Powder charge problems

[Zeus-cat]

I test continuity before I prep the charge!

The problem with using Pyrodex and Christmas tree lights is that you need to check continuity AFTER you prep the charges. Because you pack the Pyrodex in on a bare filament you can easily damage the filament. I used to use this system and sometimes had a 50% rejection rate after loading the Pyrodex.

 

[Handeman]

The problem with using Pyrodex and Christmas tree lights is that you need to check continuity AFTER you prep the charges. Because you pack the Pyrodex in on a bare filament you can easily damage the filament. I used to use this system and sometimes had a 50% rejection rate after loading the Pyrodex.

I didn't use Pyrodex so I didn't have to contain it tight, probably less breakage just pouring BP in. But I still used two xmas bulbs in parallel with the BP. I relied on the altimeter check for the final "after loading" check.

 

[Garrace]

Hi I'm the one that started this thread and thought I would post a update. I have switched to only using the fmg? Ematches from buyrocketmotors $1 each. So far 100%. On the other hand with the light bulbs I did have one not fire even though it tested fine even on the launch pad. I'm thinking that maybe it shook loose in the socket during launch. I think those tiny wires are prone to contact issues. The motor backup charge deployed the drogue so no problem. But with the ematches being cheap and no hazmat and seem to be pretty reliable