Filament wiring for motor starting.

[TimothyG]

I had a thought of passing one of the old Aerotech flat wire igniters between a coupler and airframe for wiring up a near min dia mid power rocket. Has anyone used flat, foil type wiring for this in the past with any success or failure? Also if it has been done is there any decent sources for wiring instead of canabilizing old igniters?

 

[Steve Shannon]

I had a thought of passing one of the old Aerotech flat wire igniters between a coupler and airframe for wiring up a near min dia mid power rocket. Has anyone used flat, foil type wiring for this in the past with any success or failure? Also if it has been done is there any decent sources for wiring instead of canabilizing old igniters?

Alarm wiring:
https://sewelldirect.com/ghost-wire...MI-Pjr_9Ch4gIVtyCtBh2abQT5EAQYAiABEgLyNPD_BwE

 

[Adrian A]

I tried doing that a few years ago and found it to be too fragile. You can get adhesive-backed copper foil tape from hobby stores. I switched to head end ignition for airstarts, which has its own challenges and safety issues, but they can be overcome with thoughtful design.

 

[TimothyG]

Steve that’s exactly where my thoughts were on this. Just didn’t know what I was thinking about in particular. Thanks.

As far as head end igniters I don’t have enough experience with staging yet to even consider giving it a shot.

 

[Steve Shannon]

Steve that’s exactly where my thoughts were on this. Just didn’t know what I was thinking about in particular. Thanks.

As far as head end igniters I don’t have enough experience with staging yet to even consider giving it a shot.

There’s foil conductors meant to be applied to windows to detect glass breaking. It’s deliberately fragile so it will immediately separate when the glass breaks. I would not recommend that. The other is a flat conductor used to run to speakers or other devices under the carpet in a house. Here’s another source. If you look at the bottom of the page there are other alternatives that might work too.
https://www.amazon.com/Ghost-Adhesi...ocphy=9021317&hvtargid=pla-494959285087&psc=1

 

[SparkyVT]

https://www.adafruit.com/product/1128

I used foil wire from adafruit to do what you suggest. It worked great and was not brittle. In my technique I cast three halves of a pyrotechnic pellet into the smoke grain and used an ematch to light them, which lit the motor. Started an M motor at 7,000 ft no problem

 

[prfesser]

Copper foil might work well, I dunno, but I would avoid using Copperheads for this purpose unless you're going to use two separate ones for the conductors. Copperheads had a fairly high failure rate, partly because cutting the foil to size often left tiny bits of copper at the edges that would short out the current.

Best -- Terry

 

[TimothyG]

My idea is going to be using the bt60 tubing from Mach 1 rocketry. Their coupler is the perfect size motor mount for 38mm. The plan is do a near min dia two stage with the conductive foil running down opposite sides of the airframe between the coupler and airframe. This would separate and insulate the motor casing as well as the two leads from each other. This is very much still spitballing stages but I didn’t know if the idea had merit. Thanks for the help everyone.