Re: [CAD_CAM_EDM_DRO] EDM troubles

Dave,
One of a few trhings has gone wrong, try these things to find out what.
Get the electrode back into open air and see if the voltage is still there.

If so, then something has become non-conductive.
The tool (electrode) or the hole may not be conducting
or something else happened when you restarted,
like the voltage didnt come up, the cap blew or the gap got too small.

While the tool is up in the air, hook an alligator clip to it ( make sure
the power level
is fairly small ) drag the other end over the work surface, it should spark.
If it does then try touching the free end near the hole.. still spark.
Then maybe down inside? I know you cant see down in there but I'm
suggesting the thought process. Try cleaning the hole with a hard pointy
stick
( scriber or drill bit ). Hold the pointy thing in the hole so it contacts
bottom
and touch the free end of wire to it. Got Spark? If so then the return
to the cut was the problem, maybe just gets too close. Manually feed into
the
hole slowly ( or if power small, go ahead bump bottom and back off till
Voltmeter rises indicating gap open ) If you can spark then, it's a servo
(gap following) problem.
regards
tomp

----- Original Message -----
From: turbulatordude <davemucha@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Sunday, August 10, 2003 6:28 PM
Subject: [CAD_CAM_EDM_DRO] EDM troubles


> Hi all,
>
> simple RC EDM unit. after test drilling some holes in steel with a
> copper electrode, I pulled the electrode out mid spark to inspect the
> progress and now it does not start to spark easily.
>
> It went from full voltage to sparking voltage without a spark, then
> quickly went to a short.
>
> do the electrodes get dirty with carbon ?
>
> any suggestions ?
>
> Sparkless in New Jersey. (Dave)
>
>
>
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