Re: [CAD_CAM_EDM_DRO] build an edm

My copy is only 56 pages - less than half of the quoted 125 pages. The 56
pages cover in good detail all the items needed for the EDM. He is using a
unipolar stepper to control the electrode. I've seen other designs use
servos and let the gap voltage control the servo. My design is using a
linear actuator - everyone will have their personal preference.

The PS in the book is built from scratch with lots of caps - I would just
pick up some surplus supplies from www.mpja.com and save the time and
hassle. I think he's cutting at 80 or 90 volts - so just buy two 48V
supplies and put them in series and you'll be covered for under $100. Then
you can concentrate on the controls.

I've found that the higher the voltage, the more tolerant the cutting is -
less arcing and shorting. Of course, if you have the process automated, it
won't much matter - the electronics takes good care of controlling the gap
and shutting off the supply when needed.

The book is very complete and provides everything you need (although I
remember hearing people saying that some of the follow up [re: Part 6] had
some component values missing - you should be able to back into these)
including nice hand drawn sketches of how to solder and where pin 1 is on a
chip!. You could certainly follow along and end up with a usable piece of
equipment.

HTH,

James

----- Original Message -----
From: <davemucha@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Thursday, December 12, 2002 7:40 PM
Subject: [CAD_CAM_EDM_DRO] build an edm


> Hi,
>
> does anybody have the book
>
> Build an EDM by Robert Langlois ?
>
> I found different descriptions and it seems the 'newest' version has
> 125 pages.
>
> I am interested in how complete the book is and how well it covers
> power supplies.
>
> any additional information anyone wants to offer is more than welcome.
>
> Dave