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 Post subject: b/b cup
PostPosted: Fri Jul 16, 2010 9:25 pm 
Retro Guru

Joined: Wed Nov 04, 2009 9:57 pm
Posts: 641
before trying all the differant methods, , have you tried warming up bottom bracket shell first, using either a hot air gun or a gas burner, this will have the effect of breaking the seal between casing and the cup, also a few squirts of WD40 help.

you may have to do it a few times

the ultimate tool to make, is a length of screwed rod that fits inside the hole in the cup, and is approx 4 inches longer then the width of the bottom bracket. you need 4 nuts to fit the screwed rod.
fit 2 nuts to one end of the screwed rod and weld both nuts to the screwed rod.
fit the third nut and screw down approx 2 inches onto the screwed rod and weld onto the rod.
to remove a tight cup form either side of the bottom bracket, fit the screwed rod from the inside of the cup fit the 4th nut with a washer and tighten,
on the fixed cup, which is left hand thread, this will undo the cup.
to remove the adjustable cup, tighten the nut against the cup and use the 2 welded nut to undo it.

have had my tool for over 30 years and its still as good as the day it was made and has removed tens of b/bracket cups.


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 Post subject: Re: b/b cup
PostPosted: Sat Jul 17, 2010 9:32 am 
Gold Trader
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Joined: Wed May 20, 2009 1:29 pm
Posts: 10798
Location: Manchester, UK
orbeas wrote:
before trying all the differant methods, , have you tried warming up bottom bracket shell first, using either a hot air gun or a gas burner, this will have the effect of breaking the seal between casing and the cup, also a few squirts of WD40 help.

you may have to do it a few times

the ultimate tool to make, is a length of screwed rod that fits inside the hole in the cup, and is approx 4 inches longer then the width of the bottom bracket. you need 4 nuts to fit the screwed rod.
fit 2 nuts to one end of the screwed rod and weld both nuts to the screwed rod.
fit the third nut and screw down approx 2 inches onto the screwed rod and weld onto the rod.
to remove a tight cup form either side of the bottom bracket, fit the screwed rod from the inside of the cup fit the 4th nut with a washer and tighten,
on the fixed cup, which is left hand thread, this will undo the cup.
to remove the adjustable cup, tighten the nut against the cup and use the 2 welded nut to undo it.

have had my tool for over 30 years and its still as good as the day it was made and has removed tens of b/bracket cups.


Hi and thanks for the advice! Do you have a photo you could post of this tool?


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 Post subject:
PostPosted: Sat Jul 17, 2010 10:06 am 
Retro Guru

Joined: Sun Dec 14, 2008 2:11 pm
Posts: 303
I independently arrived at the same method as the late great Mr Brown, with a slight variation. I didn't have a socket that would fit. So the solution I came up with was a nice long bolt with a tube as a sleeve on the bolt so I could get a spanner on both bolt ad nut to tighten it fully.

Once completely tightened it didn't take too much force to move the cup. Having said that I did use a five foot steel tube over the handle of my adjustable as a breaker bar! Since then I've always used this on fixed cups.

One important thing though, tighten the nut and bolt as hard as you can before attempting to remove the cup. If it's not tight enough it might slip suddenly and you don't want that to happen when you're leaning 13 stone on the spanner!

As for the heat method it's not particularly reliable. Better to apply a few well judged taps with special workshop tool #1 to the cup first. If there's something like rust "gluing" the components together this will break it. The heat method will work nicely on things like old grease, but it is unlikely to work well on rust. If you could heat the shell without heating the cup it might work, but that is very difficult without specialist equipment. I've worked in engineering shops where they have the kit to freeze one component while heating the other, but it would be fairly difficult to improvise at home.

Cheers,

Gareth


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 Post subject:
PostPosted: Sat Jul 17, 2010 10:11 am 
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Joined: Wed May 20, 2009 1:29 pm
Posts: 10798
Location: Manchester, UK
GarethPJ wrote:
I independently arrived at the same method as the late great Mr Brown, with a slight variation. I didn't have a socket that would fit. So the solution I came up with was a nice long bolt with a tube as a sleeve on the bolt so I could get a spanner on both bolt ad nut to tighten it fully.

Once completely tightened it didn't take too much force to move the cup. Having said that I did use a five foot steel tube over the handle of my adjustable as a breaker bar! Since then I've always used this on fixed cups.

One important thing though, tighten the nut and bolt as hard as you can before attempting to remove the cup. If it's not tight enough it might slip suddenly and you don't want that to happen when you're leaning 13 stone on the spanner!

