Author Topic: What's inside of a Harbor Freight 220V Spot Welder?  (Read 14597 times)

Offline vtsteam

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What's inside of a Harbor Freight 220V Spot Welder?
« on: June 12, 2025, 02:31:21 PM »
What's inside a Harbor Freight 240 volt spot welder? Well the switch on mine was starting to act flakey, so I decided to find out.....

   [attachment id=0 msg=165891]

End cap left, fixed handle lying on top of main body with switch wires and switch, moveable handle above that. Handle pin partly removed at front.
I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg

Offline vtsteam

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Re: What's inside of a Harbor Freight 220V Spot Welder?
« Reply #1 on: June 12, 2025, 02:51:46 PM »
End cap removed:

 [attachment id=6 msg=165892]

The cap and back end of transformer windings

 [attachment id=0 msg=165892]

The fixed handle and trigger wire running down channel to the switch:

 [attachment id=5 msg=165892]

Switch with ring of paper insulator

 [attachment id=4 msg=165892] 

Switch wiring

 [attachment id=2 msg=165892]

Switch construction

 [attachment id=1 msg=165892]

Switch contacts

 [attachment id=3 msg=165892]

I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg

Offline vtsteam

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Re: What's inside of a Harbor Freight 220V Spot Welder?
« Reply #2 on: June 12, 2025, 03:05:35 PM »
The front arms. Upper moveable arm removed. Sits in cast aluminum retainer, attaches to brass contact shell:

 [attachment id=1 msg=165893]

The handle pivot showing straight knurl for "press" fit (doesn't work well)

 [attachment id=0 msg=165893]

Upper arm contact (brass right) lower arm contact (copper center) and pivot

 [attachment id=2 msg=165893]

Upper and lower arm contacts (front view)

 [attachment id=3 msg=165893]


 [attachment id=4 msg=165893]

Lower contact, showing insulation at bottom

 [attachment id=5 msg=165893]
I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg