Posted 03 February 2019 - 01:56 PM
Posted 03 February 2019 - 04:03 PM
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"The art of fire is indeed the supreme art; for fire is at once the universal slave, the universal master."
Posted 03 February 2019 - 04:32 PM
Posted 03 February 2019 - 04:37 PM
Posted 04 February 2019 - 04:57 AM
The purpose of a break charge is to light all the stars before pushing them outwards. If you over boost the break then there is a risk that some to all of the stars will not light before they travel outwards.Your nitrate boost was slower than your flash boost, try reducing the boost even more, the stars must light before they spread out. Builders of big cylinder shells use a weak break powder with rice hulls or similar diluents.
Just a few times you want the break to start at the centre of the shell so you need to pipe the fuse fire to the centre in a cardboard tube and fit it with a flash bag in the centre but containing a very small amount of slow flash, say 0.1g of flash.
Posted 05 February 2019 - 04:45 PM
Who is building large cyliders, with rice hull diluted powder?
Posted 14 February 2019 - 01:00 PM
A few thoughts on your problem. I don't know how much experience or knowledge you have so please, don't take offense if anything I say is too basic for you. Poor containment (insufficient pasting/spiking or even poor quality paper) can cause poor breaks and bad ignition of the stars. The stars are simply flung out into the air before getting a chance to light. So then, you try boosting your break more to make up for the poor break caused by bad containment and just make star ignition even worse. I say all this because I agree with Dagabu; 4 grams of flash in the size of shell you described is an awful lot, which makes me think your experiencing exactly what I just described. In any case, even well made shells that are hard breaking shells always present a challenge to get 100% ignition of the stars and I believe every pyro goes through this problem early on, I know I sure did. Among other things, my best solution blind blown stars was a double layer prime. My first layer is a perchlorate based prime with aluminum and silicon. I then add a layer of finely granulated BP. Yes, finely granulated as it creates a rough surface that takes fire much easier. Good luck!
Posted 15 February 2019 - 06:36 AM
Edited by kingkama, 15 February 2019 - 09:23 AM.
Posted 21 February 2019 - 12:22 AM
Kingkama, try and double the amount of prime you are currently using. In my experience, not enough prime is often the problem. You will know when you are using too much flash when your stars break into pieces. I can use 5g of 70/30 in a 3" shell and get 100% ignition.
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