[GalaticDan]

Hi,

Had this idea the other night about making the main spindle motor not move up and down with the z-axis but remain stationary like a drill or mill press. I thought after looking through a few mag's on slides why not use a meat looking rotatry ball spline. The spline would give the linear up and down motion for the tool head with the motor driving the bearing via a thick tube on the outside diameter of the bearing and then have the rail which is round connect to the tool chuck. I think it would work but does anyone know if it would hold up against the spindle torque required for milling?

Actually you probably need more information like "milling what material?" but just for now is the idea sound or way off?

I've not looked inside a drill or mill press to see how they create a telescopic drive head.

Thanks 4 reading,

GalaticDan

[ESjaavik]

Hi Dan,

I think you need to explain that better.
My mill have splines, but no balls. But it has big balls when it comes to milling any material. Phhhewww... I'm no better at explaining it seems....

What I should say is it has a spline coupling between the spindle and the driving cogwheel. One important point is that the driving wheel has it's own bearings so it don't impose any forces on the spindle except the rotational force.