Broken tap

[Ron Nossaman]

Hi Andrew,

Ouch! Why was he tapping out the plate hole, and to what size? I haven't had
to do this often enough, fortunately, to get good at it, but here's what I'd
try. Put a few drops of penetrating oil in the hole to try to slick up the
threads as much as possible. If you ever do get the thing to move, you want
to encourage it to do so. Then, take a small pin punch and tap lightly on
the top of the tap. The hole should go all the way through the plate
(hopehopehope), so do the same from underneath. Alternate between top and
bottom a half dozen times. Don't pound on it, just a (pardon) tap. You're
trying to loosen the jammed chips so the oil can get to all the surfaces.
Then try your (re made) double rod tool again. Jiggling and coaxing, back
and forth, a little at a time, is the thing here, not forcing. If that
doesn't work, and the top of the tap is accessible, use one of those little
Dremel cutoff wheels to cut a small screwdriver slot in the tap and try
again with a little more oil. Patience. Sometimes being more hard headed
than the problem pays off. If nothing else works, a small hole saw (no
bigger than necessary,just big enough to clear the tap, and without the
pilot), will take out the whole mess. Thread the hole for an insert. Make a
brass insert, 1/4" x 36 internal thread for the new agraffe, and
appropriately sized and threaded to fit the plate hole. Install the insert
with a little JB Weld and, when it's cured, install an agraffe. This can be
done without leaving any visible indication of the repair if you can get, or
make, a hole saw small enough that the outside diameter fits inside the
diameter of the spot faced agraffe landing on the plate. The new agraffe
will cover the whole thing. This qualifies as heroic measure, and you have
every right to price it accordingly. 

Anyway, that's how I would approach it.

PS: Sorry to hear of the recent death of your titanium bit.

Much luck,
 Ron