Deployment charges setting each other off?

[danielhv]

Just thinking about something....

My punisher 3 is a HEDD setup, and I'm using the glove fingertips for my charges... But if both the primary and secondary charges are in the nose cone for instance, where there is already a lack of space, is there concern for the primary charge inadvertently setting off the secondary charge next to it? Just don't want my 1g load to become a 2.5g load all of a sudden...

 

[teepot]

I have the same question. I also use the glove tip method. Fill the glove tip and then wrap with tape. The main and backup charges are only an inch or so apart. I've seen sympatric detonation with high explosives. When I set up an Ebay recently I started wondering if it could happen with our ejection charges.

 

[Voyager1]

You do need to separate them physically and preferably use a nomex blanket or heat proof barrier between the packed glove tips to reduce the discharge from one igniting the other. Preferably, you would use charge canisters (vials or charge wells) to provide better isolation.

 

[teepot]

Thanks.

 

[Jmhepworth]

When I use glove tips for charges, I zip tie the tip closed, cover everything with electrical tape, and then cover the electrical tape with masking tape (mostly so I can write the size of the charge on the masking tape). I’ve never seen an indication that one set off the other, even in a 54mm or 76mm body tube. I nearly always see or hear both separately, so one setting off the other is not something I worry about.

 

[Titan II]

All of my rockets but two (38mm-5.5"), use finger tip charges and no charge wells. I just wrap the charge with a layer or two of duct or masking tape. I have never seen any indication of one setting off the other.

 

[tfish]

Yes, I've had that happen. I test fly up to 4 altimeters in one rockets.... to test several altimeters at once for STEM stuff. (And no I don't use 8 full charges some are just ematchs and always made sure they were as separated as much as possible. I was using glover fingers to.
I switched to balloons and have not had that problem. I also now ties off the balloon and then slip the balloon back over for it..to make them double walled.

This is the brand and size I use up to 3g.

They're pretty thick and durable. Yes color-coded for old guys.
blue- looking up at blue sky- apogee.
green- looking down at grass- main
Walmart has some good 7" round balloons for bigger charges.

Tony

 

[Neutronium95]

I've never had issues with charges setting each other off. I use glove tips, but wrap them in a ton of electrical tape to improve the confinement.

 

[cerving]

Several wraps of masking tape around each charge should alleviate your issue. Never had this happen.

 

[Donnager]

I haven't either.

If you want to shield the other charge, use something thicker, like surgical tubing. Less flaming particulates. You may get the benefit of (more) complete combustion of the charges, also.

If you switch, go ahead and ground test those.

 

[RocketflierVB]

Aluminum HVAC Ducting Tape. Amazon has a roll for 18ish bucks