Re: [CAD_CAM_EDM_DRO] Re: Tap burning EDM? Need it Quick and Dirty ;-)

jmkasunich wrote:

>This is encouraging. I think I have some 1/16 OD brass
>tubing and some aquarium air hose.... How important
>is it to rotate the tool - I don't think an elevated
>can of fluid is compatible with a rotating tool, not if
>I'm trying to cobble things together quickly.
>
>

No, the rotation was my best attempt to keep the chips from piling up in one
spot and shorting out the electrode. Most sinker EDMs don't rotate
their tools.

>I like the idea of feed by flexing the machine head.
>The Shoptask mill is a _lot_ more flexible than your
>Bridgeport! I can feed by pushing the head down until
>it gets hard to do, then release the pressure (sparking
>will stop) and crank in a few thou with the feed until
>sparking starts again. Then feed by flex for another
>few thousandths.
>
>Any suggestions for fluid? Like you, I don't have any
>source for DI water. I don't have any "Alum-Tap", but
>I might have some Tap Magic. I do have WD-40 (mostly
>kerosene, which some people have used - fire risk?),
>and heavy gear oil (I use as cutting oil).
>
>

Alum-tap IS flammable, too. A little less volatile than paint thinner,
but otherwise
a very light oil, or a 'heavy' solvent. I did have one flash with the
stuff, when the
level of it was sputtered away and a big spark shot out. It was just
one little orange
flash. As long as the work area is covered by a few mm of fluid, the
hot sparks
can't get out to the air. Still, I wouldn't want to have lots of
flammable fluid
around. I usually had about 2 cc's here and there when I was EDM'ing,
so I wasn't
too worried about a large fire.

I think you want something very light. People tell me deionized or
distilled water
is real good. It is cheap enough to use once-through.

Jon