Re: EDM troubles - update

Hi all,

a week or so ago I ran into the problem that by pulling the electrode
out of the part (dinner time and I didn't want to leave it
unattended) that I could not resume sparking.

This happened a few times. I tried to wire brush the copper, use
scand paper, all to no avail.

on a bearing race, I pulled the bearing out and found that in the
bottom of the cut was a fluffy substance, similar to the stuff at the
bottom of my water tank.

evidently, by stopping the cut and waiting for some time, the stuffs
in the water will settle and for some reason that stuff is not
conductive so does not spark.

a little compressed air and presto! now I gotta paint the ceiling.

now, I can look forward to answering the new-age question of which
happens faster, edm work or paint drying......

Dave






--- In CAD_CAM_EDM_DRO@yahoogroups.com, "turbulatordude"
<davemucha@j...> wrote:

> 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)