Just starting out with the calculations to see if this concept will actually work in practice.
Its mainly going to be for machining Delrin and Aluminium, the spindle is a 1/2 HP affair that I hope to be able to run at about 2500 RPM (the belt drive conversion lets you go up to 4000 RPM but will probably have very little torque up there)
Work Area: X=320mm Y=150mm Z=200mm
Weight: works out at around 70kg excluding the servos (since i haven't got hold of them yet)
the X and Z axis works out at 24kg in moving parts
The linear Rails I have lying around are THK HSR20 (overkill I know but thats ebay for you) and the ballscrews I have around are 20mm Dia 5mm pitch C7 grade with a double ballnut (not the ground ones I originally thought of using but I just looked at the prices of those things new ) again probably overkill but they are sat doing nothing.
Also just had a small panic attack about the rigidity of the Z axis at its lowest point, 200mm of free floating rail and aluminium jig plate with a whacking great spindle on the end .