Date: Sun, 09 Jun 1996 23:45:17 -0700
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: jwakefield@4dmg.net (john wakefield)
Subject: Removing broken bolts revisited
A few days ago I responded to a request for suggestions as to how to
remove broken bolts from a block. I described having heard and once seen
the process of using an electric arc welder to fuse a welding rod to the
broken end, and using the newly formed single piece to screw the
remaining bolt end out.
Well, I just had a chance to ask this expert and practicer of many
strange and unexpected tricks, just how it's done. I'll leave out the
references to pregnant female dogs, their offspring, and sexual acts, but
my lack of precision in this description is largely due to the fact that
my source understands, feels and acts in an artful way rather than as a
calculating engineer.
He covers the outside of the rod with something nonconductive, some
thin tubing or even tape will do. Then he selects some rod that's really
large for the hole. He selects an amp range using his AC welder that
will easily deliver some good "fire." Then he starts and briefly
maintains an arc, enough so there's no doubt that he has two molten ends.
Next he "sticks" them together, and instantly releases the rod from the
rod holder by depressing the spring loaded holding clamp. Then, he bends
the rod 90 degrees compared to the part that's stuck. "Now, you have to
wait for a bit, so the heat will work its way down into the part and
disturb the frozen surfaces. Then you just turn it out using the bent
part of the rod as a handle." He's done it a lot in the last 40 years,
and he says those 5.7 liter GM diesels needed it a lot. He also reports
that it seems to work better on stuff that's not too small.
Well, that's it folks. I tried to pump for more specific measurable
descriptors, but that's just not the way he does things. Hope this adds
something usable to a stuck persons arsenal. Lots of us have struggled
with "easy outs," and the success rate is reported to be better for this
technique. Failure will leave the familiar artful drilling etc.
Good luck,
John
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