{"id":5619,"date":"2019-01-13T19:48:21","date_gmt":"2019-01-13T18:48:21","guid":{"rendered":"https:\/\/kiube.se\/projekt\/?p=5619"},"modified":"2022-10-07T10:35:51","modified_gmt":"2022-10-07T09:35:51","slug":"spot-welder-for-batteritillverkning","status":"publish","type":"post","link":"https:\/\/kiube.se\/projekt\/5619","title":{"rendered":"Spot welder f\u00f6r batteritillverkning"},"content":{"rendered":"
Learnings from building a spot welder by Bart Oostenrijk<\/div>\n
see attached some pictures of the spot welder. I found that a long cable (like on the picture) causes too much power loss, so I made it into a very short cable instead. The inside is an old microwave oven transformer with the secondary coil consisting of only two windings, powered by a solid state relay (AC, zero-cross switching, 40A max). When you push the small push button on the handle, the transformer is engaged very shortly, and a high current will flow at a low voltage (about 4 Volt).<\/div>\n
There will be two successive pulses: one to ‘clean up’ and preheat the metals, and one to do the actual melting of the metals. The duration of the main pulse can be set by a potmeter.<\/div>\n
On the pictures you can see two brass bolts I used for the contacts, but they did not seem to do the work. I then changed to copper electrodes, and they seem to work better.<\/div>\n
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The SSR is controlled by an Arduino Uno,<\/div>\n
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Source code on GitHub.<\/a><\/div>\n
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