Re: servo or stepper size selection

I'm using Mach1 but haven't got round to mounting a ballscrew on Z
yet. I was thinking about using a 16" Hiwin Y screw they make for
the BP, but haven't got round to dissasembling the mill again to see
how much modification I would have to make. I'd be very interested
if you could send me any details of your conversion off list. Did you
have any problems with Z moving when power is removed? In an earlier
post I think it was Jon who thought there may be some problem without
either struts or some other restraint.

Bernard

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "motovidia <motovidia@a...>"
<motovidia@a...> wrote:

> Bernard,
> what type of software are you using for the nc controller?
> do you have ballscrews on the Z ?
> my bp clone with ballscrews on the Z and 40 in/lb servos can rapid
> at 150 ipm+
> > of torque. (My mill required 56lb/in, 784oz/in to start moving.)
> > Steppers have high torque at low speeds which drops off at the
> higher
> > speeds, servos on the other hand have very little low end torque
> and
> > require to move fast to bring it up, this is fine for X&Y.