Framebuilders - repairing a front derailleur braze on mount

I asked this in the road forum, but figure you guys may be a better source. The braze on mount broke on my TT bike. Due to the shape of the tube, a clamp is not an option.

Anybody know where I can find a new mount to either rivet, or weld on? Only one I've found is haped for a curved tube, and the surface that this will attach to is essentially flat.

Also any thoughts on welding to Boron Carbide Ceramic Metal Matrix?


http://i72.photobucket.com/albums/i165/bobstewart/brokencloseup.jpg
http://i72.photobucket.com/albums/i165/bobstewart/broken.jpg
http://i72.photobucket.com/albums/i165/bobstewart/brokenfront.jpg

Point one would be whether this thing was heat treated after welding, because replicating that will be a nightmare.

Making an appropriate bracket would be pretty easy. It may be possible to simply stick a curved bracket into a vise or press and flatten the curve out of it. With steel, it is possible to heat it to sub orange and bend is. As long as it cools slowly, and the process is relatively quick there won't be any adverse effects.

If you want to restore it, but don't end up with a reasonable welding alternative. You could make up a little bracket out of an aluminum T extrusion and epoxy it on. Lots of surface area on the bracket is key. I would also get some glass roving/tow and wrap that down with more epoxy. That would be a lot like a clamp. It might take some angles to get it in the right plane, so without machine tools, you could cut it out of Al with a hacksaw.

Have you tried contacting Griffen to see if they can fix it?

Have you tried contacting Griffen to see if they can fix it?

yep. They are apparently Out of business. Reached a woman at one email address, and phone number that said she was no longer with the Company, and emails and was unsure of their status. Emails to the main address went unanswered.

I saw a Look frame at Branford bikes on Saturday and they had a riveted braze on mount that seemed to have an almost flat mounting. There were 4 rivet spots and it would appear with carefull cutting and filing that it would work for you problem. Now the real problem is does Look sell them to the general public. Worth trying I think.

This guy makes custom motorcycle parts. Does great work with good service. He could cut the piece out of steel for you.

Fabricator Kevin http://www.fabkevin.com/home.htm

You should be able to find someone locally to weld it. I'd personally talk to KendallF (he may know someone who is a good welder) or talk to:

Mild to Wild Custom Fabrication, Inc.
2487 County Road 220 Ste 101
Middleburg, FL 32068


I've seen some of his work, motorcycle and cars, but have never used him.

Andy

I'd say a steel bracket with a relatively large surface area where it meets the seat tube. 4-5 steel mandrel rivets and Hysol adhesive to hold it. If the right guy was doing the work, it'd look pretty good.