a couple of igniters it can give you those component measurements as well.I got some ProCast to play with for a couple large clusters - expecting greatness : ) Viton, Boron, and KNO3.
Cheers / Robert
Unsure how QD could get old, unless you have an atmospheric water issue with your acetone. It's just KNO3 and coated Al with a little charcoal added (this is not a research topic--the MSDS is freely available). And all of those by themselves are not really subject to degradation, when dry. When using that combo for wet compositions (water-wet), it's common to add 1% boric acid to the wetting solution to protect Al from unwanted reactions with nitrate (Al can reduce nitrate to amides, which can subsequently react with the Al in an exothermic reaction that risks spontaneous heating/fires; boric acid minimizes this by reacting with the very basic amides to form less insidious ammonia and a borate salt). But this is with water. Which is to be avoided. If your acetone absorbed water (it loooooves atmospheric water) then wet nitrate: 1) will easily corrode your wires, but that wouldn't be instant, and 2) might degrade your nitrate and reduce your compositions oxygen-providing capacity. Both of these are common once water, even just a little bit, enters the scenario. Are you dipping bare wire or coating an established pyrogen to soup up commercial starters?My old Quick Dip seems to have lost its punch after hydration with acetone for the second time. I happen to have on hand some atomized aluminum powder left over from my days of glass bedding rifle stocks. The Aluminum powder or Atomized steel powder was mixed with bedding epoxy. It added strength to the bedding compound. How about if I add say 20% of the AL to the powdered Quick Dip then rehydrate with acetone and dip away? Any thoughts?
My pleasure. That mix is pretty simple to replicate a fresh batch of. Stuff like Procast requires a little more up-front investment... Little chemistry details sometimes make the difference in complicating a simple mix, though. What's that old saying about "keeping your powder dry"? It applies to acetone, too--that stuff's an atmospheric humidity sponge :=}Thank you for sharing the info. I am dipping bare wire. I have not considered how atmospheric water can play such a big part in degrading nitrate. There's much more to this than I had assumed. I'll move forward with experiments and keep asking questions. Thanks again.
There are a lot of suggestions in this and other threads about igniters/starters, but I wanted to test some options myself. I tested the following four igniters variations, all using Estes old igniters as the base (not the new StarTech igniters):
1. Stock Estes igniters.
2. Stock Estes igniters dipped in Testors silver paint.
3. Stock Estes igniters dipped in Testors silver paint and BP.
4. Stock Estes igniters dipped in Testors silver paint and magnesium shavings.
3 Silver Paint Dipped Only - all three lit at the same time, so potentially usable for clusters.
3 Silver Paint & BP Dipped - all three lit at the same time, vigorously. There was BP covering the paint top to bottom. In the slo-mo you can see the BP ignite at the top of the igniter and burn downwards. Likely far more than necessary. In my next test with this modification I'll dip just the tip in BP. I suspect it will be sufficient.
3 Silver Paint & Magnesium Dipped - all three lit at the same time, but not nearly as vigorously as in Test 1. My initial conclusion is that while you can get a really long burn with magnesium shavings, the vigor of the ignition is more dependent on the quality of the dip. Magnesium dip might be a good alternative for enhancing composite motor igniters for motors that are hard to start (i.e., Mojave Green). That would require a lot more testing.
BP is FFFFg. The Mg was a trial effort using shavings from a Mg fire starter, not the most scientific effort, but informative.
Testors paint has Al in it, which is why the combo with BP seems to work well in my tests.
As for the PP Balls, I want to try it out and see for myself. Learning by doing.
Smokeless powder may be fine, but I don't think I need it when I already have BP and it works for this purpose.
The only inhibitor in NC PP balls is the camphor that is used to solubilize NC and shape the ball. It also acts as a stabilizer to minimize nitrate shedding/reactivity of the celluloid NC. The celluloid in PP balls is of low nitration levels (probably around 10-11% nitrogen, max) and would never ever go bang from smacking it with a paddle. Even if your balls were made with explosive-quality NC (nitrogen content in the 13%s) with zero stabilizer, they still would never detonate, or even ignite, from a paddle smack. Or a hammer smack. It takes a lot of initiating explosive force to detonate NC, and low-nitration celluloid PP balls can not be made to explode under any circumstances. If you put a blasting cap into a pile of PP ball-derived celluloid (mostly low-nitrogen dinitrates), the only thing that will detonate is your blasting cap. Period. With respect, suggesting otherwise is perpetuating mistaken understandings of NC characteristics. But yes, PP balls are an (imperfect) substitute for the high-nitration NC in smokeless or pure form; at least it is reasonably flammable, unlike a lot of plastics in some commercial dips and paints.I did PP ball lacquer very early on in my career and it does work fine but the components one puts into it really matters. Like KNO3,Mg etc.
One has to remember that there are inhibitors in PP ball plastic so the balls don't go "bang" when one hits them with a ping pong paddle. It still works if one doesn't have a resource for real NC lacquer.
Kurt
Kurt
I did PP ball lacquer very early on in my career and it does work fine but the components one puts into it really matters. Like KNO3,Mg etc.
One has to remember that there are inhibitors in PP ball plastic so the balls don't go "bang" when one hits them with a ping pong paddle. It still works if one doesn't have a resource for real NC lacquer.
Kurt
Kurt
The only inhibitor in NC PP balls is the camphor that is used to solubilize NC and shape the ball. It also acts as a stabilizer to minimize nitrate shedding/reactivity of the celluloid NC. The celluloid in PP balls is of low nitration levels (probably around 10-11% nitrogen, max) and would never ever go bang from smacking it with a paddle. Even if your balls were made with explosive-quality NC (nitrogen content in the 13%s) with zero stabilizer, they still would never detonate, or even ignite, from a paddle smack. Or a hammer smack. It takes a lot of initiating explosive force to detonate NC, and low-nitration celluloid PP balls can not be made to explode under any circumstances. If you put a blasting cap into a pile of PP ball-derived celluloid (mostly low-nitrogen dinitrates), the only thing that will detonate is your blasting cap. Period. With respect, suggesting otherwise is perpetuating mistaken understandings of NC characteristics. But yes, PP balls are an (imperfect) substitute for the high-nitration NC in smokeless or pure form; at least it is reasonably flammable, unlike a lot of plastics in some commercial dips and paints.
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