King Midas mill conversion

[Robin Hewitt]

Yes Robin, back to drawing board it is.

Wow! If you are okay to take advice you can make one hell of a machine. I got it right on my third set of screws when the penny finally dropped.

Problem is, you need a CNC mill to make a pretty CNC mill which is why I was suggesting you cobble something together first. Hope you have a lathe, really do need a lathe.

I used pairs of Belleville washers to apply a preload of 500 lbf. One pair for each screw to hold the axial bearings in tension, one pair for each double ball nut.

That means there is no play in the system, apart from the column bending, so long as the load does not exceed 500 lbf. It was a lot of work but is quite delightful to use and all self adjusting.

The XY screws appeared much too long until it was all together, have a pic...