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#51
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The one thing that couldn't go wrong, did go wrong.
In article , says...
I tried that. It won't go unless I get a narrower axle or make enough of a permanent bend in the stays that I can get this axle in. But I won't do the latter. I put about 10k miles on a Specialized Epic carbon fiber frame after I just jammed in the wider wheel. It was originally spaced for a 126mm wheel and I just spread the stays and put in a 130mm wheel. No problems at all. It just meant I had spread the stays every time I put the wheel back on. Not a big deal. I'm sure someone is still riding that frame. ------------- Alex |
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#52
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The one thing that couldn't go wrong, did go wrong.
Blair P. Houghton wrote: wrote: Blair P. Houghton wrote: I've got plenty of experience with mechanicals. Enough to know these two significant things: when you stress old metal, it doesn't behave the way new metal does; Sorry, I disagree, unless there's something special going on, like severe corrosion. 20 years of stress and release will change a crystalline matrix (and yes, all solids are crystals, just some aren't pure and regular). Welds and brazings weaken. Um... sorry, no. Not in any practical way, in this practical situation. You're worrying about things you don't have to worry about. I left the bike in the workstand, got two blocks of wood and one longer two-by-four, used the two-by-four to pry the dropouts further apart by putting pressure on the wood blocks. I used trial and error to get the exact 130mm spacing. The force was applied evenly and simultaneously to the inside of both dropouts. The frame passed a quick string alignment check, and the frame rode perfectly straight when it was all done. It all took 15 minutes or less. Nice job. Anecdotal, though. If you used the one side as the spring to deflect the other side then no actual attempt was made to ensure even deflection, so you got lucky. I was thinking about this a bit more, recalling exactly how I did it. It was actually two two-by-fours, and two other blocks of wood to fill up the space between the dropouts, arranged this way: Block, 2x4, 2x4, block. The 2x4s extended about 8" (as a guess) forward of the axle line, and perhaps 2.5 feet behind, and were parallel to each other. I spread the back end of the 2x4s, so they pivoted on their front ends, spreading the dropouts. They acted as second class levers. http://en.wikipedia.org/wiki/Lever The forces on each dropout were exactly the same. I figured the deflection would be the same. And it was. How far did you have to push the dropouts past 130mm to get them to spring back to 130mm? I didn't measure. It took about three or four tries to get it right. I've got a fair amount of experience bending metal. ;-) I just felt for the yielding. There's also the fact that we're talking about one kind of metal encased in another (the Campy lugs ... Was that supposed to be dropouts? I'm not confusing frame lugs with dropout lugs, if that's what you mean. The dropouts themselves are Campagnolo-made hardened lugs that Holdsworth welded to the Reynolds tubing. ?? That's not making sense to me. For one thing, isn't it brazed construction instead of welded? And regarding the lugs - do you have a picture? "It's easy in theory." :-) It's easy in practice, too. Some things are that way! But it's all up to you. - Frank Krygowski |
#53
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The one thing that couldn't go wrong, did go wrong.
Blair P. Houghton wrote:
If it was a beater or a new bike, I'd consider it good exercise. But this is my Holdsworth. One slip, and 22 years of history, maybe 40k miles, dumped on the junk-heap. I have a Holdsworth Super Mistral (Black/red panels), first "nice" frame I ever bought new, 1980. I toured on it, and then used it for a fixed gear bike and single-speed commuter. Probably not 40k miles, but at least a lot of the paint is missing... Yeah, "dogpiling". But maybe sharpening a point or two: My understanding is that "coldsetting" stays for alignment is routinely done after brazing, when new. I've been told and have read that some mass-produced (in bike terms) frames were commonly cold-set by greater amounts than what's being discussed here. Sheldon Brown on Holdsworth: Holdsworth The Holdsworthy company was a huge retail and mail order concern going back at least to the 30's. Eventually Holdsworthy bought out many other framebuilders such as Claud Butler and Freddie Grubb. Holdsworth frames until the 50's were really extraordinary, and from then until the mid 70's were simply quite nice. The orange and blue professionals were great riders, and their touring counterparts with the same interesting wrap-around seat cluster were very cool indeed. By the late 70's or early 80's, things started getting very mass produced. Holdsworth frames became the lowest priced frame going, rally just a step above many nice production bikes. Reality, though, is that even the later more mediocre examples really ride wonderfully. They are cheap thrills in the vintage lightweight world. For early 70's models in guideline condition (especially the orange ones) a price around $850 seems reasonable. Because Holdsworth frames were usually ridden hard, it may be very hard to find truly great examples. I know that I'm still looking! For later models with N.R. parts, a value around $550 seems reasonable. Open to correction: I understand the later Holdsworths were furnace brazed, which I guess would mean a minimum amount of constraint (no jigs) on the tubes as they were joined. Then, coldset to take a wheel. Making the point that "our" Holdsworths have probably already been coldset at least once. (Please see * below) There's lots of extra beef in there ("design" factor moot). Sheldon's caution is something anyone would have to include with this procedural. Sure, you could start out Force 10 and ruin a frame. Hence Sheldon's caution; but the somewhat dismissive tone of a few posters here, who have seen exactly this OLD adjustment done many times, speaks volumes. "NBD". Repeating, very common when OLD standards changed because, if for no other reason, flat repair, especially with packs and fenders on, is (maybe a whole lot) easier if the wheel slides in and out without having to spread the stays. In the rain, etc. Perhaps a direct question: Has anyone seen a frame being widened for 130 OLD ruined, in a "professional setting"? *Just to say: I also had a Roberts ("Club") touring frame, which was (allegedly, g) a low-volume, hand-brazed blah blah English 531 bike with Campy DO's; specs and measurements almost identical to the Holdsworth (I splurged on a fancy touring bike, back when I was touring, late 70's to mid-80's). I always thought the Holdsworth rode better, for half the price; this is partly why the Holdsworth hangs in my garage, while the Roberts lives with a Japanese rider/collector. --Tom Paterson |
#54
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The one thing that couldn't go wrong, did go wrong.
