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Charge Canister Ematch ???

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Lowpuller

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I've done dual deploy in the past using latex finger tips for charge canisters.

This time I want to use hard canisters attached to the bulk head. I have been considering using 38 or cut 30-06 brass but I have the following concern:

ImageUploadedByRocketry Forum1476666056.301436.jpg

I'm worried the metal on the ematch base will contact the side of the canister and create a short robbing enough current to keep the ematch from burning. I could tape the base of the ematch but I've not heard of anyone doing this but I have heard about a lot of ematches failing.

Here you can see the metal on the igniter:

ImageUploadedByRocketry Forum1476665869.705568.jpg

Here you can see the two leads and the thin layer of insulation in between:

ImageUploadedByRocketry Forum1476665919.782827.jpg

If I use plastic charge canisters that are epoxied in place this concern goes away. I could also use the plastic specimen bottles but I don't have any.

Thoughts,ideas, suggestions......
 

mpitfield

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I always leave the red cover on the e match and I have used conductive canisters without any issues. I do trim the red cover to the point where it is even with the top of the match head, but I doubt this is even necessary.
 

GregGleason

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I'm not sure it's an issue.

However, what about putting some masking tape over it? Would that work for you?

Greg
 

markjos

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Leave the cover on the match. Push the open end into the BP, you'll be fine. Ground test, of course.

Mark
 

Handeman

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I leave the plastic cover on the ematch as it was intended. I also use copper 1/2" and 3/4" pipe caps as charge holders. I've had well over 50 flights without a problem. I think you may be looking for a problem where none exists.

Just fold the wire over into the the cup and tape the wire to the outside. Add your powder, dog barf to fill things in and masking tape over the top.
 

blackjack2564

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I've been wrapping a small strip of tape over the solder.
Only been doing this when using 2 matches per charge, when using single altimeter & when charge is less than .5 [1/2] gram BP.

Put powder in canister FIRST, then match then barf & tap shut. For high flights. Push pin through tape, so no pressure build up when flying over 20,000 ft.


DSCN5884.jpg DSCN5886.jpg
 

Lowpuller

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Do you use the straw as your canister?

Do you have pics of a completed charge?

Thank you for the info
 

OverTheTop

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I put a short length of heatshrink tubing over the metal area of the eMatch and back to the wires, then carefully shrink it in place. Don't get it so hot that it threatens to set the match off. Never had one go off, but safety glasses are a must. I keep it at arm-length while shrinking it too. Safety first!

All eMatches have always fired for me, so I don't seem to be doing them any harm treating them that way.
 

rharshberger

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Make sure and round the lip of your charge canisters though, so a burr or sharp edge doesn't cut through the wire. I too use metal charge holders and generally pour some of the powder in, insert ematch in center then the rest of the powder, tamp lightly, cover with dog barf and pack it down, then tape with two or three layers of white (original type) masking tape.
 

blackjack2564

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Do you use the straw as your canister?

Do you have pics of a completed charge?

Thank you for the info

No..... I put match in aluminum canister on bulk plate.

No, they are pretty self explanatory.

"Put powder in canister FIRST, then match then barf & tape shut. "

I want my match on top of BP, so BP must go past/through the burning match. My canisters are long and skinny, like small rifle barrel.

All that said, for everyday sport flying, I just use BP in finger tips.
 
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ksaves2

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If using two matches per canister, put tape around the base of one match so there is no danger of shorting. Acts as insulator Kurt
 
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