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Main
Date: 08 Sep 2007 07:08:51
From: Scott Gordo
Subject: Help! Cracked BB shell lug!
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I've discovered a massive crack in the bottom bracket lug of my
Reynolds 531 1975 Paramount track frame that runs along the entire
circumference at the base of the lug's seat tube opening.
To clarify, the crack is in the lug, not the seat tube, The lugs are
Nervex, but I think I remember reading that they used a different bb
lug, The crack runs along the bb shell, around the back, back across
the bb shell, and traces its way over the top of the down tube opening
to meet at the other side.
What a freakin' bummer!
Fixable? Recommendations? Welding in place would be cheap and I know a
guy but it sounds too hot, I don't know any brazers, maybe I need a
new lug installed? I'm not concerned about paint or anything, as this
isn't a show bike and it has already been crappily repainted. I just
don't want to *sniff* give her up.
Gah!
TIA.
Scott
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Date: 12 Sep 2007 03:19:14
From: datakoll
Subject: Re: Help! Cracked BB shell lug!
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the cracked lug raises an interesting question for all us low end
asian import lug frame owners who may have say cracked paint at a lug.
considering a TIG weld at the crack in discussion, how long a bead is
necessary at four bead points, given the load?
we all know how much bead the welder sez you need, 6-7 feet after an 2
hours adjusting equipment, making coffee and analyzing the problem, a
problem complicated by the obvious fact you are a moron who needs to
explain the crack 5 or 6 times.
but really would not 4 short beads do the job?
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Date: 11 Sep 2007 21:38:56
From: jim beam
Subject: Re: Help! Cracked BB shell lug!
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datakoll wrote:
> the cracked lug raises an interesting question for all us low end
> asian import lug frame owners who may have say cracked paint at a lug.
> considering a TIG weld at the crack in discussion, how long a bead is
> necessary at four bead points, given the load?
> we all know how much bead the welder sez you need, 6-7 feet after an 2
> hours adjusting equipment, making coffee and analyzing the problem, a
> problem complicated by the obvious fact you are a moron who needs to
> explain the crack 5 or 6 times.
> but really would not 4 short beads do the job?
you can cover the crack, but to remove the stress riser, you have to
fuse sufficient material to make the whole crack melt.
http://www.flickr.com/photos/38636024@N00/1363494401/
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Date: 11 Sep 2007 23:58:57
From: A Muzi
Subject: Re: Help! Cracked BB shell lug!
|
> datakoll wrote:
>> the cracked lug raises an interesting question for all us low end
>> asian import lug frame owners who may have say cracked paint at a lug.
>> considering a TIG weld at the crack in discussion, how long a bead is
>> necessary at four bead points, given the load?
>> we all know how much bead the welder sez you need, 6-7 feet after an 2
>> hours adjusting equipment, making coffee and analyzing the problem, a
>> problem complicated by the obvious fact you are a moron who needs to
>> explain the crack 5 or 6 times.
>> but really would not 4 short beads do the job?
jim beam wrote:
> you can cover the crack, but to remove the stress riser, you have to
> fuse sufficient material to make the whole crack melt.
> http://www.flickr.com/photos/38636024@N00/1363494401/
Yes, exactly right for an all-steel structure. Welding is a dismal
choice over a brazed steel joint. And some investigation about why it
cracked, possibly realignment to remove internal stresses, is time well
spent.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 11 Sep 2007 23:20:16
From: datakoll
Subject: Re: Help! Cracked BB shell lug!
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Andy deserves the '07 art trophy.
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Date: 11 Sep 2007 23:29:39
From: A Muzi
Subject: Re: Help! Cracked BB shell lug!
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datakoll wrote:
> Andy deserves the '07 art trophy.
Art is a Window Washer. Forever.
http://www.madison.com/wsj/home/local/index.php?ntid=134898
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 11 Sep 2007 23:18:55
From: datakoll
Subject: Re: Help! Cracked BB shell lug!
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FASTEST GUN IN THE WEST SYNDROME
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Date: 11 Sep 2007 23:15:17
From: datakoll
Subject: Re: Help! Cracked BB shell lug!
