Re: [CAD_CAM_EDM_DRO] Re: Re: replacing feed screw with a hydraulic cylinder

Marv Frankel wrote:

>Guys,
> I've been following this thread, and although I've never done it, I
>wonder if the coefficient of expansion of the hydraulic fluid, would cause
>some accuracy problems? On a cold day, it would cut differently than on a
>warm day, and would you have to reset your Z axis every time the temperature
>changed?
>
>

This was a closed-loop servo system, although pretty crude by today's
standards.
So, no, the coordinates didn't need to be reset. It might have some
variation in
feedrates or responsiveness. The fluid is kept plenty warm by the
hydraulic power
unit, so ambinet temperature won't have much effect. But, it may need
to be exercized
for some time from a cold startup.

I thought about making a hydraulic machine a long tima ago, and am VERY
glad now
that it was only a bad idea to contemplate!

Jon