Originally posted by Dbarrm
So I need to find a diode that can handle the current. Put it in the same leg for each jack and all should be ok.
FWIW I used a very similar circuit.
I used the same 6A rectifier diodes that Radio Shack sells, which cost about $.50 each retail, except I got them at a surplus store. It's not a safety critical part in that if you burn out a diode you'll just lose continuity testing on that circuit. Buy some spares, solder on some quick connects, problem solved. I've had to replace two over the past four years or so, always after some ridiculous thing like a seven AP motor cluster....
However, I do have some suggestions.
First, you might want to put a relay between the launch button and the firing circuit. As it stands, you're using the launch switch--which IS a safety-critical part-- to handle all of the launch current, and it's going to have to be a very beefy and expensive switch to take that kind of abuse. If you instead get a 30 or 50 amp relay (a car horn relay would be just fine), you can use a pretty switch (mine's an old arcade game switch) for the launch button.
Second, it is always possible to get a welded relay, so to avoid nasty surprises you might consider putting a buzzer across the firing relay so it yelps if the relay is closed.
Third, consider splitting the console box and put the relay box (and the battery!) at the pad. You can connect them with 50' extension cords, which are about the cheapest wire you can find anyway. If you want, you can have continuity at the console, and still only need five extension cords to run six pads. You can use 110 volt plugs and receptacles for easy maintenance and relatively low cost.
Good luck with the project!
For what it's worth,