Bottom bracket unscrew direction?

[Ming the Merciless]

Is it free yet?

 

[rogerzilla]

Is that an aluminium frame? They can get rather stuck. I had one stuck in a Cannondale and had to get the LBS to remove it in the end. I think the softer threads gall when overtightened, which is inevitable with a BB due to precession.

 

[andrew_s]

I think it's not so much precession, but salt-generated corrosion of the aluminium. The white powdery oxide is a fair bit bulkier than the original aluminium, so tight becomes impossible.

I had one (UN72) that needed me (90 kg) jumping up and down on the end of a 32 mm ring spanner to get out. In the end, the cartridge came out with the LH cup, the flanged bit having been pulled off the chainset end of the cartridge.
I'd put copper grease on the threads, but nothing on the inside of the cup.

 

[robgul]

When taking out a UN type BB cartridge it's usually easier to remove the non-drive side cup first - and when assembling put that cup back in first, just part way so it supports the cartridge coming in from the drive side - and yes, copper grease is your friend.

 

[simongt]

Apologies, I meant just for the threads, not the bearings - !

 

[T4tomo]

When taking out a UN type BB cartridge it's usually easier to remove the non-drive side cup first - and when assembling put that cup back in first, just part way so it supports the cartridge coming in from the drive side - and yes, copper grease is your friend.

This is a good tip, helps to prevent cross threading. bit washer a crank bolt also good tip to stop the tool slipping when undoing.