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A tool that can be used to tighten nuts on a long bolt/rod where a socket will not reach, but with the ability to be driven by a drill or a handle.
I have designed this to help put nuts on a long threaded rod for wind turbines with the aide of a drill so that it does not take an absolute age to do.

I've added a handle which could be held between 2 tightened nuts on the bolt instead of using a drill to drive it.

It looks a little basic / utilitarian, but should be able to get the job done.

I have made it so it can take attachments from M4 to M12 sized ISO nuts.

It requires:
- 5 small screws (approx 3.0x10 - Cap head preferable but not necessary)
- 1 M8 skateboard bearing
- 1 or 2 M8 Nuts (4 if using the handle)
- 1 M8 Coach bolt, with a minimum length of 50mm,but long may be better
- A little grease to be applied to the top and bottom rings of the Large gear and on the gear teeth to give a smoother mesh

As for print settings, my only advise would be to have a high i