BAHume Posted June 23, 2016 Share Posted June 23, 2016 I made a small test batch of some Zinc spreader stars. I primed them with my Veline Hot Prime (while they were still damp) and let them dry for about a week. The prime lights quickly but fails to ignite the stars. I'm thinking about trying fence post prime. Any suggestions? Thanks! Link to comment Share on other sites More sharing options...
OldMarine Posted June 23, 2016 Share Posted June 23, 2016 The zinc granite stars lit easily with BP prime for me. I haven't made those you refer to but I would think a hotter prime should work.Post a formula so others can critique/help. Link to comment Share on other sites More sharing options...
AzoMittle Posted June 23, 2016 Share Posted June 23, 2016 (edited) Ya I've never had an issue with zinc stars either, mine are a slowed down BP with a healthy portion of zinc added. We could help more if you shared the formula you are using for your stars. Maybe try a thermite prime then the hot prime? (Credit to Mumbles and Lloyd for informing me of it, and credit to Shimizu for coming up with it.) Aluminium (Bright) 45Red Iron (II) Oxide 55Dextrin 5 Or Lead Tetraoxide 80Ferro-Silicon 20Dextrin 5 Edit: an easier way would probably be to step-prime it. Make up a batch of BP, for first coating of stars use 80% zinc star mix and 20% BP, then move to 60-40, then 40-60, then BP. Edited June 23, 2016 by AzoMittle Link to comment Share on other sites More sharing options...
BAHume Posted June 23, 2016 Author Share Posted June 23, 2016 I apologize for not posting the formula: 43.08 Potassium Nitrate 123.08 Zinc Dust 21.54 Charcoal 12.3 Sulfur The formula (Source:Pyro Data) called for binding with dextrin and water but did not specify the amount of dextrin to be used so I used about 4 grams for this 200 gram batch. Since my hot prime didn't work is there still a way to save this batch by re-priming over the hot prime? Thanks again. Link to comment Share on other sites More sharing options...
Mumbles Posted June 23, 2016 Share Posted June 23, 2016 Are you trying these on the ground or in the air? It's been a long time since I've made any zinc spreaders, but I seem to recall them behaving oddly on the ground. They were never difficult to light, however I think they behaved like some other fuel heavy streamers. They would barely burn on the ground or just make a cinder or ash. In the air they would burn fine due to the necessity for atmospheric oxygen. Link to comment Share on other sites More sharing options...
schroedinger Posted June 23, 2016 Share Posted June 23, 2016 Maybe they alse weren't dry after a week.Read this to solve your questions:http://www.skylighter.com/fireworks/how-to-make/zinc-stars.asp Link to comment Share on other sites More sharing options...
BAHume Posted June 24, 2016 Author Share Posted June 24, 2016 I actually lit one on the ground before constructing a test shell. That star lit just fine but when I fired the shell I realized something went wrong. So I test lit a couple more and realized that the prime burned away leaving the stars intact. I think I'm coming to the conclusion that maybe my batch was not completely dry and I just got lucky with the first test. I pulled my test star off of the drying rack and after it lit fine I stored the remaining batch in a ziplock bag with some silicon packets. I made the test shell with the stars that have been sitting in the ziplock for about a week. Mumbles is 100% right about them acting funny when lit on the ground. I guess I will try another batch and increase the drying time and step prime them. Thanks for the input gentleman. Link to comment Share on other sites More sharing options...
BAHume Posted July 3, 2016 Author Share Posted July 3, 2016 Second batch of Stars turned out great. Thanks for the advice!! Happy Safe, Fourth Of July Everyone. Link to comment Share on other sites More sharing options...
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