Help! Cracked BB shell lug!

[Scott Gordo]

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

 

[jim beam]

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.

 

[richard]

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
>

 

[A Muzi]

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

 

[Jambo]

"jim beam" <[email protected]> wrote in message
news:[email protected]...
> you must be mistaken - r.b.t "engineers" say steel never fatigues!

******** 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.

********.

> 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.

 

[jim beam]

Jambo wrote:
> "jim beam" <[email protected]> wrote in message
> news:[email protected]...
>> you must be mistaken - r.b.t "engineers" say steel never fatigues!
>
> ******** 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.
>
> ********.

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.
>
>

 

[[email protected]]

On Sep 8, 12:45 pm, "Jambo" <[email protected]> wrote:
> "jim beam" <[email protected]> wrote in message
>
> news:[email protected]...
>
> > you must be mistaken - r.b.t "engineers" say steel never fatigues!
>
> ******** 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.
>
> ********.
>
> > 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

 

[Chalo]

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

 

[Chalo]

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

 

[A Muzi]

> 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

 

[John Thompson]

On 2007-09-08, Scott Gordo <[email protected]> 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 ([email protected])

 

[John Thompson]

On 2007-09-08, Jambo <[email protected]> wrote:

> "jim beam" <[email protected]> wrote in message
> news:[email protected]...
>>
>> 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 ([email protected])

 

[Crescentius Vespasianus]

j
>> ********.
>
> 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.

 

[jim beam]

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.

 

[vey]

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.

 

[datakoll]

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.

 

[vey]

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 ****
last another year or two.

 

[A Muzi]

>>> 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

 

[!Jones]

On Mon, 10 Sep 2007 21:25:32 -0500, in rec.bicycles.tech A Muzi
<[email protected]> 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

 

[vey]

!Jones wrote:

>
> Yeah, I'd have to see it

Wise move.