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On Sep 11, 2:54 am, sergio <serva...@df.unipi.it > wrote:
> On Sep 11, 6:27 am, A Muzi <a...@yellowjersey.org> wrote:
>
> > We fill in bronze for that. Here's an extreme case. The BB machine work
> > was yesterday afternoon:http://www.yellowjersey.org/mitch.html
>
> Amazing not just what you can do, but actually what people can afford
> to have you do for them
>
> Sergio
> Pisa
BULLDOZER!
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Date: 10 Sep 2007 23:54:33
From: sergio
Subject: Re: Help! Cracked BB shell lug!
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On Sep 11, 6:27 am, A Muzi <a...@yellowjersey.org > wrote:
> We fill in bronze for that. Here's an extreme case. The BB machine work
> was yesterday afternoon:http://www.yellowjersey.org/mitch.html
Amazing not just what you can do, but actually what people can afford
to have you do for them
Sergio
Pisa
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Date: 11 Sep 2007 14:51:54
From: A Muzi
Subject: Re: Help! Cracked BB shell lug!
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> A Muzi <a...@yellowjersey.org> wrote:
>> We fill in bronze for that. Here's an extreme case. The BB machine work
>> was yesterday afternoon:http://www.yellowjersey.org/mitch.html
sergio wrote:
> Amazing not just what you can do, but actually what people can afford
> to have you do for them
That page is a bit short of 'commerce'
And my employees learned basic techniques on projects like this where
the standard for 'victory' is low.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 11 Sep 2007 21:54:42
From:
Subject: Re: Help! Cracked BB shell lug!
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Andrew Muzi writes:
> We fill in bronze for that. Here's an extreme case. The BB machine
> work was yesterday afternoon:
http://www.yellowjersey.org/mitch.html
The Raliegh looks like it spent time on the SF waterfront with
exposure to ocean spray and fog.
Jobst Brandt
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Date: 11 Sep 2007 23:15:23
From: A Muzi
Subject: Re: Help! Cracked BB shell lug!
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> Andrew Muzi writes:
>> We fill in bronze for that. Here's an extreme case. The BB machine
>> work was yesterday afternoon:
> http://www.yellowjersey.org/mitch.html
jobst.brandt@stanfordalumni.org wrote:
> The Raliegh looks like it spent time on the SF waterfront with
> exposure to ocean spray and fog.
It's been ridden daily for work and errands over 30 years in humid
Madison WI through all seasons (one of our local seasons is 'road salt')
and lives out of doors.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 11 Sep 2007 03:44:42
From: Chalo
Subject: Re: Help! Cracked BB shell lug!
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jim beam wrote:
>
> Chalo wrote:
> >
> > jim beam wrote:
> >>
> >> er, the bb is cracked, not cracked apart. you cannot clean inside a
> >> crack unless you open it up. that means the stress riser remains.
> >
> > A fine bur on a Dremel tool makes quick work of prepping a crack for
> > repair by brazing.
>
> well, you can cut the crack out and refill the hole i suppose, but it
> wouldn't be as strong. and seriously, it would take extraordinary luck
> and inordinate messing about with a crack without opening or removing it
> to clean it sufficiently to guarantee a good properly wetted join down
> into the crack itself. without that, you're just lipsticking the pig
> and the stress riser remains.
I reckoned the thing to do would be open, clean, and flux the crack,
but not stop at filling it to the surface. I'd use a 45% fillet
forming silver wire and build up a decent 10mm or so fillet. That
should let the material in the surface of the fillet take a lot of
stress off the underlying steel. If brazed steel frames couldn't
tolerate flaws and irregularities on the insides of the joints, they'd
fail a lot more often. Most of them, lugged or filleted, are pretty
ugly in there.
Chalo
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Date: 11 Sep 2007 01:18:28
From: datakoll
Subject: Re: Help! Cracked BB shell lug!
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a farmer might find a suitable tube, cut in half, cut top in half, cut
snd file hole/slots for top half's tube bracing, file/grind/hammer
tube to fit BB, clamp, tig tube, tig tube end to BB ends.
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Date: 10 Sep 2007 21:46:12
From: vey
Subject: Re: Help! Cracked BB shell lug!
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datakoll wrote:
> a farmer might find a suitable tube, cut in half, cut top in half, cut
> snd file hole/slots for top half's tube bracing, file/grind/hammer
> tube to fit BB, clamp, tig tube, tig tube end to BB ends.
