Machining Replacement Tips for Harbor Freight Spot Welder




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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    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 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.