King Midas mill conversion

[diy-john]

You are all doing a good job explaining the principles.
- It was me who assumed X and Y -axis ballscrews are put together in similar way.
- Assumed too, that idea is to make it as sturdy/rigid as possible.
- There are some gaps in my knowledge, filling the gaps with assumptions doesn't always work

But it will be good. Will create another drawing of the ballscrews -setup.

Thanks again for comments!

[Robin Hewitt]

... and only one pair of Belleville washers, you don't want to balance the screw between two springs because that can move.

A few design tips.

I bolted the X screw pulley solid to the inner race. I sprung the sleeve that takes the handle at the other end. This reduced the bearing overhang I couldn't avoid on the Y.

Putting the handle on a sleeve means I can pop the handle off without detensioning the screw. Handy if I want to work on something that overhangs the end of the bed.

I mounted the X motor facing the unlikely way round and extended the screw to get clearance on it. This makes it a lot easier to mount, easier to change the belt and easy to pop a cover over to keep the crut and fingers out.

My X motor mount isn't actually bolted to the machine, it's free to turn. I was going to Loctite it in place but found the 500 lbf screw tension quite sufficient to hold it. I lean on it occasionally, if it ever moves I will know I have lost tension.