>
>
Yes, he might. Farmers are famous for making worn-out pieces of crap
last another year or two.
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Date: 11 Sep 2007 11:03:49
From: _
Subject: Re: Help! Cracked BB shell lug!
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On Mon, 10 Sep 2007 21:46:12 -0400, vey wrote:
> datakoll wrote:
>> a farmer might find a suitable tube, cut in half, cut top in half, cut
>> snd file hole/slots for top half's tube bracing, file/grind/hammer
>> tube to fit BB, clamp, tig tube, tig tube end to BB ends.
>>
>>
>
> Yes, he might. Farmers are famous for making worn-out pieces of crap
> last another year or two.
I think you misspelt decade.
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Date: 08 Sep 2007 16:12:26
From: John Thompson
Subject: Re: Help! Cracked BB shell lug!
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On 2007-09-08, Scott Gordo <blubberpuss@gmail.com > wrote:
> I've discovered a massive crack in the bottom bracket lug of my
> Reynolds 531 1975 Paramount track frame that runs along the entire
> circumference at the base of the lug's seat tube opening.
>
> To clarify, the crack is in the lug, not the seat tube, The lugs are
> Nervex, but I think I remember reading that they used a different bb
> lug, The crack runs along the bb shell, around the back, back across
> the bb shell, and traces its way over the top of the down tube opening
> to meet at the other side.
>
> What a freakin' bummer!
>
> Fixable? Recommendations? Welding in place would be cheap and I know a
> guy but it sounds too hot, I don't know any brazers, maybe I need a
> new lug installed? I'm not concerned about paint or anything, as this
> isn't a show bike and it has already been crappily repainted. I just
> don't want to *sniff* give her up.
Fixable, but not cheap. I fixed an old Atala "Record" frame that had
failed in this manner, and I'm still riding it more than 20 years later.
But you do need to know what you're doing WRT removing the old shell,
brazing in a new one, keeping it all properly aligned, and (unless
you're not too picky) a new paint job.
How much do you like this bike? I got the Atala for free -- the frame
was tossed by the previous owner -- and I was able to do all the labor
myself. When I needed a new commuter bike after some low-life stole
mine, I pulled the broken Atala out of storage and fixed it up. Been
riding it ever since.
--
John (john@os2.dhs.org)
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Date: 08 Sep 2007 18:55:39
From: Chalo
Subject: Re: Help! Cracked BB shell lug!
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jim beam wrote:
>
> er, the bb is cracked, not cracked apart. you cannot clean inside a
> crack unless you open it up. that means the stress riser remains.
A fine bur on a Dremel tool makes quick work of prepping a crack for
repair by brazing.
Chalo
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Date: 09 Sep 2007 06:44:31
From: jim beam
Subject: Re: Help! Cracked BB shell lug!
|
Chalo wrote:
> jim beam wrote:
>> er, the bb is cracked, not cracked apart. you cannot clean inside a
>> crack unless you open it up. that means the stress riser remains.
>
> A fine bur on a Dremel tool makes quick work of prepping a crack for
> repair by brazing.
>
well, you can cut the crack out and refill the hole i suppose, but it
wouldn't be as strong. and seriously, it would take extraordinary luck
and inordinate messing about with a crack without opening or removing it
to clean it sufficiently to guarantee a good properly wetted join down
into the crack itself. without that, you're just lipsticking the pig
and the stress riser remains.
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Date: 09 Sep 2007 12:12:54
From: Jambo
Subject: Re: Help! Cracked BB shell lug!
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"jim beam" <spamvortex@bad.example.net > wrote in message
news:zbGdnexys6kiZX7bnZ2dnUVZ_vfinZ2d@speakeasy.net...
> Chalo wrote:
>> jim beam wrote:
>>> er, the bb is cracked, not cracked apart. you cannot clean inside a
>>> crack unless you open it up. that means the stress riser remains.
>>
>> A fine bur on a Dremel tool makes quick work of prepping a crack for
>> repair by brazing.
>>
> well, you can cut the crack out and refill the hole i suppose, but it
> wouldn't be as strong. and seriously, it would take extraordinary luck
> and inordinate messing about with a crack without opening or removing it
> to clean it sufficiently to guarantee a good properly wetted join down
> into the crack itself. without that, you're just lipsticking the pig
> and the stress riser remains.
