Bolt extractors

[junior varsity]

no no, i mean for the extractor to bite into, sometimes the existing allen's hole will work. Other times its not really able to provide enough grip - its not deep enough.  The craftsman extractors require you to drill into the bolt a bit, but on some harder steel, it just makes a really nice smooth polished hole in the bolt, but doesn't penetrate so much. For that, you can help it along by drilling a small pilot in the center of the stuck bolt. Then it works quite well.

i had some damn brake rotor bolts stuck this way and the damn things wouldn't come out despite my best intentions. Tried oil+sand on the end of the allens, tried torx bit hammered in, heat + penetrating oil, all to no avail. Went with extractors next since I didn't have any welding equipment (would just weld in an appropriately sized allen if I had it), and they take some doing, but seem to work well. One ate the dust on me though.

[LowThudd]

The blind man says "ah, I see".