Any obscure BB removal suggestions before I go the sledge hammer route??

[Uncle Grumpy]

You could try acetone/atf mixture.

Beat me to it!

My father restores vintage farm equipment which are the pin-up girls of Rusted Crap Quarterly and he swears by the ATF/acetone mix. I've used it to soak seized suspension bolts on car restos with success too.

I have welded a piece of steel bar across a steel BB cup - that worked but in fairness the heat from the MIG welder probably helped crack the seal and contributed to the BB cups freedom.

Grumps

 

[mdvineng]

Atf and iso p2 when you have plastics or paint that you want to preserve.

Iso p2 = isopropanol 2

 

[novocaine]

if it's turn a thread then stopped it's possible it's not seized and instead it's skipped a thread.
no way to remove it but to cut it out at that point.

remove the non drive side first, then try to turn out the drive side, but if that doesn't work it's time to break out the sharp tools.

 

[Twozaskars]

Similar to the welding idea, I once just stuck the mig in and welded the bb shaft to the housing, and turned it out with a crank arm bolted on. Like the atf idea though.

 

[awac]

Beat me to it!

My father restores vintage farm equipment which are the pin-up girls of Rusted Crap Quarterly
Grumps

If I now win the lottery I will start a magazine called Rusted Crap Quarterly, (that gave me my morning chuckle)….It would work, I can not resist rusted cheap crap, and I am not alone.