HAHAHAHA! Proven wrong again, lying fucktard! Now you spew more bullshit
like a wounded rat in a corner!
HAHAHAHAHA!
>
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Date: 10 Sep 2007 21:16:36
From: jim beam
Subject: Re: Help! Cracked BB shell lug!
|
Jambo wrote:
> "jim beam" <spamvortex@bad.example.net> wrote in message
> news:zbGdnexys6kiZX7bnZ2dnUVZ_vfinZ2d@speakeasy.net...
>> Chalo wrote:
>>> jim beam wrote:
>>>> er, the bb is cracked, not cracked apart. you cannot clean inside a
>>>> crack unless you open it up. that means the stress riser remains.
>>> A fine bur on a Dremel tool makes quick work of prepping a crack for
>>> repair by brazing.
>>>
>> well, you can cut the crack out and refill the hole i suppose, but it
>> wouldn't be as strong. and seriously, it would take extraordinary luck
>> and inordinate messing about with a crack without opening or removing it
>> to clean it sufficiently to guarantee a good properly wetted join down
>> into the crack itself. without that, you're just lipsticking the pig
>> and the stress riser remains.
>
> HAHAHAHA! Proven wrong again, lying fucktard! Now you spew more bullshit
> like a wounded rat in a corner!
fuck off moron. if you'd ever done metallography on attempted repairs
like this, you'll have seen little or no success at penetrating the
crack, only blobbing metal on top of it - and the stress riser
remaining. you shoot your mouth off all you want, but don't try to
obscure facts your i.q. can't comprehend.
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Date: 10 Sep 2007 11:14:44
From: vey
Subject: Re: Help! Cracked BB shell lug!
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Jambo wrote:
> HAHAHAHA! Proven wrong again, lying fucktard! Now you spew more bullshit
> like a wounded rat in a corner!
>
> HAHAHAHAHA!
So far, all I've been reading from you in this thread are insults. Not a
bit of practical suggestion in them.
Is this what you do?
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Date: 10 Sep 2007 20:19:44
From: _
Subject: Re: Help! Cracked BB shell lug!
|
On Mon, 10 Sep 2007 11:14:44 -0400, vey wrote:
> Jambo wrote:
>
>> HAHAHAHA! Proven wrong again, lying fucktard! Now you spew more bullshit
>> like a wounded rat in a corner!
>>
>> HAHAHAHAHA!
>
> So far, all I've been reading from you in this thread are insults. Not a
> bit of practical suggestion in them.
>
> Is this what you do?
Try pointing out one of "jim beam"'s errors.
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Date: 10 Sep 2007 21:07:58
From: vey
Subject: Re: Help! Cracked BB shell lug!
|
_ wrote:
> On Mon, 10 Sep 2007 11:14:44 -0400, vey wrote:
>
>> Jambo wrote:
>>
>>> HAHAHAHA! Proven wrong again, lying fucktard! Now you spew more bullshit
>>> like a wounded rat in a corner!
>>>
>>> HAHAHAHAHA!
>> So far, all I've been reading from you in this thread are insults. Not a
>> bit of practical suggestion in them.
>>
>> Is this what you do?
>
> Try pointing out one of "jim beam"'s errors.
So even when he says something right, it's wrong. O-k-a-y. People spend
(or waste) time "correcting" him because of what? They have nothing else
better to do?
Not trying to start anything, but want to get my -plonk- filters right.
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Date: 11 Sep 2007 15:04:23
From: Michael Press
Subject: Re: Help! Cracked BB shell lug!
|
In article <fc4pjo$rkd$1@news.datemas.de >,
vey <junker@ericvey.com > wrote:
> _ wrote:
> > On Mon, 10 Sep 2007 11:14:44 -0400, vey wrote:
> >
> >> Jambo wrote:
> >>
> >>> HAHAHAHA! Proven wrong again, lying fucktard! Now you spew more bullshit
> >>> like a wounded rat in a corner!
> >>>
> >>> HAHAHAHAHA!
> >> So far, all I've been reading from you in this thread are insults. Not a
> >> bit of practical suggestion in them.
> >>
> >> Is this what you do?
