fixed cup removal - help please!?

[Dead Rats]

FIXED CUP REMOVAL

never been a problem before... until now. I have an old cup & cone BB and I want to get the fixed cup up out before powdercoating the frame.

My problem is that instead of the usual huge 36mm fixed cup (for which I have a trusty spanner), this BB uses a fixed cup which looks like an adjustable cup, with flats only 16mm apart... there's no real way I can see to get any leverage (tried and failed in the bench vice after a good few days of Plusgas to help).

Is this an LBS job? What would happen if I left it in and took it to be powdercoated - could I perhaps just fit an old discard-able adjustable cup in the LH side to protect the fixed cup's bearing surface? (no thought not!)

Your sage advice - and comments on my ignorance - are very much appreciated!

 

[chipper]

This type of fixed cup can be a real pig to remove,just about any tool that fits slip's off.Here's some tips;

jam the fixed cup in a strong vise,turn the frame clockwise .

Take to LBS

Final solution that always works, get someone to weld a long steel bar to the cup.
you will now have enough leverage to remove the most obstinate cup,it's called pragmatic engineering

Don't be temted to leave the old cup in,it will compromise your whole build.

 

[one-eyed_jim]

I've used Sheldon Brown's method with a big bolt and nut:

http://www.sheldonbrown.com/tooltips/bbcups.html

Scroll down to "Fixed-Cup Tools".

Worked like magic removing a Raleigh-pattern bottom bracket similar to yours from a Moulton Mk3.

 

[hubgearfreak]

it's 5/8" not 16mm.

what you need is a block of steel, perhaps 50x50x25mm, with a 5/8 slot milled out of it, and a 10mm hole through the middle. you can then bolt it to the cup with an M10 nut, bolt and washers and turn it with just about anything - big stilsons or a big adjustable.

a friendly engineers nearby should be able to make you this invaluable tool for a reasonable amount - mine was made by a friend in metalwork college

 

[pigman]

I probably dont understand sheldon's idea. The bolt/nut combo might just turn without moving the cup??

anyway, you need 2 x 16mm spanners to get an even turn on the cup, rather than turning just from one side. The vice method solves this problem. If the spanners slip, try a nut/bolt combo similar to sheldon's, but with a big washer to hold the spanners tight against the cup and avoid it slipping.

if youre really desperate, angle gring part of the cup to allow a better or wider grip

edit
I'll bow to hubbers knowledge at an imperial size, I was going on your description. 2 big pedal spanners??

 

[Dead Rats]

I probably dont understand sheldon's idea. The bolt/nut combo might just turn without moving the cup??

anyway, you need 2 x 16mm spanners to get an even turn on the cup, rather than turning just from one side. The vice method solves this problem. If the spanners slip, try a nut/bolt combo similar to sheldon's, but with a big washer to hold the spanners tight against the cup and avoid it slipping.

if youre really desperate, angle gring part of the cup to allow a better or wider grip

edit
I'll bow to hubbers knowledge at an imperial size, I was going on your description. 2 big pedal spanners??

thanks pigman... and everyone. I know what you mean by "probably don't understand Sheldon's idea" :?

 

[one-eyed_jim]

I know what you mean by "probably don't understand Sheldon's idea"

You may not, but it works.

The flats on these cups are very shallow. It's not easy to secure a cup of this kind in the flats of a vice, and harder still to manipulate two thin spanners effectively.

hubgearfreak's tool will work very well for this kind of cup, but Sheldon's method has the advantage of working with different designs of cup, and it's very cheap if you have the necessary tools to drive the big nut and bolt.

In a pinch I've used an old axle with a pair of track nuts, a socket on one end, and a good pedal spanner on the other.

 

[Dead Rats]

I know what you mean by "probably don't understand Sheldon's idea"

You may not, but it works.

The flats on these cups are very shallow. It's not easy to secure a cup of this kind in the flats of a vice, and harder still to manipulate two thin spanners effectively.

hubgearfreak's tool will work very well for this kind of cup, but Sheldon's method has the advantage of working with different designs of cup, and it's very cheap if you have the necessary tools to drive the big nut and bolt.

In a pinch I've used an old axle with a pair of track nuts, a socket on one end, and a good pedal spanner on the other.

yes the vice was no use!

just been to see 'bolt man' and got me an M16 bolt & nut (whopping 24mm spanner & socket @ the ready!) & lots of nice fat washers, wish me luck!

 

[monty dog]

Sheldon's big nut and bolt works because turning it clockwise increases the grip - getting a serrated washer underneath the head - or something to improve grip helps too.
Tack-welding a bar to the cup is easy too

 

[Dead Rats]

I know what you mean by "probably don't understand Sheldon's idea"

You may not, but it works.

The flats on these cups are very shallow. It's not easy to secure a cup of this kind in the flats of a vice, and harder still to manipulate two thin spanners effectively.

hubgearfreak's tool will work very well for this kind of cup, but Sheldon's method has the advantage of working with different designs of cup, and it's very cheap if you have the necessary tools to drive the big nut and bolt.

In a pinch I've used an old axle with a pair of track nuts, a socket on one end, and a good pedal spanner on the other.

hnnnggggggmmmmppphhhh!

following Sheldon's word to the letter, no joy as yet with a keen 13 stones of shove... just can't get the spanner to turn any more! :?

might try the serrated washer