Re: update copylathe with Siemens 802c and Newall Microsyn readout

From: "Sven Peter, TAD S.A." <peteryco@...>

>I plan to convert my hydraulic copy lathe ...
>Can anybody give me a tip for to get appopiate proportonal
>4 way valves? (Presure 20bar, Flow max 5liter per minute)

The cylinders work okay to copy because they form a kind of rigid link
between the pattern and the cutter. But there is nothing like that kind
of control when you replace the pattern follower with a flow control valve
and a computer.

I serviced hydrapoint and sheldon hydraulic machines for several years and
have the impression that it is very difficult to get the kind of control
of hydraulic flow that works well in these kinds of machines. I've
watched some installers put the latest versions of electronic flow
control valves in several lumber mills around and these things are a
real b**** to tune and require frequent resetting to maintain the 1/32
accuracy that the mills use.

I'd replace the hydraulics with some other kind of drive.
--

Ray