Plenty of interest then.

Defining mid range could be a problem. linear rails, ballscrews and vfd spindle seems quite high spec to me....

theres enough flexibility for people to use what ever they need to suit their requirements. Although I dont think it wouldnt be very economical to mount a dremel on a machine designed to take a heavy vfd spindle?

Thanks Irving. thats perfect, knew I'd seen that somewhere. Is that the rotational force of the motor or the force required to push the axis?

If high speed is needed then would it be better to use belt drive? or would that cause problems with higher powered motors?

For the drivers has any one else seen the "CPLD tutorial" on cnc zone? from memory :whistling:

80V @ 7A with 5 micro steps and works out at £10 to 15 an axis. The only drawback is the chip is a tiny SMD so not very diy friendly. It was proposed to mount a preprogramed chip on a separate daugther board that could plug in to a 40 pin wide DIL and be sold cheaply so people could then build their own but it was never realised. any takers?