DIY spot welder from old microwave for making Li-ion 18650 packs with nickel strips. Uses bluetooth communication in custom Android app to adjust welding parameters ...

Just about everyone on here knows it’s quite possible to build one of these things using a re-wrapped microwave transformer ... than “hey look I built a spot welder!”.

Microwave oven transformer spot welder builds are about as common as ... including how to compensate for shrinkage and make allowance for draft. There are tons of tips to glean from these videos ...

This is my version of a DIY spot welder controller. It is intended for use with a modified microwave oven transformer, but may suit other applications too. I have included the PCB Gerber files, BOM ...