RE: [CAD_CAM_EDM_DRO] Re: stepper-servo system

HI Graham,

Sounds like an interesting project! And it's funny how different bits of
technology come back around to be re-used!

Thanks for the comments.

Alan KM6VV

> Subject: [CAD_CAM_EDM_DRO] Re: stepper-servo system
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Alan Marconett" <KM6VV@...>
> wrote:
> >
> > Do you know if measuring the spark voltage on EDM would tell one
> something
> > about its length? Is this info then used to control the advancement
> of the > electrode?
> >
> > Probably some sort of simple positional only servo loop?
> >
>
> yes yes and yes. If there is no sparking you see the open circuit
> voltage modified by the duty cycle, if sparking occurs the average
> voltage drops, if it drops too far you are in to arcing and you need
> to back up, if the voltage is too large you are too far away and you
> need to move downwards. There is lots to it if you want to get
> optimum performance but very simple methods do work in practice, I
> want to do one better than very simple.
>
> A stand alone machine with GUI, mouse and keyboard is going to be
> pretty sweet if I can get it working. Then apply what I have learnt
> to the wire machine.
>
> Graham
>