Introduction: Machining Replacement Tips for Harbor Freight Spot Welder
The contact points of our Harbor Freight spot welder had gotten too pitted and damaged to work. I had no luck getting replacement parts from anywhere, so I made a replacement set. I used TechShop San Jose's lathe to make the parts.
Step 1: Load Copper Rod Into Lathe With Collet Closer
I bought a nice copper rod from McMaster-Carr - it wasn't cheap, but it was less costly than a new spot welder. The piece was 3/4" in diameter, so I used a 3/4" collet to hold the rod.
Step 2: Cut Thread Side to 8mm
The threaded part of the tongs that the tips screw into are 8mm, so the plan is to cut the copper shaft to 8mm.
Step 3: Cut Angled Tip
Using a triangular cutter, I shaped the front of the part to resemble the bad one I had taken off.
There is no need to part the piece, as it will pop off when you get mostly done shaping.
Step 4: Thread the Back Side
I used a die to thread the back side. Shiny!
Step 5: All Done!
Install the tips and weld! The originals had flats to use a wrench to install them, but a pair of pliers or vice grips works fine.
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8 Comments
2 years ago
supposedly, Miller tips will work as well.
6 years ago on Introduction
I found replacement parts by calling Harbor Freight. Here's the info
The part you are requesting can be ordered by contacting our Inbound Sales department at 1-800-423-2567. They are available 24 hours a day 7 days a week.
SKU# Part# Description Price (plus tax & shipping)
15551 24 61205/61206 ELECTRODE TIP 2PK $15.99
7 years ago on Introduction
This is a great project and you obviously put a lot of thought and craftsmanship into it. FYI AK-builder.com does sell new tips for the HF spot welder. Good job though!!!
8 years ago on Step 5
you can file a pair of flats on the tip to use a wrench if you want.
8 years ago on Introduction
I'm curious. Do you buy taps individually, where and when you need them for specific tasks? Or did you buy a complete set of them up front? Or do you find there are a few key sizes that are your go-to's that cover most of your needs? If yes to the latter, which are your most frequently used taps?
Reply 8 years ago on Introduction
I have usually invested in full sets of taps over the years - a nice combo metric & SAE set has kept me company for about a decade now. Craftsman brand, as I recall.
However, for this project, I was able to use the ones at TechShop San Jose to do the job -- they have a complete set available for member use.
8 years ago on Introduction
Great job!
8 years ago on Introduction
Great job!