Chain break tools are used to remove pins from bike,scooter, or motorcycle chains so that they can be resized.

I have seen several videos recently showing people making their own chain break tools. Each one required welding equipment and knowledge. I have neither, so I thought to myself, “I wonder if I can build a chain break tool that requires no welding?”

Challenge accepted. Here are the results.

Supplies

Materials Needed:

Mending plates (2 or 4, depending on thickness)
Bolts (3)
Lock nuts (2)
Jam nut (1)
Wing nuts (4)
Washer (1)
Epoxy

Tools:

Wrench
Bench Grinder

Step 1: Make a Push Pin

Thread a jam nut on a bolt. Put the bolt in your drill, head & nut first. While slowly rotating it in your drill, rub the end of the bolt against a spinning grinding stone until you reach the desired thickness. It should be smaller in diameter than the chain pins you will be removing.

Once you’ve reach the desired thickness, slowly back the jam nut off the bolt until it is removed. This will repair the threads where the ground-down part begins.

Finally, epoxy a washer on at the head of the completed push pin.

Step 2: Attach the Guide Nut

Using epoxy, attach a jam nut to one of the middle holes on a mending plate. Make sure it is centered, as this will be what guides the push pin. You can use a bolt to make sure it is lined up properly. Be careful not to get any epoxy in the threads of the nut. Let the epoxy fully cure before continuing.

Step 3: Assembly

Pictures do more than words. Assemble your tool as pictured.

Step 4: Start Breaking!

Align the chain pin directly under the push pin, so that it lines up with the chain pin you want to remove. Adjust the tool depth using the wing nuts as needed. Use a wrench to slowly drive the push pin until it has pushed the chain pin out enough to remove the roller link.

If you’ve never broken a chain before, here’s some advice: Don’t push the chain pin all the way out. You want to leave it attached to the outer link for proper reassembly.

Step 5: Conclusion

I built this for the fun of it and to see if it could be done.

It works, so I’m happy with it. However, my real chain tool works better, so this will be relegated to my junk pile until I need to scavenge the parts for another project.

Thanks for reading.