> >
> > Try pointing out one of "jim beam"'s errors.
>
> So even when he says something right, it's wrong. O-k-a-y. People spend
> (or waste) time "correcting" him because of what? They have nothing else
> better to do?
>
> Not trying to start anything, but want to get my -plonk- filters right.
There is always somebody new reading here. They must
not get the idea that jb's pronouncements can be taken
straight. Therefore his misleading statements must be
answered.
--
Michael Press
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Date: 08 Sep 2007 14:02:40
From: A Muzi
Subject: Re: Help! Cracked BB shell lug!
|
> jim beam wrote:
>> er, the bb is cracked, not cracked apart. you cannot clean inside a
>> crack unless you open it up. that means the stress riser remains.
Chalo wrote:
> A fine bur on a Dremel tool makes quick work of prepping a crack for
> repair by brazing.
Yes and an acid wash is helpful too
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 10 Sep 2007 11:18:37
From: vey
Subject: Re: Help! Cracked BB shell lug!
|
A Muzi wrote:
>> jim beam wrote:
>>> er, the bb is cracked, not cracked apart. you cannot clean inside a
>>> crack unless you open it up. that means the stress riser remains.
>
> Chalo wrote:
>> A fine bur on a Dremel tool makes quick work of prepping a crack for
>> repair by brazing.
>
> Yes and an acid wash is helpful too
I saw a bike on ebay a few weeks ago that had this exact problem. It had
been welded. The weld was very strong, but the bracket was not. It had
cracked again right next to the bead. I passed since I really didn't
need a new project, particularly one of dubious outcome.
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Date: 10 Sep 2007 21:25:32
From: A Muzi
Subject: Re: Help! Cracked BB shell lug!
|
>>> jim beam wrote:
>>>> er, the bb is cracked, not cracked apart. you cannot clean inside a
>>>> crack unless you open it up. that means the stress riser remains.
>> Chalo wrote:
>>> A fine bur on a Dremel tool makes quick work of prepping a crack for
>>> repair by brazing.
> A Muzi wrote:
>> Yes and an acid wash is helpful too
vey wrote:
> I saw a bike on ebay a few weeks ago that had this exact problem. It had
> been welded. The weld was very strong, but the bracket was not. It had
> cracked again right next to the bead. I passed since I really didn't
> need a new project, particularly one of dubious outcome.
Welding over a silver braze, or any braze for that matter, is a Welding
99 error - predictable failure.
To this specific bike: If it is cracked all around, he may be able to
get reasonable alignment which will eliminate the stress on the joint
which caused the crack. If so, as Chalo notes, a cleaned simple butt
joint silver brazed with full penetration should be adequate. Regarding
that type of crack see also:
http://www.yellowjersey.org/zito.html
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 10 Sep 2007 22:16:31
From: !Jones
Subject: Re: Help! Cracked BB shell lug!
|
On Mon, 10 Sep 2007 21:25:32 -0500, in rec.bicycles.tech A Muzi
<am@yellowjersey.org > wrote:
>Welding over a silver braze, or any braze for that matter, is a Welding
>99 error - predictable failure.
>To this specific bike: If it is cracked all around, he may be able to
>get reasonable alignment which will eliminate the stress on the joint
>which caused the crack. If so, as Chalo notes, a cleaned simple butt
>joint silver brazed with full penetration should be adequate. Regarding
>that type of crack see also:
>http://www.yellowjersey.org/zito.html
Yeah, I'd have to see it; however, I'd give odds that the frame is
dead. I once tried to repair a BB shell and it was an unmitigated
disaster. The guy had forced the cups into the wrong sides and musta
used a big cheater. I tried to build it up with a tig outfit and
rebore it... one of those ideas that should have worked, but didn't.
I was trying to do a favor for a friend and he ended up threatening to
sue me for a new frame.
Although, what that has to do with the current case, I haven't a clue.
Jones
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Date: 10 Sep 2007 23:27:40
From: A Muzi
Subject: Re: Help! Cracked BB shell lug!
|
> A Muzi <am@yellowjersey.org> wrote:
>> Welding over a silver braze, or any braze for that matter, is a Welding
>> 99 error - predictable failure.
