Hero,
I want to build your circuit possibly using a HUF MOSFET from Maplin (14mOhm, 60Amp).
Could you add a bit more detail please, like where would you place the on/off switch and how does the circuit work - do you short circuit the capacitor with a resistor to switch the FET on over 1 or 2 seconds?
I would also like to have an option to fire a big relay to give more power.
I am using it to drive a 350W 24v motor in a child's go-kart. I had just been using a 40A relay, but the is a massive jolt when you start which puts a lot of strain on the drivetrain and it has also burnt out the relay contacts
Thanks
Ben