Bicycle Mechanics - Seized bottom bracket

i have an 80's Atala bike. i replaced many parts and got to the bottom bracket last (did things out of order). It used to have a cotter pin system and it was worn out. I removed the cranks and the non-drive side lockring and even the spindle, bearings, etc. The only part left to remove is the drive-side locking cup. I know that it's an Italian style threading (right handed) on both sides. I've tried almost everything to remove that cup. After being unsuccessful trying to remove it, I soaked it in liquid wrench for two days and tried again... Nothing. I drilled slots into the cup to created a way to put a flat headed tool in and improvised a large torque wrench. Again nothing. I am out of ideas. What else can i do?

Put the bike cup in a vice and use the frame it self to crank that thing out. Since the frame will be in a flat position will be easier to apply torque in my opinion (have done this twice all my life). And the frame won't be in risk of a scratch or a dent if the tools slip. I'm assuming you don't have the shop tools and a good grip to hang the bike firmly.

Good luck :)

If you don't care about the paint. Hit it with a torch and then attempt removal.

For some of the tougher BB's I stick a long piece of gas-line pipe over the end of the wrench to give me a big ol' lever. That usually gives me enough leverage to bust it loose. It's sort of the same concept as putting the BB in the vise and using the frame as leverage- just backwards.

Try the Sheldon Tool.

A cottered crank suggests the bike may be older than 1980s. What does the fixed cup look like? Does it have flats for a standard fixed cup wrench to grab, or perhaps notches like this (found on my 1974 Atala):
http://www.os2.dhs.org/~john/atala-fixed-cup.jpg

I had a devil of a time getting that cup out. Sheldon's tool failed for me, but the professional version eventually managed to get it out:
http://www.os2.dhs.org/~john/enox-tool.jpg

A cottered crank suggests the bike may be older than 1980s. What does the fixed cup look like? Does it have flats for a standard fixed cup wrench to grab, or perhaps notches like this (found on my 1974 Atala):
http://www.os2.dhs.org/~john/atala-fixed-cup.jpg

I had a devil of a time getting that cup out. Sheldon's tool failed for me, but the professional version eventually managed to get it out:
http://www.os2.dhs.org/~john/enox-tool.jpg

That's the exact cup taht I have. I don't have the specs on the bike, I just guessed 80's. But yeah, that's the sob that won't budge... haha

Punch and hammer. Better, punch mounted in an air hammer. put the punch in one of the notches, pointed in the direction you want to turn, tangent to the shell, and hammer. Heat would help too, but if you care about the paint, is probably out.

hit the face of the cup a few times with a hammer, to loosen the corrosion. works for me.
then use the punch and hammer to turn it.

So i bought a propane torch, shot it onto the cup and housing for a good 5 minutes, took a hammer to it to break whatever bonds were there, then twisted it right off. Thanks for the help!!