Nitrate based prime on Ap stars

[cogbarry]

Does anyone have any experience here? I'm such a dope for not taking notes. Had a 4" inch shell with red stars (blesser's crimson #19) which had (I think) a prime layer of fence post and blond streamer layer on the outside. It was a nice shell and I would like to make more. The problem is, I've forgotten exactly how I made it. The stars (at least the cores) were made two years ago, the shell was built last year. I had used the primer blesser recommended with a layer of BP over that in the past and the stars blew blind.

 

I'm thinking I rolled a fence post prime over the AP cores using NC laquer/acetone for solvent and red gum as binder, then rolled the streamer layer over them. I beleive the NC laquer prevents the nitrate from leaching into the AP cores.

 

Anyone have an ideas or suggestions here?

[californiapyro]

what I do on my AP blue is roll about 1/16 of fencepost with 20% silicon, then straight bp out of the mill on top of that. it makes the stars unnecessarily large, but they never blow blind

[Potassiumchlorate]

I also use lots of hot prime on my stars. It's expensive, but if the stars are blown blind, all your work was in vain.

 

I haven't made many AP stars, except for tests, but I have used pinball prime with +6% silicon with good results. Another composition, that is nasty but hot is Hardt Prime #6:

 

Potassium perchlorate 37

Charcoal airfloat 30

Lead tetraoxide 22

Silicon 7

Dextrin 4

 

Oops, I see now that you asked for nitrate based prime, though I think perchlorate based is necessary to secure ignition.

 

There is of course Shimizu Igniter B:

 

Sodium nitrate 80

Charcoal airfloat 15

Sulfur 5

Dextrin +5

Edited May 17, 2012 by Potassiumchlorate

[cogbarry]

what I do on my AP blue is roll about 1/16 of fencepost with 20% silicon, then straight bp out of the mill on top of that. it makes the stars unnecessarily large, but they never blow blind

 

Thanks! I don't have my fencepost formula handy but I think it's only 5% silicon and 5% DE. In any case, it does contain potasium nitrate which according to blesser, requires something to seal core from nitrates seeping in. Hence the NC laquer. What do you use for a solvent.

[cogbarry]

I also use lots of hot prime on my stars. It's expensive, but if the stars are blown blind, all your work was in vain.

 

I haven't made many AP stars, except for tests, but I have used pinball prime with +6% silicon with good results. Another composition, that is nasty but hot is Hardt Prime #6:

 

Potassium perchlorate 37

Charcoal airfloat 30

Lead tetraoxide 22

Silicon 7

Dextrin 4

 

Oops, I see now that you asked for nitrate based prime, though I think perchlorate based is necessary to secure ignition.

 

There is of course Shimizu Igniter B:

 

Sodium nitrate 80

Charcoal airfloat 15

Sulfur 5

Dextrin +5

 

Thanks,

I wasn't specifically asking for a nitrate prime just ideas in general and I read there were issues using nitrate prime on AP stars. Not dangerous issues as I recall but issues with stars blowing blind.

 

What I really want is to figure out what I did the last time. Why can't you guys help me with that? Just kidding of course. Lesson learned, take notes, even if you don't know if it's going to work!

 

I know I used NC laquer/acetone for solvent and I know I used fence post. I'm not sure if I used blesser's perchlorate AP prime or not. I doubt it as I did this on the first batch and they blew blind. I think I rolled the fence post on but used red gum instead of the usual dextrin as a binder. Then the streamer comp. These stars started as 3/8" but were quite a bit bigger when done. They were a good fit in the 4" shell.

[Potassiumchlorate]

Thanks,

I wasn't specifically asking for a nitrate prime just ideas in general and I read there were issues using nitrate prime on AP stars. Not dangerous issues as I recall but issues with stars blowing blind.

 

What I really want is to figure out what I did the last time. Why can't you guys help me with that? Just kidding of course. Lesson learned, take notes, even if you don't know if it's going to work!

 

I know I used NC laquer/acetone for solvent and I know I used fence post. I'm not sure if I used blesser's perchlorate AP prime or not. I doubt it as I did this on the first batch and they blew blind. I think I rolled the fence post on but used red gum instead of the usual dextrin as a binder. Then the streamer comp. These stars started as 3/8" but were quite a bit bigger when done. They were a good fit in the 4" shell.

 

If I roll my stars with dextrin, I often prime them with a prime bound with NC-lacquer. The first NC-lacquer I made was from high nitrated cotton, made by myself. I used BP with +5% silicon and +10% German Black. Those stars weren't AP stars, of course, but Electric Magenta. They always ignite, though. That NC-lacquer was extremely inflammable.

[californiapyro]

if memory serves, fencepost is

 

75 kclo4

15 charcoal

10 red gum

+5% silicon

 

or something like that. no nitrate...

[MikeB]

Fencepost is actually

 

KNO3 65

Airfloat C 12

S 10

Diatom. earth 5

Si 5

Balsa C 3

 

What Cali posted is a hot perc based prime, might be Pinball with added metals. If you use that be sure to use an ignitor layer over it since it does not take fire very well.

[NightHawkInLight]

When using nitrate primes on AP remember that you run the risk of creating AN, thus ruining your stars. I don't know from personal experience how easily the reaction occurs because I've always avoided the combination. It would be cool to know if it doesn't give you any issue.

[californiapyro]

oh yes yes you're right, i meant pinball prime DOY!

 

and yes, I coat that with meal to finish the priming

[Potassiumchlorate]

When using nitrate primes on AP remember that you run the risk of creating AN, thus ruining your stars. I don't know from personal experience how easily the reaction occurs because I've always avoided the combination. It would be cool to know if it doesn't give you any issue.

