Cutting ballscrews to length the easy way?

[routercnc]

My second machine did not have a machined floating end on the X axis ballscrews and I had some 16mm ID bearings that were a perfect fit so used those. The machine ran well for many years and both mk3 and the current machine are like that. So it can be done and works ok but you wouldn’t see it on a commercial machine.

On the unsupported end question all my machines had supports even on Z but I couldn’t fit them on mk4 as they ran inside the side members of the Z axis. It works fine and I think up to 300 mm is OK unsupported. After that you need to think about the free end starting to whip at high speed.

Not many machines (DIY) have double support but it should help with longer screws rotating at higher speeds. My mk4 effectively has something similar on the X axis to give tension.

[magicniner]

On my Chester conversion I though there may be a chance of whip at higher speeds for the X axis so I have mounted the screw between bearings in tension. Y is too short to worry about but I might do the same for Z as that's also quite long.