Jeff, I have never tried it, but have been told that nitric acid will eat
that right out of there. Probably your best shot is to take it to your
local machine shop and pay them $10 to do it for you. They will either have
the nitric or the right jigs and bits to remove it. (I am currently going
through the same thing on a front brake caliper bleed screw.
Patrick Bowen
-----Original Message-----
From: Jeff McNeal [mailto:jmcneal@ohms.com]
Sent: Sunday, March 05, 2000 11:50 PM
To: Spitfire List
Subject: screwed...
Pardon the abrasive header of this message, but it seems like the most
concise way to describe my situation. When replacing my seat rails
yesterday, I noticed that the PO had drilled an alternate hole in the seat
track because he busted one of the 1/4" mounting bolts in the original hole.
Up for the challenge, I sawed off the nub sticking up so I would have a
nice, flat surface to drill through, which I did with a 7/32" bit, drilling
through the old bolt. So far, so good.
Next, I borrowed a buddies tap and die set and proceeded to tap a new 1/4" x
28 thread. Then, SNAP! The tap busted off inside the hole, with no way to
get it out. I killed two perfectly good drill bits trying. Someone
suggested a cobalt drill bit to slice through the hardened steel of the tap.
Now, the thing is a real mess and I'm trying to figure out the best way to
drill back through and retry with a new tap.
I wish there were some kind of jig I could create that gave me the stability
and precision of a drill press. Right now, there's no way I can get the bit
started straight on because of the way the tap broke off. My plan at the
moment is to attack the problem from the bottom side this time, using a die
grinder to flatten off the bottom, before drilling up and through. Before I
attempt this, is the broken tap going to be too much for my grinding wheel?
IS there a simple, clever way to rig up a portable drill press so I can
drill straight down without worring about drilling crooked? Or should I
just say "screw it" and use the alternate hole that the PO drilled, even
though it interferes with the travel of the sliders?
Thanks!
Jeff in San Diego
67 RHD Spitfire Mk3 aka Mrs. Jones
www.ohms.com/spitfire/spitfire.shtml
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