Let's Make Robots!

Wild Thumper steel wire repair

Byrik

While disassembling my Wild Thumper (for unrelated reasons), I discovered one of the steel wire suspension limiters had detached. So I decided to repair it with whatever I had in the house. Which happens to be copper wire and soldering tools.

Here's the problem:

The wire is looped and the two ends were held together with some sort of soft metal crimper. And that crimper has come loose. So I figured I could make my own crimper. Out of the soft metals I have on stock: Cu, Sn and Pb.

Make my soldering iron a bit hotter than usual and soak the shit out of the copper.

Clean it up a bit for the "final" photo.

Notice that the steel does not adhere to the solder. For extra grip, I crimped the wrapper with flat nose pliers. That's a 7.5 mm resistor for scale. Total length of the cable turned out to be less than original. So I attached it to another screw hole in the motor house, to compensate.

I put everything back together and jiggled the assembly a bit to test out how sturdy my repair is. Well..... as it turns out: sturdier than the original!

I just hope I've got sufficient length of steel left to repeat my trick. Or I'll have to find a local supplier of thin bicycle braking cable.

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OddBot's picture

Yours is the first I know off that has broken but working on the assumtion that others will do so in the future we are now looking at changing the crimp material as I think the aluminium is too soft.

Your homemade job should work well if it is crimped hard enough. If any more break then let me know and I'll send you a new set.

rik's picture

You just make sure to check the usual location for videos.

OddBot's picture

Yes I did. It reminded me of Turbo Trike hitting my camera and scratching the lens.

It also made me relise that you could make the ground clearance of the Wild thumper controlled by your processor. Attach a second cable to the center of the suspension cable with the other end connected to a powerfull servo. When the servo pulls at the center of the suspension cable it will pull the wheels up causing the chassis to squat lower.