Originally posted by rstaff3
Ack, was reading fast on the way to an errand, and oviously didn't parse Dynos post. I AM an advocate of protecting the ematches. I am NOT an advocate of most switches to power up the unit. An excpetion is the type shown by BHP.
A shunt is not a switch to power something up. It is a grounding bus between leads to a critical component, in this case one with a pyro charge. It does not have to be any more complicated than the alligator clip-on-ematch idea, or twisting (in this case, untwisting) two wire ends. The worst that can happen if you forget to unshunt the leads is it'll fail your continuity test before you launch it.
You DO test continuity before launching, right?
(That's a generic "you", rstaff3).
If it needs to be done before you fly and it's not safe if not done, you should be using a "Remove before flight" tag on it, whether it's something to actually remove, or a test to perform and the tag serves only as a reminder.
It is true that any additional steps add complexity. However, inadequate complexity, in being able to launch a rocket in an unsafe condition, is as much a problem.
BHPs idea is a good one.
I was thinking of soldering something like the tail end of a Copperhead to the two sides of the leads, and clamping an alligator clip on it to short them. That can be placed just inside a vent hole where it doesn't stick out but is easy to reach.