Re: Counterweighting the Z axis ?; Power off position holding ?

Hi Kim, I am in the middle of retrofitting a ZAY7045L square column
mill/drill. Are you converting the Z to ball screw for better
accuracy, reduced friction, or to get rid of backlash? I would say the
best thing to do if you want to go to a ball screw is use an electric
brake on the motor. The simplest solution is of course to use the
original acme lead screw. There is no way that will move when power is
removed. Do you think backlash will be a problem even under the weight
of the head?
Dean

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Kim Lux <lux@d...> wrote:
> Glad to hear I am not the only one.
>
> The problem with springs is that their force varies with where the head
> is. Maybe they could be adjusted for zero force in the home position.
> That wouldn't help for an EStop though.
>
> A regulated air cylinder could give a constant force with any position,
> but I'm worried the air dynamics would mess up the head motion.
>
> So far the best solution seems to be to counter weight it and/or apply a
> bit of drag to the ballscrew drive.
>
> Kim
>
> On Tue, 2003-07-08 at 08:46, tsalaff wrote:
> > Kim,
> >
> > I'm dealing with the same problem right now although my Z axis is only
> > 40 lb.. Going to try making brackets to anchor support springs. Will
> > report on how these work.
> >
> > > motor the milling head will slide down the column as soon as
power is
> > > removed from the servo.
> > >
> >
> > > Kim Lux <lux@d...>
> >
> >
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