Buying a spot welder may cost you around $300 or more. But if you’ve got a microwave transformer tucked away in the dark and eating dust, then you may simply build it into this fine equipment with a little less than $20 for the cost of materials.
The mini spot welder is a plain metal ducting tool with simple construction. What prolongs the process and makes it hard is perhaps only the part where you have to clean the core of the transformer where the secondary coils wind. The rest is a breeze. Before getting excited on building one yourself, watch first.
source: Creative Channel
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