Quote Originally Posted by Blackrat View Post
+1 clive ... i hear ya ... but then you go down the whole road of tuning fork ... and defeat the whole purpose of having the rails move

im going with bearings moving , like i drew on the original concept, its much easier and i doubt there will be any loss by going with this
This is ok if your only ever going to use long tools that reach the bed or material base but what happens if you want to use short stubby cutter.?

In this case if you have to drop the spindle in the clamp this then gives you a long fixed length lever that is a long tuning fork.!! That never changes it pitch no matter if you raise the Z axis.
This does make a differance and in some materials you will clearly see it compared to having rails moving. You can certainly forget cutting aluminium and expect any kind of decent finish.!!