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

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 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).

John Kasunich