>> To this specific bike: If it is cracked all around, he may be able to
>> get reasonable alignment which will eliminate the stress on the joint
>> which caused the crack. If so, as Chalo notes, a cleaned simple butt
>> joint silver brazed with full penetration should be adequate. Regarding
>> that type of crack see also:
>> http://www.yellowjersey.org/zito.html
!Jones wrote:
> Yeah, I'd have to see it; however, I'd give odds that the frame is
> dead. I once tried to repair a BB shell and it was an unmitigated
> disaster. The guy had forced the cups into the wrong sides and musta
> used a big cheater. I tried to build it up with a tig outfit and
> rebore it... one of those ideas that should have worked, but didn't.
> I was trying to do a favor for a friend and he ended up threatening to
> sue me for a new frame.
> Although, what that has to do with the current case, I haven't a clue.
TIG isn't the best choice as you'll need much effort cutting threads
across the various weld layers. I'd wonder about the brazed joints
nearby depending on total BTUs over time(?).
We fill in bronze for that. Here's an extreme case. The BB machine work
was yesterday afternoon:
http://www.yellowjersey.org/mitch.html
The classic Brit frame repair shops (Jackson, Hetchins, Holdsworthy) at
one time slit the BB shell, pressed the edges together, welded a seam
right across the shell then cut new threads in the smaller bore. Some
postwar bikes had steel threaded rings brazed into the shell on both
sides. A steel sleeve could be similarly brazed into a reamed shell then
properly cut with piloted taps I suppose.
Regarding your BB story, don't be discouraged. A few hundred 'charity'
jobs on BSOs will get you a better range of experience and you meet some
nice people that way.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 11 Sep 2007 17:25:02
From: Luke
Subject: Re: Help! Cracked BB shell lug!
|
In article <13ec68mqclljna6@corp.supernews.com >, A Muzi
<am@yellowjersey.org > wrote:
> TIG isn't the best choice as you'll need much effort cutting threads
> across the various weld layers. I'd wonder about the brazed joints
> nearby depending on total BTUs over time(?).
> We fill in bronze for that. Here's an extreme case. The BB machine work
> was yesterday afternoon:
> http://www.yellowjersey.org/mitch.html
"Today our customer said his headset felt funny.
He tried to adjust that bearing . . . to no avail "
LOL!
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Date: 10 Sep 2007 23:34:20
From: vey
Subject: Re: Help! Cracked BB shell lug!
|
!Jones wrote:
>
> Yeah, I'd have to see it
Wise move.
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Date: 08 Sep 2007 18:51:41
From: Chalo
Subject: Re: Help! Cracked BB shell lug!
|
Scott Gordo wrote:
>
> I've discovered a massive crack in the bottom bracket lug of my
> Reynolds 531 1975 Paramount track frame that runs along the entire
> circumference at the base of the lug's seat tube opening.
...
> Fixable? Recommendations? Welding in place would be cheap and I know a
> guy but it sounds too hot, I don't know any brazers, maybe I need a
> new lug installed? I'm not concerned about paint or anything, as this
> isn't a show bike and it has already been crappily repainted. I just
> don't want to *sniff* give her up.
If it were my bike, I'd try using 45% silver to add a fillet joint
over the cracked area. It would look funny on an otherwise lugged
bike, but that should fix it without running the lug filler everywhere
(if sensitively executed).
Chalo
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| |
Date: 08 Sep 2007 11:25:17
From:
Subject: Re: Help! Cracked BB shell lug!
|
On Sep 8, 12:45 pm, "Jambo" <-...@-.- > wrote:
> "jim beam" <spamvor...@bad.example.net> wrote in message
>
> news:WsGdnexSHoK_KX_bnZ2dnUVZ_hisnZ2d@speakeasy.net...
>
> > you must be mistaken - r.b.t "engineers" say steel never fatigues!
>
> Bullshit again.
>
>
>
> > seriously though, re-welding the crack is never more than a temporary
> > fix - you can never clean the metal interface sufficiently to get a bond
> > that removes the stress riser.
>
> Spoken like a true poseur - welders usually clean the parts before
> re-welding them. Ever been in a workshop? Thought not.
>
> > the only viable repair is shell replacement, and frankly, economics of
> > that are questionable if you take a decent repaint into account.
>
> Bullshit.
