Bicycle Mechanics - Cracked Frame: Seat Stay - Seat Post Join. Can it be fixed?

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Hey, I was just riding my bicycle yesterday when it started 'squeaking' I didn't think much of it until the afternoon when I looked a bit closer and realised that the frame is cracked all the way through.
I"m not sure how/when this happened, but I'm not too keen on riding it now I know its there. 'catastrophic failure' comes to mind.
Here's a Photo:
http://lukecollison.com/bike/IMG_1021.JPG
So its an Old Raleigh 'Criterium 12 / Triathlon frame I got second hand about a year ago. Can this be fixed? Welded back together or something? Its Reynolds 501 Tubing (or at least some of it is).
I"m located in London, UK so any advice on where I can get it fixed would also be appreciated.
The Bike:
http://lukecollison.com/bike/IMG_1012.JPG
The Crack:
http://lukecollison.com/bike/IMG_1029.JPG
A couple more photos here:
http://lukecollison.com/bike/
-
I"d prefer to just fix the frame cheaply as I just had another bicycle stolen in London (TRek 5.3 FX) and It seems inevitable here that it will happen again. Hence I"d like to fix this up, to ride for 6 months before its stolen as well.
Or I guess replace the frame. but that involves more work, moving all the bits and bobs over to a new frame. And I"m lazy, and need something to ride to work each day.
BCRider
08-20-08, 01:33 AM
It'll require some damage to the paint but you can get that brazed back together and it'll be fine. But the paint for about 3 inches away all around the crack will need to be removed prior to the brazing work
Where would I do that? get it brazed back together? And do I need to strip the bike to do that?
I"m not fussed about the paint. Its an old knocked up bike anyway. What are the approximate costs of fixing it?
kellyjdrummer
08-20-08, 05:55 AM
You don't braze (brass welding) aluminum'to start with. You would have to "electro weld" it. TIG or MIG would be one solution.
You don't think you could migrate all those parts in a day?
familyguy
08-20-08, 06:20 AM
OP bike is not aluminium, its steel, right?? Braze it.
A fix might depend on how severely it is cracked. A good repairer can tell you pretty quickly.
Jim
nitropowered
08-20-08, 06:42 AM
That thing is steel. It can be easily brazed back and then you will probably have to ream out the seattube so the post will fit back in
ochizon
08-20-08, 06:51 AM
I would tig it anyway, but brazing should hold.
kellyjdrummer
08-20-08, 06:53 AM
I read "Reynolds 501 Tubing" and assumed it was Al.
Its a Reynold 501 Cromoly steel frame - not an Aluminium frame.
What is the cost for the brazings etc? - is it going to be cost efficient to have it fixed up?
its not a particularly classy frame. It only cost me £50.00 so i don't want to spend more than that on repairing the frame.
HillRider
08-20-08, 08:04 AM
Check with an LBS in your area for a recommend local frame builder to do the repair.
There is no way we can estimate the cost from here but if you describe the problem the builder can give you a good estimate. Do you have a "Yellow Pages" phone book? There should be listings for "Bicycle Repair" and perhaps a frame builder is included.
spider-man
08-20-08, 08:18 AM
Definitely is steel, definitely is repairable, definitely should be rebrazed. I would take it into the LBS, and if they can't fix it, they should be able to direct you to someone who can.
MichaelW
08-20-08, 11:33 AM
Its whether the repair is cost effective; certainly not if you go with a premium framebuilder.
Try Bicycle Workshop in Notting Hill or Kiwi Bikes.
London Cycling Campaign may know.
501 is pretty thick and unbutted so it may be worth learning to wield a brazing torch tourself.
G piny parnas
08-20-08, 11:58 AM
ya -- braze it--- but weld a stress rod too---- are you, well, kinda heavy--- looks like a single speed--- are you a messenger--- get a Ti frame!
I have emailed kiwicycles and will try this Bicycle workshop lot.
I'm about 80-85kg, 182cm tall. so not particularly heavy.
