A spot welder can be used to permanently attach small pieces of (mostly ferrous) metal without the need for screws, rivets or adhesives. The actual science of optimizing a spot welder is pretty deep, but at the end of the day all you’re doing is heating up metal until it flows, so as long as the tool does that you can get some home shop use out of it…particularly if it’s made out of like $10 worth of materials and runs on household current. BTW, don’t mess around with high current devices unless you know what you’re doing and take all the appropriate safety precautions (like not standing in a puddle).
Here Grant Thompson of TheKingOfRandom.com explains how to make your own.
More after the jump
That project and the associated video were inspired by Steve Watkins’ Hack-a-day post.