>
> > sentimental attachment aside, just look at a replacement frame. my
> > bianchi pista is dead straight, rides great, and it's dead cheap. you can
> > pick them up on craigslist even cheaper.
Great. Perfect and appropriate impression of jim - six spokes short -
beam.
--
Spike
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Date: 08 Sep 2007 11:15:34
From: A Muzi
Subject: Re: Help! Cracked BB shell lug!
|
Scott Gordo wrote:
> I've discovered a massive crack in the bottom bracket lug of my
> Reynolds 531 1975 Paramount track frame that runs along the entire
> circumference at the base of the lug's seat tube opening.
>
> To clarify, the crack is in the lug, not the seat tube, The lugs are
> Nervex, but I think I remember reading that they used a different bb
> lug, The crack runs along the bb shell, around the back, back across
> the bb shell, and traces its way over the top of the down tube opening
> to meet at the other side.
>
> What a freakin' bummer!
>
> Fixable? Recommendations? Welding in place would be cheap and I know a
> guy but it sounds too hot, I don't know any brazers, maybe I need a
> new lug installed? I'm not concerned about paint or anything, as this
> isn't a show bike and it has already been crappily repainted. I just
> don't want to *sniff* give her up.
Do not weld over a silver braze. Bad things will happen, really.
Contact a Waterford dealer (like us!) about a repair/respray, especially
if you are the original owner. Waterford has original decal sets for
Paramount owners.
Yes, IIRC most Kenosha Paramounts have a pressed (RFG?) shell with
Nervex 3-piece lug set.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 08 Sep 2007 11:14:13
From: richard
Subject: Re: Help! Cracked BB shell lug!
|
That being a classic frame, you ought to contact Waterford Cycles. The
folks that built the Paramounts in the 70s all went there.
It wouldn't be cheap, but they'd be more than happy to restore it.
Scott Gordo wrote:
> I've discovered a massive crack in the bottom bracket lug of my
> Reynolds 531 1975 Paramount track frame that runs along the entire
> circumference at the base of the lug's seat tube opening.
>
> To clarify, the crack is in the lug, not the seat tube, The lugs are
> Nervex, but I think I remember reading that they used a different bb
> lug, The crack runs along the bb shell, around the back, back across
> the bb shell, and traces its way over the top of the down tube opening
> to meet at the other side.
>
> What a freakin' bummer!
>
> Fixable? Recommendations? Welding in place would be cheap and I know a
> guy but it sounds too hot, I don't know any brazers, maybe I need a
> new lug installed? I'm not concerned about paint or anything, as this
> isn't a show bike and it has already been crappily repainted. I just
> don't want to *sniff* give her up.
>
> Gah!
>
> TIA.
>
> Scott
>
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Date: 08 Sep 2007 07:39:29
From: jim beam
Subject: Re: Help! Cracked BB shell lug!
|
Scott Gordo wrote:
> I've discovered a massive crack in the bottom bracket lug of my
> Reynolds 531 1975 Paramount track frame that runs along the entire
> circumference at the base of the lug's seat tube opening.
>
> To clarify, the crack is in the lug, not the seat tube, The lugs are
> Nervex, but I think I remember reading that they used a different bb
> lug, The crack runs along the bb shell, around the back, back across
> the bb shell, and traces its way over the top of the down tube opening
> to meet at the other side.
>
> What a freakin' bummer!
>
> Fixable? Recommendations? Welding in place would be cheap and I know a
> guy but it sounds too hot, I don't know any brazers, maybe I need a
> new lug installed? I'm not concerned about paint or anything, as this
> isn't a show bike and it has already been crappily repainted. I just
> don't want to *sniff* give her up.
>
> Gah!
>
> TIA.
>
> Scott
>
you must be mistaken - r.b.t "engineers" say steel never fatigues!
seriously though, re-welding the crack is never more than a temporary
fix - you can never clean the metal interface sufficiently to get a bond
that removes the stress riser. the only viable repair is shell
replacement, and frankly, economics of that are questionable if you take
a decent repaint into account.
sentimental attachment aside, just look at a replacement frame. my
bianchi pista is dead straight, rides great, and it's dead cheap. you
can pick them up on craigslist even cheaper.
