Uploaded May 2019 | Updated September 2026, 11 hours ago
Finally, a working spot welder! This DIY project has taken a long time to work the bugs out, but here it is. I'm using a contactor for 240 volt appliances. Also a 12 volt battery that I made in a previous video, a timer, tungsten tips. and a microwave transformer.
In this final video about the spot welder I go back to using 120 volt power instead of the 240 volts. I also exchange the SSR for a contactor (relay). This 30 amp contactor is usually found in large appliances like furnaces and air conditioners.
I work through timing to get the best weld on the batteries without over-heating them. I found the negative tab (copper) worked well with one long pulse at 0.65 seconds. The positive tab (aluminum) worked with a double pulse, each 0.35 seconds long.
Timer Board: amzn.to/2L7nPqm
Contactor: amzn.to/2Ecd2FD
Thanks for watching. If you would like to help support the channel please check out Patreon, or use an affiliate link. Thank you.
patreon.com/DavidPoz
We can chat and share project pictures on facebook: facebook.com/DavidPozEnergy
“As an Amazon Associate I earn from qualifying purchases.”
Finally, a working spot welder! This DIY project has taken a long time to work the bugs out, but here it is. I'm using a contactor for 240 volt appliances. Also a 12 volt battery that I made in a previous video, a timer, tungsten tips. and a microwave transformer.
In this final video about the spot welder I go back to using 120 volt power instead of the 240 volts. I also exchange the SSR for a contactor (relay). This 30 amp contactor is usually found in large appliances like furnaces and air conditioners.
I work through timing to get the best weld on the batteries without over-heating them. I found the negative tab (copper) worked well with one long pulse at 0.65 seconds. The positive tab (aluminum) worked with a double pulse, each 0.35 seconds long.
Timer Board: amzn.to/2L7nPqm
Contactor: amzn.to/2Ecd2FD
Thanks for watching. If you would like to help support the channel please check out Patreon, or use an affiliate link. Thank you.
patreon.com/DavidPoz
We can chat and share project pictures on facebook: facebook.com/DavidPozEnergy
“As an Amazon Associate I earn from qualifying purchases.”
