Classic & Vintage - Clamp-on FD question
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Will a 31.8 clamp-on FD fit onto my 30mm o.d. seat tube?
If not, does anyone sell a shim...or do I fashion my own?
(These early 70's Schwinn Super Sport rebuilds are causing me more than a few sizing headaches!)
01-03-13, 05:03 PM
I bought a huge roll of shim stock from mcmaster.com. I'll be happy to cut you a piece if you like. This should last me a lifetime. You might be able to make a shim with a beer can. The material is very thin, and you can cut it with scissors.
The shim stock I bought is .02" thick, 6 inches wide, and 100" long. It cost me $12.17.
01-03-13, 07:18 PM
The nominal shim thickness needed by the OP is 0.9mm or approximately 1/32". Hardware stores probably have sheet aluminum around this thickness, might charge several dollars for it though.
1-1/2 wraps of 0.020" shim should work also. Lots of options.
Thanks for the kind offer, Tom, e-mail has been sent.
I guess I shouldn't be turned off by the beer can method. Although rudimentary' it is probably effective. I'm growing weary of hunting for 21.1 long-throw quill riser stems and 30mm seat post clamps!
I've read about using scotch tape...is that valid for some applications, or total hokey?
01-03-13, 11:52 PM
I wouldn't use anything that soft (except as a temporary stopgap). It will tend to compress over time and lose preload.
01-04-13, 06:43 AM
In my experience with the Schwinn fillet brazed seat tubes, I just went smaller, forced the band wider, and added a longer clamping bolt as needed.
What type of FD are you using?
01-04-13, 07:58 AM
I got curious and measured a coke can. .1 mm or .004 inches. Sounds like it's too skinny for your project. Real shim stock would be better here.
01-04-13, 08:09 AM
Scotch tape probably won't work unless it's built up to many layers. I've had good luck using a paint on layer, or two, of liquid plastic. Plastidip. More to protect the paint than build up thickness but the stuff is quite thick and could work for you if a few coats are used.
Oh, and, if Tom's kind offer turns out to be too thin for you, lemme know. I have shim stock in several thicknesses and could cut you a piece. Mine is brass.
Thanks for the offer, rootboy, I'll keep it in mind.
Pastor, I'm hoping to use a Shimano Tiagra on my son-in-law's SS, but I've yet to find a clamp-on in my size. For my orange SS I've collected a group of Suntour Sprint stuff, but have the same problem.
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