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Date: 08 Sep 2007 13:45:31
From: Jambo
Subject: Re: Help! Cracked BB shell lug!
|
"jim beam" <spamvortex@bad.example.net > wrote in message
news:WsGdnexSHoK_KX_bnZ2dnUVZ_hisnZ2d@speakeasy.net...
> you must be mistaken - r.b.t "engineers" say steel never fatigues!
Bullshit again.
>
> seriously though, re-welding the crack is never more than a temporary
> fix - you can never clean the metal interface sufficiently to get a bond
> that removes the stress riser.
Spoken like a true poseur - welders usually clean the parts before
re-welding them. Ever been in a workshop? Thought not.
> the only viable repair is shell replacement, and frankly, economics of
> that are questionable if you take a decent repaint into account.
Bullshit.
> sentimental attachment aside, just look at a replacement frame. my
> bianchi pista is dead straight, rides great, and it's dead cheap. you can
> pick them up on craigslist even cheaper.
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Date: 08 Sep 2007 16:21:58
From: John Thompson
Subject: Re: Help! Cracked BB shell lug!
|
On 2007-09-08, Jambo <-@-.- > wrote:
> "jim beam" <spamvortex@bad.example.net> wrote in message
> news:WsGdnexSHoK_KX_bnZ2dnUVZ_hisnZ2d@speakeasy.net...
>>
>> seriously though, re-welding the crack is never more than a temporary
>> fix - you can never clean the metal interface sufficiently to get a bond
>> that removes the stress riser.
> Spoken like a true poseur - welders usually clean the parts before
> re-welding them. Ever been in a workshop? Thought not.
A 1975 Paramount would have been silver brazed, not welded. The shell
was probably a Nervex Pro stamped shell that failed at the base of the
tube socket. Welding a bead around the crack large enough to be
structurally sound would probably burn all the silver out of the
shell/tube joint, leaving you with a very weak joint (but a strong
shell, for what that's worth).
I fixed my brass brazed Atala which had failed in the same manner by
cutting the old shell into several pieces, carefully sweating the pieces
off the tubes (4 joints involved: ST/BB, DT/BB and 2 CS/BB joints),
fitting a new shell (investment cast, this time), which required
removing the chainstay bridge since the chainstay sockets were slightly
wider spaced than the original shell, getting it all aligned properly,
brazing it up, and repainting. Altogether a non-trivial task, but still
working fine after 20 years.
--
John (john@os2.dhs.org)
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Date: 08 Sep 2007 11:02:17
From: jim beam
Subject: Re: Help! Cracked BB shell lug!
|
Jambo wrote:
> "jim beam" <spamvortex@bad.example.net> wrote in message
> news:WsGdnexSHoK_KX_bnZ2dnUVZ_hisnZ2d@speakeasy.net...
>> you must be mistaken - r.b.t "engineers" say steel never fatigues!
>
> Bullshit again.
>> seriously though, re-welding the crack is never more than a temporary
>> fix - you can never clean the metal interface sufficiently to get a bond
>> that removes the stress riser.
>
> Spoken like a true poseur - welders usually clean the parts before
> re-welding them. Ever been in a workshop? Thought not.
er, the bb is cracked, not cracked apart. you cannot clean inside a
crack unless you open it up. that means the stress riser remains.
>
>> the only viable repair is shell replacement, and frankly, economics of
>> that are questionable if you take a decent repaint into account.
>
> Bullshit.
do some math mr. modulus. a good paint job will cost you $500 or more.
excluding the bb replacement. if you want to spend that much
repairing a $300 frame, that's your business but it makes no financial
sense.
>
>> sentimental attachment aside, just look at a replacement frame. my
>> bianchi pista is dead straight, rides great, and it's dead cheap. you can
>> pick them up on craigslist even cheaper.
>
>
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Date: 08 Sep 2007 15:04:39
From: Crescentius Vespasianus
Subject: Re: Help! Cracked BB shell lug!
|
j
>> Bullshit.
>
> do some math mr. modulus. a good paint job will cost you $500 or more.
> excluding the bb replacement. if you want to spend that much repairing
> a $300 frame, that's your business but it makes no financial sense.
--------------
When I use to take bikes like that to
the LBS, they would say that they could
put it in the dumpster for me. Now I
just put them in the dumpster myself.
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