Steve;
If I am understanding your description of the problem correctly, this may help (it did with my Mafac Racers). The brake shoe holder post goes th ru a hole in the retaining bolt at the end of the brake arm. When the nut is tightened, the post comes to rest on a thick alloy washer which in turn rest s on the brake arm. Since the post is round and the washer flat, you have only two tiny points of contact there which, in my experience, can sometimes allow for bot h slippage and excess vibration (which may be a source of squealing).
Get a round file that is the same diameter at the brake shoe holder post (I believe a chainsaw sharpening file may work) and file a groove across the fa ce of the washer to accomodate the post's curved contour and provide much great er contact area. That should solve your problem. If you like, you can als o file this groove at a slight angle (a bit deeper on one side) to apply a lit tle toe-in to your pads.
Bob Hovey Columbus, GA
In a message dated 5/30/06 11:06:00 AM, Steve writes:
>
> Date: Tue, 30 May 2006 10:23:45 -0500
> From: Steve Leitgen <sleitgen@charter.net>
> To: Marty Eison <meison01@gmail.com>
> Cc: classicrendezvous@bikelist.org
> Subject: [CR]Mafac Brakes #%&$#^!!!!
> Message-ID: <7E1DEBB1-625D-423D-B81B-BE73600E864E@charter.net>
> In-Reply-To: <7d49b7530605231231l718420cci234d3f44f4038ada@mail.gmail.com>
> References: <7d49b7530605231231l718420cci234d3f44f4038ada@mail.gmail.com>
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>
> Mafac brakes! Were they a mistake or did they do it to us on purpose!!!!
>
> I'm having problems keeping the post on my Mafac (comps) brake pads
> from slipping when braking. One hard brake too many and they compress
> giving less than optional braking. (Imagine squeeling like a little
> girl and going to the Flintstone's) Yes, I tightened the bolts.
>
> Any helpful hints out there in CR land?
>
> Steve Leitgen
> La Crosse, WI