Has anyone used a car battery/solenoid to spot weld? I was using a scooter solenoid till it stopped working and bought a 12v 250a atv winch solenoid. However, I cannot figure out how the new solenoid needs to be wired to get the setup functioning as it has 6 terminals rather than 2. Unfortunately, no instructions were included either. I got the idea from @darkkevind 
Hi, you can easily build a spot welder with a relay, intact I am using that one right now in a test build. You connect battery positive to red, and negative to black. You then connect positive electrode to blue, and the negative electrode to yellow. The other two terminals are for a momentary switch, and you can connect a momentary 12v switch to them
Perfect, that is just what I needed! You have either the green or black wire connected to a momentary switch then from the switch to the positive terminal of the battery? It seems like it doesn’t matter if you use either of those wires. Thank you for your help!
You have both the green and black connected, one to the positive of the switch, one to the negative, it doesn’t matter which color, there just needs to be a connection
I have a switch connected to the black wire coming out of the solenoid relay and then the other end of the switch connected to the positive terminal of that battery. I can hear the magnet completing the circuit.
Yes! Sorry, I wasn’t thinking straight. Yeah that’s right
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