As for the heat method it's not particularly reliable. Better to apply a few well judged taps with special workshop tool #1 to the cup first. If there's something like rust "gluing" the components together this will break it. The heat method will work nicely on things like old grease, but it is unlikely to work well on rust. If you could heat the shell without heating the cup it might work, but that is very difficult without specialist equipment. I've worked in engineering shops where they have the kit to freeze one component while heating the other, but it would be fairly difficult to improvise at home.

Cheers,

Gareth


Using your variation on the Sheldon Brown method, did you use something (or someone :shock: ) to secure / steady the frame? Good tip with the steel bar extension, I definitely couldn't get enough leverage with my measly 12" spanner to see any fixed cup movement, and by God I tried! :lol:


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 Post subject:
PostPosted: Sat Jul 17, 2010 11:52 am 
Dirt Disciple

Joined: Mon Dec 28, 2009 7:06 pm
Posts: 51
GarethPJ wrote:
The heat method will work nicely on things like old grease, but it is unlikely to work well on rust.


however unlikely it may be, it does work on rust. 8)


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 Post subject:
PostPosted: Sat Jul 17, 2010 9:53 pm 
Retro Guru

Joined: Wed Dec 10, 2008 9:19 am
Posts: 2095
Location: Sheffield, top city
one other thing to add, you probably know this but just in case.
english is a left hand thread, so undo clockwise. Italian is the opposite, french I dont know?


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 Post subject:
PostPosted: Sun Jul 18, 2010 2:24 am 
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Joined: Wed May 20, 2009 1:29 pm
Posts: 10798
Location: Manchester, UK
pigman wrote:
one other thing to add, you probably know this but just in case.
english is a left hand thread, so undo clockwise. Italian is the opposite, french I dont know?


to quote Sheldon Brown:

To remove a right-threaded fixed cup (French or Italian), tighten the bolt with the socket wrench from the inside of the bottom bracket, holding the nut with the box wrench. Once the bolt is as tight as can be, keep on tightening it, until the cup screws itself out. Once the cup starts to move, turn both wrenches together.

To remove a left=threaded (British, Swiss or Raleigh) fixed cup, hold the bolt with the socket wrench and turn the nut with the box wrench.


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 Post subject:
PostPosted: Sun Jul 18, 2010 9:36 am 
Retro Guru

Joined: Sun Dec 14, 2008 2:11 pm
Posts: 303
pigman wrote:
one other thing to add, you probably know this but just in case.
english is a left hand thread, so undo clockwise. Italian is the opposite, french I dont know?


Good point. It's amazing how many people who should know better try to unscrew an english fixed cup anti-clockwise.


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 Post subject: bottom bracket
PostPosted: Sun Jul 18, 2010 5:45 pm 
Retro Guru

Joined: Wed Nov 04, 2009 9:57 pm
Posts: 641
Heat is the only way with some bottom brackets.

just had to remove 2 bottom brackets from a Rossin and a Guerchotti

and they would not have come out without the oxy/act torch.

especially with alloy bottom brackets as the alloy reacts with the steel and they weld themselves together.

also without heat to expand the threads outwards there is a chance that the alloy cup will rip the threads off the bottom bracket.


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 Post subject: Re: b/b cup
PostPosted: Sun Jul 18, 2010 5:46 pm 
Retro Guru

Joined: Wed Nov 04, 2009 9:57 pm
Posts: 641
Dead Rats wrote:
orbeas wrote:
before trying all the differant methods, , have you tried warming up bottom bracket shell first, using either a hot air gun or a gas burner, this will have the effect of breaking the seal between casing and the cup, also a few squirts of WD40 help.

you may have to do it a few times

the ultimate tool to make, is a length of screwed rod that fits inside the hole in the cup, and is approx 4 inches longer then the width of the bottom bracket. you need 4 nuts to fit the screwed rod.
fit 2 nuts to one end of the screwed rod and weld both nuts to the screwed rod.
fit the third nut and screw down approx 2 inches onto the screwed rod and weld onto the rod.
to remove a tight cup form either side of the bottom bracket, fit the screwed rod from the inside of the cup fit the 4th nut with a washer and tighten,
on the fixed cup, which is left hand thread, this will undo the cup.
to remove the adjustable cup, tighten the nut against the cup and use the 2 welded nut to undo it.

have had my tool for over 30 years and its still as good as the day it was made and has removed tens of b/bracket cups.


Hi and thanks for the advice! Do you have a photo you could post of this tool?


ok will do, will make one if you want ???


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