Here’s the problem - the crankset is frozen onto the bottom bracket shaft.
I stripped the thread out of the crankset when I first tried removing it with my crankset removal tool. Then I doused the frozen bits of the crankset and bottom bracket with oil. Then I pulled, pushed, levered and bashed (with a large rubber mallet) the crankset while it was in the frame. Then I took the bottom bracket and crankset out of the frame in the hope of persuading someone with a chunky gear puller to try to remove it for me.
I seem to recall reading somewhere that a frozen bottom bracket will simply fall out if you heat it with a butane torch. However, I think that should only bind it even more firmly.
If I can’t get a gear puller, or if a gear puller doesn’t work, then the next step is to carefully cut the crankset off the bottom bracket with a hacksaw.
If you care little for the cranks, as I too cared little for some crappy old shimano cranks once, cut into the crank with an angle grinder in as many places as you can, so that you end up making the crank weaker than a 2 month old baby’s hand. Then you can just pull the spindle from the center as if you were ‘taking candy’ from the aforementioned babies hand.
^^^ The crankset is the SR Edge crankset you can see in the pictures above. AFAIK, it isn’t unique or cool. It’s just what came with the bike I’m rebuilding. However, I don’t have a spare crankset, I don’t want to destroy this crankset if I can avoid it, and its now become the principle of the thing, dammit!
Had a set of these on my wife’s bike. They aren’t worth the effort. If you’ve already stripped the extraction thread out and its seized onto the BB spindle I would suggest that you cut your losses and toss it. You’ll be able to pick up some 80/90s JIS ST cranks for next to nothing. Time to move on brother.