Many people have bought the spot welder controller. Some have built very nice spot welders with this, see the following examples:
Spotwelder from Antoine Dassenoy
https://www.kolins.cz/li-ion-spot-welder/
Spotwelder from Tom Weeber
Tom Weeber has built a very professional version of the spot welder:
High power spotwelder from Eero Nevalainen
An external SCR power block is used here:
