Re: [CAD_CAM_EDM_DRO] Another EDM Approach

----- Original Message -----
From: "Jon Elson" <elson@...>
>
> > When the circuit was working, it did a
> > fairly good job of tap removal etc. but just wasn't refined enough to do
any
> > really useful work.
>
> This mUst be EXTREMELY slow. The pulsed EDM systems run 10,000 sparks
> a second and more! backing up the electrode after every spark must take
> hours to make even a thousandth of an inch progress.

Hi Jon,

It was, in fact, fairly quick and would go through 1/8" steel sheet in about
10 minutes. I suppose that what you actually get is a stream of sparks not
just one as the electrode is slowly lifted by the motor. i.e. there will be
a significant time interval where the electrode/work distance will support a
spark current flow. The big trouble is, of course, that it is uncontrolled
and each spark will start off very strong and progressively weaken before it
dies. Also such a system is slow because each time the motor lifts and
lowers the electrode, backlash will have to be overcome. A system which
monitors current and just maintains a fixed gap must be far more efficient.

Ian
--
Ian W. Wright
Sheffield UK
www.iw63.freeserve.co.uk