I did really need a spot welder though ... current limiting resistor to the battery while also holding a multimeter in place, or connecting a large variable-voltage power supply with current ...

Learn how to build a compact spot welding machine using a battery in this easy DIY tutorial. Spot welding is essential in various industries, including automotive, aerospace, and construction.

030 dia. flux-cored wire on 1/8-in mild steel. Battery power is monitored continuously to provide consistent welding voltage regardless of the charge level. The Trek's low battery shutdown feature ...