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Old 03-28-24, 12:21 PM
  #44  
scarlson 
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Bikes: Ron Cooper touring, 1959 Jack Taylor 650b ladyback touring tandem, Vitus 979, Joe Bell painted Claud Butler Dalesman, Colin Laing curved tube tandem, heavily-Dilberted 1982 Trek 6xx, René Herse tandem

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Originally Posted by Pantah
Good news. As I suspected, the local frame builder can repair it no problem and can also convert it to threadless, which I've decided to do. No idea what the time frame will be like on getting it back or how much it will cost but neither is a particularly big deal. I'll get it when I get it and pay however much he wants. In the meantime, I can collect the last couple of parts I need to do the conversion, take the bar tape and shifters off and install the new headset races in the frame.
Just make sure the framebuilder knows not to heat up the rest of the fork very much. Those Klein forks that I have seen are Sakae Litage forks painted by Klein. They are bonded using epoxy, which may not respond well to heat. How much heat is difficult to say, without knowing the exact epoxy and whether or not it has been heat treated already at the factory, which some epoxys are to increase strength and resiliency. I have seen "do not exceed" numbers from 135F up to 300F in my reading of epoxy documentation. It is not the same as not burning the paint off a steel fork. It will require a good deal more care. Heat can and will conduct readily down the steerer and may soften the epoxy bonding the steerer to the crown if precautions aren't taken.

If I were doing the job, I would not take chances. I would submerge the forkblades and crown in a bucket of water, and I would prepare the internal sleeve and extension separately (braze together on the bench) and then silver braze the sleeve and extension to the fork in one quick operation.

That's just my opinion though. I've never had the chance to do it because the only bonded fork steerer failure I've ever had to fix was an early Vitus fork with an aluminum 1" threaded steerer (!!)
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Last edited by scarlson; 03-28-24 at 02:14 PM.
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