Re: [CAD_CAM_EDM_DRO] Langlois's HSM EDM m/c question

"Ian Wright" <Ian@...> wrote:

> Is this article part of the original series or is it a later follow-up. If
> the latter I have missed it - what extra benefit does it give?

It was in part 6 of the original series, which consisted of
outlines of extra bits of circuitry you might want to use - it included
a circuit diagram, but no component values. One bit was limiter ciruitry -
so it would stop when a microswitch indicated the end stop had been reached.
The other was a big transistor either side of the discharge capacitors,
so you could alternately charge and dischage them, with variable frequency
and duty cycle. This also means that the spark rate wasn't tied to 50/60 Hz.
The article hinted that this gave better quality finish if you wanted to
do something more than just burn out old studs. It also implied that
the discharge capacitors could be made a lot smaller.

Like the orignal poster, I'd be very interested to hear if anyone has
built this 'advanced' model, what final circuit details they used,
and what results were achieved.

Dave M.

PS - a big hello from Sheffield :-)