Originally Posted by
Moose
Theres a tool for auto mechanics used for disassembling ball joints, affectionately called a pickle fork by some. It's a two prong fork with wedge shaped tines that slip between the crank and the bottom bracket. You insert it and whack away at it with a hammer. Brutal and marginally effective, but I have seen it work.
There's another, and better tool for auto mechanics that I used (on a non-drive side mind you) crank arm the other day that came into the shop with no threads and needed a BB repack:
What you need is a pulley-puller:
Be sure to put an old crank bolt in the threaded hole on the BB to press against so you don't wreck the threads in the BB (and leave it a bit loose so the arm can acually move!)