I bought it on gumtree about 8 months ago. I think the fault may have been there for a while and i'd not noticed it. I rode it for a few months and then was riding another bike lately, until it was stolen.
And yeah its set up as a single speed - gears are over-rated in London. (its so flat here + all the traffic lights its not necessary).
I just had a different and more expensive bike stolen a few weeks ago, so I"m in a bit of a "dont' spend money on bikes they just get stolen" frame of mind. Hence i'm looking for a cheap fix.
oh and I"m not a messenger but I do work in The City
I was told today by someone in E1 Cycles down near Aldgate that it can't be fixed - but I don't think he knows much about bicycles.
chris101
08-20-08, 02:51 PM
If you do the prep work yourself I'm sure you'll be able to find a metal workshop somewhere that'll braze it together for the cost of a few pints of ale, if you were 150 miles north of London I could point you in the direction of one such specialist who'd do it for next to nothing. No need to Tig weld it, brazing can be incredibly strong if done properly.
I don't think you can weld 501, just braze it.
Mercian in Derby will fit a whole new seat stay for £55.00 but I would guess they could do it simpler and cheaper than that, however. Talk to them. If they put a new seat stay on it it'll be better than new.
Of course they're a LONG way from you and I don't know how much shipping would be but I bet they could recommend someone in London.
http://www.merciancycles.com/renovation.asp
BCRider
08-20-08, 08:39 PM
Luke, search your area for a general welding shop. Call them and ask if they do silver soldering and brazing or only welding.
MOST brazed frames were done using a lower temperature alloy or a higher temperature silver braze. Either way be sure to advise the guy running the torch that the joint holding the end tab is likely brazed on with a lower temperature type of brazing or silver brazing so he can alter what he uses accordingly.
And if you can do your own cleanup by removing the paint for about 3 to 4 inches all around where the joint will need to be brazed you'll save some money since the guy doing the job won't need to do it for you. Especially wire brush away any signs of rust at the crack. But don't use abrasives that will alter the joint itself.
A quick job like this shouldn't cost much at all. In fact if you show up right near quiting time on a Friday with a 6 pack under your left arm you may not need to spend anything else.
As for strippign the bike as long as you can remove the seat post and unmount the brake cable to move the burnable stuff well away from the worksite you'll be fine. In fact clean out the seat tube and post so they are not greasy and take it to the shop "dry" with the metal cleaned. Once brazed you can re-insert the post and re-mount the cable and ride home. Some badly matching paint to protect the metal from rust and you'll have a nice cobbly looking frame that no self respecting bike thief would be seen dead on..... Mind you I can't help you with the non self respecting thieves that just want to ride your bike to the other side of town and then dump it....
I would tig it anyway, but brazing should hold.
Agree, it would probably be faster and hold well. The break being through tip of the seatstay, not at the brazed joint but at what appears to be a break in the steel through a previously corroded area, maybe a crack. I am sure a bronze mass around the cleaned up edges would work too, but might require more filing.
If you tig weld it, aren't you going to have a cascade effect where welding the stay back together will melt the brazing where it's brazed to the lug? Then if you tig it there you'll melt the brazing for the whole lug and have to weld that, then the stay on the other side for the same reason?
mhuntwork
08-21-08, 08:17 AM
I don't think you can weld 501, just braze it.
Mercian in Derby will fit a whole new seat stay for £55.00 but I would guess they could do it simpler and cheaper than that, however. Talk to them. If they put a new seat stay on it it'll be better than new.
Of course they're a LONG way from you and I don't know how much shipping would be but I bet they could recommend someone in London.
http://www.merciancycles.com/renovation.asp
You can weld Chromoly. TIG weld with chromoly filler rod like stated below. You can't MIG or stick with CS is all.
If you tig weld it, aren't you going to have a cascade effect where welding the stay back together will melt the brazing where it's brazed to the lug? Then if you tig it there you'll melt the brazing for the whole lug and have to weld that, then the stay on the other side for the same reason?
