Ran a couple of additional tests for my cut down circuit and I have decided to change the batteries.
Initially I was trailing two banks of 4 x AA’s in parallel giving about 6 volts. This seemed to be enough to heat the wire. However I hoped for a better solution.
Firstly I would have needed 8 fresh batteries which adds extra weight, and I still wasn’t getting the wire glowing red.
So tonight after stupidly dropping the AA battery holder and cracking the case, I decided to run a test with a couple of 9 Volt Batteries and wow, so glad I did.
With two 9 volt batteries in parallel the wire glows bright red and cut through my test twine like butter. So I think I’m moving in the right direction,
I should probably also run a test with a single 9v to see if I get a similar result. Happy for anyone to offer other suggestions for a cheap simple battery source to get that Nichrome wire red hot.
So far the cutdown system is partly fixed to a PCB
So far I’m happy with the circuit. The relay is soldered in place, and I still need affix a few of the other components but its looking good. Relay also seems to hold up to the current.