Need EDM / Tap removal - Los Angeles

Oyyy Yoyyyy!

Are the taps HSS or carbon steel, do you know?

Carbon steel taps can often be removed with a burr in a Dremel or similar tool, after heating the part to near a red heat and allowing it to cool slowly.

I've carved out a HSS tap or two using dental burrs, but its slow work.

I'm sure there must be a shop around with a tap burner. I'd start by calling machine shops in your area to see if they can either help, or recomend someone.

Meanwhile, time to start working on a tapping guide. :-)

Cheers Trevor Jones

Tap Ex

1940 W Rosecrans Gardena, CA 310-323-3834

The area code may not be correct, been years since I used them.

I built a little EDM tap burner myself for similar crises. See

for how I did it. If you have some electrical/electronic junk around, this could work quite well. The smaller the tap, the faster it will burn out.

Jon

Yes, he's still there and willing to do the job. He says he is going to retire but has a little too much work right now and so he will wait a little! Glad to see he has a specialized little machine. Most of the suggestions on technique won't work with this tiny little carbon steel tap (0.096 major diameter).

-- - - - - - - - - - - - - - - - - Bill Graves RKBA! snipped-for-privacy@ix.netcom.com

Bill, He's been saying that for 15 years now - almost exactly that same line. The biz is in his blood I think, he won't retire - he will die ( and happy at that).

Another tap extractor is in Downey. Orange Engineering 562 803-1106

Tap Ex

1940 W Rosecrans Gardena, CA 310-323-3834 John R. Carroll

Yes, he's still there and willing to do the job. He says he is going to retire but has a little too much work right now and so he will wait a little! Glad to see he has a specialized little machine. Most of the suggestions on technique won't work with this tiny little carbon steel tap (0.096 major diameter). I built a little EDM tap burner myself for similar crises. See

for how I did it. If you have some electrical/electronic junk around, this could work quite well. The smaller the tap, the faster it will burn out.

Jon

Neat idea, Jon, I may try it.

I have a friend who has an EDM shop (San Jose area), but I hate to admit I was an idiot and broke the tap...

It occurs to me that it might be easier to connect the electrode lead to the mill and insulate the work in the vise. Obviously, one would rather not have arcin' & sparkin' inside the mill quill, but a commutator to the drill chuck shouldn't be too hard to rig...

Jerry

If it's an aluminum casting, there was a recent thread here (r.c.m) on boiling in an alum solution to dissolve the tap.

Ken Grunke

IIRC, nitric acid dissolves steel taps while leaving Al stock alone. I've not tried it, but I think I read it in one of the Machinist's Bedside Readers.

LLoyd