Maybe with the brass at the broken tip of the seat stay, there isn't that much steel on that small broken bit. You will definitely have to be careful and use a heat sink. I don't know about melting all the old brass in the entire seat lug. Even with a TIG arc, that might take a bit of time. The whole idea of TIG is taking very little time and limiting the work to the break.
Thanks for all the tips and recommendations.
Mercian are a bit far away i think. - I also found somewhere in Lincolnshire who would do it for £40. btu again they are hours away. (and I don't own a car).
So if I clean it up myself: remove the paint from the area - using metal brush did you say?
And find a local welding place that can do silver soldering and brazing - perhaps they can fix it up for me quick smart?
how is that bit all held together anyway? The crack is a bit odd looking - ie is it the steel tubing that has broken?
San Rensho
08-21-08, 09:36 AM
I wouldn't try brazing that. If the crack is in solid metal, have someone try arc welding it. Torch welding will only melt the solder in the whole seat tube cluster and everything will fall apart.
Arc welding may well heat it up too much also, but a welder that is quick with a small amount of weld material should be able to do it.
BikingGrad80
08-21-08, 09:46 AM
I'd say that frame's day is over and it isn't worth the trouble. It looks very rusty on the inside. You could spend $100 fixing it only to have it fail somewhere else a week later. I'd say buy a new frame or get a cheap used one off ebay.
Crank57
08-21-08, 10:20 AM
Most of those 501 Cro Mo steel tube frames were only Cro Mo in the main triangle. The seat stays were usually regular carbon steel, or a little better, Hi Tensile steel. The material they put this together with was silver solder, sil-phos, or bronze brazing alloy. It would be very difficult to weld this together due to contamination of all the steel with the brazing alloy in the area. Also, most welding shops will not be skilled at welding such thin tubing, even if it were not contaminated. On the other hand, any trade shop that works with thin sheet material should have the skills needed. These would include auto body shops, radiator/muffler shops and some plumbers who work with silver soldered copper and of course bike shops.
I don't know what type stores you have over there, but here in the states I could purchase a MAPP gas torch and flux and Sil-Phos brazing rods for about $35 to $50 in a building supply store or an auto parts store and do it myself. Of course, I'm a tool junkie so I always look at doing things myself if it's an opportunity to buy some tools involved.
If I got this done at a body shop or bikeshop or similar it would cost about the same.
Most important thing about brazing this together is clean out the joint with a good stiff steel wire brush.
G piny parnas
08-21-08, 10:41 AM
nice
DannoXYZ
08-21-08, 01:51 PM
Don't forget plumbers can probably do this repair as well. Heck, if you were here, I'd invite you over and fix that right up for you. Won't take more than 5-minutes. You'll want to braze that to repair. That's the way the bike was originally built and you don't want to introduce too many dissimilar metals into that joint.
I've got an offer to repair it from someone in Lodon - who hopefully knows what he's doing.
also someone else sent me a link to this - http://www.ceeway.com/Top%20Eyes.htm
It does seem like the probelm is the Top Eye has rusted or cracked or something. so its not the actual tubing.
turns out though that he is just goign to TIG weld it - which seems perhaps not the best approach? based on the responses here
I don't really know. I
DannoXYZ
08-22-08, 12:20 PM
Get these two numbers:
1. temperature of HAZ in TIG-welding
2. melting temperature of brass used in assembling original joint.
These numbers will tell you something.
BCRider
08-22-08, 06:45 PM
I would make an excuse to not show up and go look elsewhere. Low temp brazing similar to what was originaly used is the best solution here. And if the stay end was rusted a bit from the back then it's easier and less damaging to fill it with some extra filler.
With the brazing option you won't need to worry about damage to the inside sizing of the seat tube. But if you have it welded then it WILL shrink appreciably and you'll need to deal with getting it reamed or ground out so the seat post will fit in again. So avoid welding and stick with brazing for this repair.
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