Which relay do I need?
perhaps something like this:







simulate this circuit &ndash; Schematic created using CircuitLab
improved version:







simulate this circuit

The relay is just an ordinary automotive headlamp/horn relay
the 30A fuse prevents damage to the cable to the machine from starting a fire and the 1A fuses do the same for the control circuit (allowing the use of smaller wire for those circuits)

pressing the stop button or the clutch cuts the power to the relay turning it off.

pressing the start button feeds power to the relay turning it on and then the relay feeds power to itself after that.

the 1A fuses can be 3AG fuses in in-line fuse-holders the 30A should probably be an automotive blade fuse in a suitable fuse block.

lever of the clutch pedal may suffice.







simulate this circuit

finally here's a simplified version. the start buttone will need to be a heavy duty type capable of running the machine.

the switch on the clutc need to be heavy duty, and as it is a switch to ground a simple contact that contacts the