 

Potassium nitrate is supposed to give trouble. Shimizu says that sodium nitrate is OK, hence the Igniter B. Above all sodium nitrate is cheap. If you have access to AP, KP shouldn't be a problem to get, but it's of course always more expensive than nitrates.

[Seymour]

Priming for AP stars does not need to be too crazy. So long as they are well formulated and have well powdered components (no sugary AP allowed!) AP stars being hard to light seems to be rare, and as such I don't think it's necessary to waste Silicon or Lead tetraoxide (though if you've got the Silicon at hand and are not precious with it, may as well use it...)

 

For the NC bound barrier between the AP and KN layers I would want to have a relatively good layer of it. Shimizu states "1-2mm minimum" in the context of AP strobes on page 224 of my F.A.S.T.

 

I've had 1mm described to me as a very thick prime, and in some contexts, like trying to pack several colour changes in to stars yet maintain a good star count in a small to medium sized shell, I could agree, and would probably arrange it so there's a NC bound effect composition doubling as a delay.

 

A few years ago I rolled some AP stars, bound with double base, with a KP buffer (also double base), and then rolled over that with a water based Black powder type slurry. After two years of open air storage the stars performed fine (though the strobe cores seemed a bit less bright), so I have good faith in NC buffer layers. Other binders (new and maybe ones we already use) will be as or more effective too, but (though parlon seems good) I'm not confident of any of them yet.

 

Sodium nitrate, due to the equilibrium favouring the AP staying as AP, and leaving the nitrate to be along with the Sodium, does not cause soggy stars in theory. In practice this cannot be relied on to be true, at least not without very high quality sodium nitrate. Even without any ion swapping with my favorite Ammonium salt, my Sodium nitrate prime on the AP never dried. In fact it got really soggy, and proved that if left soaking, the NC bound AP blues will forever now be yellows. I know I was asking for it with 98% agri grade Sodium nitrate, but I warn that you may be too unless you get some that's had another recrystalisation (or two).

Edited May 18, 2012 by Seymour

[Potassiumchlorate]

Bleser's New Blue is absolutely unbeatable in colour, maybe except for Paris Green blues, which isn't an option for most of us anyway. New Blue is Forget-me-not blue, while Paris Green blues are more towards indigo, though.

[cogbarry]

If I roll my stars with dextrin, I often prime them with a prime bound with NC-lacquer. The first NC-lacquer I made was from high nitrated cotton, made by myself. I used BP with +5% silicon and +10% German Black. Those stars weren't AP stars, of course, but Electric Magenta. They always ignite, though. That NC-lacquer was extremely inflammable.

 

I cheated, I bought mine.

[cogbarry]

Potassium nitrate is supposed to give trouble. Shimizu says that sodium nitrate is OK, hence the Igniter B. Above all sodium nitrate is cheap. If you have access to AP, KP shouldn't be a problem to get, but it's of course always more expensive than nitrates.

 

Blesser mentions this in his instructions for AP stars. I believe the NC is supposed to seal the core and protect it from the nitrate seeping in.

[cogbarry]

Priming for AP stars does not need to be too crazy. So long as they are well formulated and have well powdered components (no sugary AP allowed!) AP stars being hard to light seems to be rare, and as such I don't think it's necessary to waste Silicon or Lead tetraoxide (though if you've got the Silicon at hand and are not precious with it, may as well use it...)

 

For the NC bound barrier between the AP and KN layers I would want to have a relatively good layer of it. Shimizu states "1-2mm minimum" in the context of AP strobes on page 224 of my F.A.S.T.

 

I've had 1mm described to me as a very thick prime, and in some contexts, like trying to pack several colour changes in to stars yet maintain a good star count in a small to medium sized shell, I could agree, and would probably arrange it so there's a NC bound effect composition doubling as a delay.

 

A few years ago I rolled some AP stars, bound with double base, with a KP buffer (also double base), and then rolled over that with a water based Black powder type slurry. After two years of open air storage the stars performed fine (though the strobe cores seemed a bit less bright), so I have good faith in NC buffer layers. Other binders (new and maybe ones we already use) will be as or more effective too, but (though parlon seems good) I'm not confident of any of them yet.

 

Sodium nitrate, due to the equilibrium favouring the AP staying as AP, and leaving the nitrate to be along with the Sodium, does not cause soggy stars in theory. In practice this cannot be relied on to be true, at least not without very high quality sodium nitrate. Even without any ion swapping with my favorite Ammonium salt, my Sodium nitrate prime on the AP never dried. In fact it got really soggy, and proved that if left soaking, the NC bound AP blues will forever now be yellows. I know I was asking for it with 98% agri grade Sodium nitrate, but I warn that you may be too unless you get some that's had another recrystalisation (or two).

 

Thanks for this.

The only reason I'm somewhat bent on using the nitrate prime is because I am trying to replicate what I did in the past. I did use a pretty thick layer of prime. Therefore, I suspect it played a significant part in the star's effects.

[Mumbles]

If you want to keep things relatively the same, you can just swap out the potassium nitrate in the fencepost prime for potassium perchlorate. A member here has had good success with that. If you bind that with NC, you should have no problems layering a streamer over the top of it.

[cogbarry]

If you want to keep things relatively the same, you can just swap out the potassium nitrate in the fencepost prime for potassium perchlorate. A member here has had good success with that. If you bind that with NC, you should have no problems layering a streamer over the top of it.

 

Thanks Mumbles, that's great to know.