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

On Wed, Nov 06, 2002 at 07:40:29PM -0000, jmkasunich wrote:

> Jon Elson wrote:
>
> > Yes, all the tap burning I've done has been manual.
> > The CNC system actually did the moving, but I was there
> > the whole time, pushing the jog buttons, mostly.
> > Without the flushing of chips, I had to stop and back
> > up very often. If you can rig some brass tubing
> > and use an elevated can of EDM fluid, you may have
> > much better results.
> >
> > I am going to do this the next time a tap needs to be
> > burned out.
> >
> > As for really fine feeds, leaning on the machine
> > may do it! I actually modulated the
> > arc by leaning on the head of my Bridgeport mill!
> >
> > Jon
>
> 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.

I have a simple, commercial, EDM tap zapper. It has a vibrating
head that mounts in the chuck of a drill press or mill. There is
a fluid pump to run EDM fluid through a hollow brass electrode to
flush out the crud generated during the process. I have used it
a couple of times and the head does NOT rotate. You just hand feed
it down just fast enough to maintain the arc. The vibrating head
is the important part since it speeds up the process enormously.
Rotating the electrode would probably serve the same function at
the spark gap, but then it gets hard to pump fluid though it.

> 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).

You ought to be able to go buy a gallon of DI water at your local
supermarket for a buck.

Paul

--
Paul Amaranth, GCIH | Rochester MI, USA
Aurora Group, Inc. | Security, Systems & Software
paul@... | Unix & Windows