[Shotimes] Bolt Extractor Kits

[BJamesjr@aol.com]

>I and several others on this have never had any good luck with bolt
>extractors.  They simply break off in the broken bolt and make that much
>harder to drill out.

This can certainly be a problem.  If a bolt is tight enough to break off, 
then don't expect the piece left in the hole to be easy to get out.  However 
the extractors do work a good percentage of the time.

>Some one suggested a left hand drill bit, which makes much more sense.

Some of the extractors actually look like this, i.e. they have tapered 
spirals going opposite of a drill bit.  As you try to back out the bolt the 
extractor gets tighter in the hole.

>In the worst case you will have to re-tap the hole and use the next larger
>size bolt.

If you are real careful and use the right size bit, you can drill a perfectly 
concentric hole that leaves only the threads themselves in the hole.  Then 
these come out pretty easily.  Very difficult to do in the car however.  
Easier if you can pull say an exhaust manifold off and clamp it in a vise.  
Say you have an 8mm fastener, the right size drill bit would be the one that 
would slip easily through the appropriate size of nut for this 8mm fastener.  
I've seen a lot of bolts drilled out but never one that had to go to the next 
larger size.