Just another data point - I guess now adding up to the "mountain" of data
points. I had a local shop here in Seattle "cold set" my mid 70s 530 tubing frame to 130 - no problems whatsoever. Slightly off topic - I had a Holdsworth "competition" model. I bought the frame in London around 1972. Took it home, built it up and rode it for years. Wish I still had it. Sloping fork crown, wrap around seat stays, kind of neat. Anyone in the group remember Harry Quinn frames? Anyway, unless it's a point of stubborn hubris, I just can't see why the OP would hesitate to get a quality shop to do a cold set. - Jon |
#55
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The one thing that couldn't go wrong, did go wrong.
[snip]
Dear Blair, I hope that you never have to decide whether to have a wart removed. True, warts are frequently removed by competent surgeons, but what if something went wrong? Carl Fogel |
#57
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The one thing that couldn't go wrong, did go wrong.
Blair P. Houghton wrote:
20 years of stress and release will change a crystalline matrix (and yes, all solids are crystals, just some aren't pure and regular). Welds and brazings weaken. I do a lot of frame repair and alignment to vintage frames and I've seen no evidence of that. I'm not confusing frame lugs with dropout lugs, if that's what you mean. The dropouts themselves are Campagnolo-made hardened lugs that Holdsworth welded to the Reynolds tubing. Your Campagnolo #1010 frame ends are mild steel. quite soft. It is not welded. It is brazed. I used to buy brazing flux from Holdsworthy ( really!) it was pink and 1600 degrees. You note that it is your prerogative to not change this frame. Absolutely right. Just don't invent reasons and try to pass them as truth. -- Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971 |
#58
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The one thing that couldn't go wrong, did go wrong.
Blair P. Houghton wrote:
If it was a beater or a new bike, I'd consider it good exercise. But this is my Holdsworth. One slip, and 22 years of history, maybe 40k miles, dumped on the junk-heap. wrote: I have a Holdsworth Super Mistral (Black/red panels), first "nice" frame I ever bought new, 1980. I toured on it, and then used it for a fixed gear bike and single-speed commuter. Probably not 40k miles, but at least a lot of the paint is missing... Yeah, "dogpiling". But maybe sharpening a point or two: My understanding is that "coldsetting" stays for alignment is routinely done after brazing, when new. I've been told and have read that some mass-produced (in bike terms) frames were commonly cold-set by greater amounts than what's being discussed here. -snip- Open to correction: I understand the later Holdsworths were furnace brazed, which I guess would mean a minimum amount of constraint (no jigs) on the tubes as they were joined. Then, coldset to take a wheel. -snip- Here's the later (final) Holdsworth facility on Oakfield road; no 'furnace brazing'. http://www.yellowjersey.org/hwfact.html I didn't see any 'hearth brazing'(as it was called then) when I was at the Putney facility in the early seventies either. My own '53 Raleigh _was_ built that way. It's been widened and even de-pretzeled after an horrific crash but rides straight to this day. Every day. -- Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971 |
#59
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The one thing that couldn't go wrong, did go wrong.
On Sun, 14 Aug 2005 22:14:27 GMT in rec.bicycles.tech, Blair P.
Houghton wrote: You say it's easy, why don't you pony up and indemnify the process against any sort of mechanical error for the $20k or so this frame is really worth to me. oh, bullpucky. no frame is worth that much, and you're just obsessive. PLONK. |
#60
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The one thing that couldn't go wrong, did go wrong.
A Muzi wrote: Here's the later (final) Holdsworth facility on Oakfield road; no 'furnace brazing'. http://www.yellowjersey.org/hwfact.html What is photo #7? It looks like the stress relief machine at Trek described by JB. Is it always women who build the wheels at large factories? |
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