Replacement Nuts

cracked nut

Summary: Using 3D printing to fix things around the house.

Today I noticed one of the nuts was missing from our floor mop. Upon closer inspection it became apparent that the other nut was broken. I could easily have grabbed a pair nuts from my shop and used those as replacements, but where's the fun in that?

I quickly designed a replacement in 123D Design. I changed a few measurements to try and make the new nuts stronger. Then I printed out a pair on the UM2 at normal quality.

What do you know, they fit! There were a few design challenges. I tried to size the hole so the screws would cut threads into the nuts. The size of the screw hole was critical. Too small and the nut would crack. Too large and the threads wouldn't catch. I also added a chamfer at the bottom of the hole to make it easy to start. I guess I got it right because the screw is on nice and tight without cracking. I needed pliers to screw it on the first time, but after that I could do it by hand. I also needed to make the nut strong. I meant to print it solid but I forgot. But luckily it looks like the 20% infill was sufficient.

problem solved

The new nuts work perfectly. And as a bonus, the print lines give the nuts a no-slip texture! Maybe this wasn't the most practical solution but the blue plastic knobs look much nicer than a pair of steel hex nuts. And who wants to use a wrench on their mop anyway? I wonder what else needs fixing around the house?...

The files are available on YouMagine and Thingiverse.