13 replies to this topic

[hst45]

hst45 Hot Prime:

70 KNO3
15 Charcoal
8 Dark Al
4 Redgum
4 Dextrin
3 Spheroidal Al
1 Boric Acid


I've been using Veline's Superprime with fine results, but I wanted to do something that didn't use the dichromate or the "wood meal". I wanted a prime that was hot enough to light Ammonium perchlorate blues, metal-fueled greens and reds, etc and didn't contain sulfur, for the obvious reasons. I've been using a similar version of this as a an intermediate prime to run interference between perchlorate and chlorate based star comps and a dusting of BP meal that of course contains sulfur, but I've found that this prime is easy enough to light that the BP meal is unneccessary. This seems to be hot enough to light anything that I've made, and yet easy enough to light that it takes fire without the extra step of a BP prime or step priming. Bind with water.

The math majors in the class will notice that this doesn't add up to 100 PERCENT; all too true, these are the raw numbers based on ratios, not percent, and represent the results of my experiments and are not meant to be percentages. As I went I upped this and deducted that, and this is the result. If you're hung-up on 100 feel free to round up or down to your hearts content. Try it, and I think you'll be pleased.

[Mumbles]

Might have been an oversight, but if you wanted something hot enough to light AP blues, why would it be based off of KNO3? It will take something a lot hotter than that to light sludge.

[Swede]

What is the function of the spheroid Al in that comp? Can it work well without it? I have none.

[pudidotdk]

KNO3 won't do with AP no matter how cheap it is.

KNO3+NH4ClO4->KClO4+NH4NO3

hygroscopic ammonium nitrate is formed. Therefore AP stars should be primed with potassium perchlorate.

[Bonny]

What is the function of the spheroid Al in that comp? Can it work well without it? I have none.

I think it burns slower than flake, so it will stay burning longer to help ignite the stars. You could try some granular Al or maybe a coarser flake if you have I guess. I think silicon might be even better than the Al though.

[flying fish]

Hey, here is a thread that applies to me! I was about ready to sell my Ammonium perchlorate as my pretty blue stars are obviously useless if I can't get them to light beyond holding a MAPP gas torch to them...

Still, like the others I'm a bit skeptical of the prime. Maybe it's ok if the stars are dry enough to prevent significant amount of chemical interaction? I'm wondering if there is any possibility substituting in KCLO4 instead of KNO3 would make for a working prime formula?

Also, why would you not want sulfur in an AP blue star prime? It is just going to wash out the color, or is there an incompatibility there?

Furthermore, isn't iron oxide also sometimes used in hot primes? I wonder what the addition of that could further increase the burning temperature (say for instance if I had some stars that were exceptionally good at playing Hard-to-light)

[tentacles]

flying fish: Have you tried the fence post prime for your devil stars? The biggest problem with 'fence post' is sourcing silicon. Difficult to ship.

[flying fish]

I have never tried silicon containing primes... but I'm tempted to find out what part of the computer chips are silicon and smashing them!

The company that my company shares a building with does microelectronics...probably based in silicon, so I wonder if they have some scrap that I can like...grind up or something. When I come in on Wednesday, I have to ask for information on their wafer packaging, fill up on De-iononized water with their DI machine, so what's asking for one more thing while I'm at it?!

[hst45]

So many questions, so let me tell you the tale of how I got to where I am with this.

My goal was to make a universal hot-prime that would light any of the stars that I make. Since I occasionally dabble with chlorate-based comps, I decided that sulfur was not to be used. My first comp was just 75/15/10 substituting redgum for sulfur, which didn't work at all well. I then decided to "hotten" this with some dark Al; still not good. This is the point where I added the boric acid since I was using aluminum and a nitrate. I added a bit of spherodial Al to give it a bit of extra long heat to light some of the hardest lighting stars, and this is where the research bore fruit. I tweaked the ratios a bit, and this seems to be the best that I've acheived.

Swede, flake Al would probably be a good substitute for the spherodial since it's the long, hot burn that seems to be the key to lighting hard-to-start stars. Maybe MgAl works too; I'll have to try that.

Pudi, if you're concerned of binding this onto AP based stars, what do you think about leaving out the dextrin and binding with shellac flakes and ethanol?

[frogy]

I don't know if you didn't realize, as Pudi said... AP and KNO3 are incompatible... NH4ClO4 + KNO3 -> NH4NO3 + KClO4... Simple Double replacement.

A thin Perchlorate prime in between would probably work, while still keeping the heat of this outer prime.

[hst45]

Damn. I STILL need the VSP as an intermediate layer..(sigh). Thanks frogy.

Or, plan "B", maybe a quick roll in NC lacquer?

[flying fish]

I don't know if you didn't realize, as Pudi said... AP and KNO3 are incompatible... NH4ClO4 + KNO3 -> NH4NO3 + KClO4... Simple Double replacement.

A thin Perchlorate prime in between would probably work, while still keeping the heat of this outer prime.

Now there's an idea. Are you suggesting just a simple KP intermediate, or would it also have additives to make it hot? Well I suppose if the layer is thin enough it shouldn't matter, right?

I attempted an arbitrary Meal/Speroidal aluminum star formula (80/20) recently, and apparently the aluminum percent was way to high, because these stars really left some extremely nasty slag behind (far worse than your typical Antimony sulfide stars). I bet they could do a pretty dang good job of lighting stuff! Though the brightness of it may wash out colors.

[frogy]

Hmm.. I'd basically use the Veline super-prime as the intermediate.

Obviously should contain KClO4, A fuel, A hot fuel, and some binders.

Superprime isn't really needed though.

Probably just a KClO4, MgAl, Charcoal, Red Gum, and Dextrin mix.

Maybe even drop the dextrin, and keep it Acetonte\100% alcohol bound with Red Gum.

A thin roll of NC Lacquer would also work... The film would eliminate, or extremely inhibit the replacement reaction. It's also nice that AP stars are not porous (in most cases), so the Lacquer won't be absorbed like crazy... Quite literally a think film should do it.

[Mumbles]

With AP stars I used a hot prime layer, and bound the green meal with NC lacquer. It might work to bind with an alcohol based binder or NC directly on the star. I think NC would be better. It should would at least work in the short term, probably wouldn't be very storage stable though. If you store stars, you could always make them, and just prime them as needed.