> The trick is to drill as big a hole as you can get away with which means
> you have to be very careful to start you r first hole in the center of the
> bolt. This can be quite tricky especially if the bolt broke off leaving a
The other trick is to centerpunch the end of the bolt (give it a good
whack), in order to ensure that your drill doesn't wander. Then, start a
hole with a relatively small diameter drill. Just drill deep enough to
establish a hole. Then, change to a larger diameter LEFT HAND bit and drill
the bolt out, with your drill in reverse, of course. The drill diameter
should be a little smaller that the minor diameter of the thread. The
reason for using a LH drill is that the vibration and stress will sometimes
break the bolt loose and it will start to turn out of the hole as you drill.
If you use a bolt extractor, I have had the best results with one that has a
relatively "slow" thread, that really bites into the bolt.
And if this note makes anybody mad, let me apologise right now so we don't
waste the bandwidth! :)
Michael Marr
Naperville, IL
1960 TR3A
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