Mortartube Posted October 14, 2011 Posted October 14, 2011 Hi, Can anybody please recommend a prime to light Shimizu Golden Wave No 3? I have no silicon. I do have Mg/Al, Al and Titanium sponge that might make good heat conductors. Also have Pot Perc as probably the best oxidiser to use. I have tried Sponeburghs Pinball prime. It will occasionally light these stars on the ground, but the prime usually burns off and the star glows a bit and then starts burning. Fired from a star gun, I can see the prime burn off as the star fires up and then it blows blind. The only other possibility is that the stars have become driven in from priming. I used dextrin in the prime instead of red gum (which was mentioned as an acceptable swap in the priming formula).
Mortartube Posted October 14, 2011 Author Posted October 14, 2011 Sorry about the big gap at the top of the last post. I tried to include a table, which went haywire, and although the table doesn't show up on the post, I can't delete it in the edit.
Potassiumchlorate Posted October 14, 2011 Posted October 14, 2011 Magnalium/red iron oxide? I have the same problem with my own stars, even stars that are supposed to ignite much easier. Even my parlon stars, that are primed with KClO4/red gum/silicon, 70:20:10, are often blown blind. I estimate that only about 70% of my stars ignite, except for BP type stars and organic chlorate stars, where almost every single star ignites.
fredhappy Posted October 14, 2011 Posted October 14, 2011 (edited) Hi, To light silver wave and other high Al content stars reliably your best shot would be to use step priming. Basically you apply 2 layers of prime. The first layer of prime consists of 50% of the silver wave compo and 50 % hotprime. Since you have KCLO4 pinball prime wasn't a bad choice to begin with .Apply a 1 mm layer of the 50/50 hotprime/compo mixture. After this layerjust add another 1 mm layer of pure hotprime. On top of this layer a simple dusting with meal powder is sufficient. Titanium doesn't really work to make your prime burn much hotter, it just throws a lot of large sparks and doesnt' help much with ignition. Magnalium is a better choice. What is the mesh size of your magnalium? I'd really recommend getting some silicon. How do you apply your prime? Do you use a starroller? Are the stars cut, rolled or pumped?Shimizu is an old book, he specifies red gum as a binder sometimes. In this case just ignore and use dextrin, for prime 3.5 % is enough . Also, the silver wave formulas mentioned in his book are somewhat old fashioned. edit: I read you posted a silver wave formula containing realgar. Do you use this composition or was this just an example? Edited October 14, 2011 by fredhappy
californiapyro Posted October 14, 2011 Posted October 14, 2011 veline superprime kicks ass, it's thermite/kperc based. do you have dichromate?
fredhappy Posted October 14, 2011 Posted October 14, 2011 (edited) veline superprime kicks ass, it's thermite/kperc based. do you have dichromate? I am sure the veline prime works, but even many commercial firework operations refuse to use dichromate. A simple fencepost prime or pinball prime is sufficient for almost all stars. I personally like the fencepost type, since it is easy to make and will even light my silver wave stars with a single layer. I'd rather use some diatomaceous earth and silicon . I see no real reason to use such a toxic substance for such a trivial composition , it's just prime. Edited October 14, 2011 by fredhappy
dagabu Posted October 14, 2011 Posted October 14, 2011 I am sure the veline prime works, but even many commercial firework operations refuse to use dichromate. A simple fencepost prime or pinball prime is sufficient for almost all stars. I personally like the fencepost type, since it is easy to make and will even light my silver wave stars with a single layer. I'd rather use some diatomaceous earth and silicon . I see no real reason to use such a toxic substance for such a trivial composition , it's just prime. I wholeheartedly agree, the only thing I use dichromate for is strobe rockets, they just will not work without it but fencepost or pinball prime will light anything that should be lit. -dag
Seymour Posted October 15, 2011 Posted October 15, 2011 In primes you can easily skip dichromate with near negligible effect, especially if you replace it with another suitable catalyst (MnO2, CuO, Fe2O3... ) ...that is, unless it's there to protect Mg or MgAl from Ammonium perchlorate.... but AP based primes would be news to me.
californiapyro Posted October 15, 2011 Posted October 15, 2011 in the words of the creator, it's used as a "catalyst and secondary to protect magnalium". I only use it when doing amperc stars, where a bp/silicon can't be used. He states that adding the dichromate while prime is in slurry reduces the hazard. I agree for the most part, and it's always best to avoid toxicity when possible
Mortartube Posted October 15, 2011 Author Posted October 15, 2011 (edited) Hello again, I have no dichromate. My Mg/Al is approximately 100 - 120 mesh. It was given to me in mixed grades which I have sieved. Luckily I have only made a small batch of these stars so not too much is wasted re chemicals. The first post that mentions realgar went horribly wrong. I basically tried to paste a table into my post from the PFP database that had the metallic firedust stars listed, so I didn't have to type in the formulae. It didn't work. Everything got scrambled. The formula I used is below. Shimizu Golden Wave No 3 KNO3 37 S 9 Al Flake 47 Boric Acid 1 Dextrin 6 Wet 35% Alcohol The stars are 16mm pumped stars. I will step prime them and see if that helps Thanks for your advice Edited October 15, 2011 by Mortartube
fredhappy Posted October 15, 2011 Posted October 15, 2011 (edited) Hello again, I have no dichromate. My Mg/Al is approximately 100 - 120 mesh. It was given to me in mixed grades which I have sieved. Ok, again, I stress: no need for dichromate. The mesh size of your Mg/Al is also a bit too coarse , but I would add it to your prime anyway since it does ramp up the combustion temperature . 230-270 mesh is a good size for Mg/al and a versatile size too. Can be used for prime, colour stars, crackling and so on. Just place your pumped stars in a cardboard box. Spray and spinkle and roll and shake with prime until all your stars are somewhat evenly coated. Also, let every layer dry first before aplying the next one. Check the thickness of the prime layer by cutting a star in half. Hope this helps a bit. Edited October 15, 2011 by fredhappy
californiapyro Posted October 15, 2011 Posted October 15, 2011 yes, sorry if I misled you mortartube. fred, can you specify whether he should wet the stars or the prime?
fredhappy Posted October 15, 2011 Posted October 15, 2011 yes, sorry if I misled you mortartube. fred, can you specify whether he should wet the stars or the prime? Spray and sprinkle refers to the use of a spraybottle for adding a fine waterspray, and then sprinkling the prime composition on the stars. First spray the stars a couple of times with a solution of 80% water/ 20% alcohol, whilst rolling them around a bit. Then sprinkle on the prime and rol the pumped stars around a bit while doing this. Repeat until adequate prime layer is applied.
warthog Posted November 7, 2011 Posted November 7, 2011 can you obtain the stuff you don't seem to have? I have found that as long as there are no contradictions, Eugene Yurek's "Fence Post Prime" will light ANYTHING! If that doesn't do it, Lloyd Sponenburgh's "Pinball Prime" certainly will. If you need the formulae, I can post them, but I will ask the two of them if it is OK first and then come back here and do so if possible. I use these two primes exclusively now, except for those compositions that are incompatible.
psyco_1322 Posted November 8, 2011 Posted November 8, 2011 Try this prime on some unprimed stars. No guarantees it will light them, but I'd be curious to know if it would. SI PrimeKNO3 - 20Airfloat - 5Sulfur - 3Diatomaceous Earth - 1.5Dextrin - 2 Hand mix, apply straight to stars with your favorite water mix.
Recommended Posts