Fred,
I have no reason to doubt that there were delamination occurrences inasmuch as I have read the rare first hand accounts of others some of whom I know well enough, if only by reputation, to hold in high esteem with respect to their cycling experiences. But for me, the question remains: WHY did it happen?
Back when I first became aware of their existence in 1976, I affixed a set of these Scott / Mathauser finned and curved brake shoes and pads onto my 1973 Gitane Tour de France whose MAFAC Competition calipers had already been outfitted with a homemade brake bridge or "booster". I did so because I was keenly aware of how important those brakes were to my health, well being, and general competitiveness (...regardless of that old Tazio Nuvolari, renown former world champion race car driver, story wherein he supposedly said after winning the 1935 German Gran Prix in an obsolete Alfa Romeo whose brakes had failed half way through the event, "...why would I need brakes? All they do is slow me down."). At the time, I did not have the luxury of a "dedicated" race bike and so my trusty TdF had to do double duty as both my weekend warrior and regular mode of transport - which meant that not only did I abuse my brakes in competition but I furthermore subjected them to the regular rigors of riding from my parents' house in Healy Heights at the top of Council Crest to downtown Portland, Oregon - a 1073 foot vertical incline or drop depending upon your direction in just under 3 miles (...that would be an average 7 percent grade with some portions significantly steeper because there are a few flats along the way, believe it or not). The result is that I smoked every other type of pad that I tried until I found these Mathauser's. Subsequent to their use, I never once encountered any problem with stopping power or undue pad wear, and certainly not anything along the lines of delamination. They out performed anything else I could find regardless of wet or dry weather conditions. Not only was I completely thrilled with their performance, I did not once hear anything other than glowing praise for same from any of my contemporaries who also used them.
Fast forward a couple of decades during which time I ended my remarkably unaccomplished racing endeavors, got married, finished my "gradual" studies, embarked upon a career, undertook a much more casual attitude with respect to the whole cycling scene, remanded my saddle time to occasional but enjoyable rides in an around the Puget Sound where I was then living, before finally getting lured into competing in my first triathlon event wherein my interest in cycling was immediately rekindled. It was only then, after I had begun poking my nose about the various internet velo related sites (...and now their ephemeral cousins, the cycling blog) that I first saw or heard mention of any potential for those early Scott / Mathauser brake shoes and pads to delaminate with possibly disastrous results. So, you will have to excuse me to the extent that I would seem to be stuck in an apparently outmoded paradigm such that when you reference them in conjunction with the phrase "...tarnished reputation", I have to ask myself, "...what the heck is going on and where was I when all of this came about?". All I can tell you is that these bits were held in high esteem back when they were de rigeur among the serious cycling crowd in my corner of the world. Which brings me back to my question of WHY it is that these brake shoes and pads are supposedly considered to be failure prone and is this reputation begot of a statistically significant number of occurrences or merely a few rare instances that have been recounted over and over ad nauseam to an ever increasing audience courtesy of the world wide web (...i.e. hearsay, internet urban legend, revisionist history, hoodoo voodoo, B.S., or reality)? And for those who can speak from personal experience, WHY do you believe that your particular shoe and pad combination failed? I truly want to know. Indeed, to the extent that one is able to clearly identify with distinction or even opine with some degree of deductive logic the rationale for such failure, it stands to reason that your insights would be of immense benefit in the form of potential preventative precautions for those who may still wish to employ these older Scott / Mathauser products.
Robert "...not from Missouri, but sure like their motto" Broderick ...the "Frozen Flatlands" of South Dakota
------------------------------------------------------------------------------------------------
>From: Fred Rafael Rednor <fred_rednor@yahoo.com>
>To: classicrendezvous@bikelist.org
>Subject: RE: [CR]A Few More Vintage Parts For Sale - Mathauser Bonding
>Agent
>Date: Sat, 2 Sep 2006 20:15:49 -0700 (PDT)
>
>As is the case with many products with tarnished reputations,
>many people do not experience any problems at all. But - with
>the Mathauser finned pads - I have. It might not have occurred
>often. But I'm certain the people at Scott-Mathauser saw at
>least a few cases.
>
>When I contacted Scotty about my pads, he didn't seem at all
>surprised and also sent me a replacement set, which were of the
>more mundane type type that resembled MAFAC tandem brake pads,
>except of course that they were red in color.
>
>He also insisted I send him my old finned pads.
> Fred Rednor - Arlington, Virginia (USA)
>
>--- "R.S. Broderick" <rsb000@hotmail.com> wrote:
>
> > David,
> >
> > I sent an off-list reply directly to John with respect to his
> > earlier post
> > regarding my "editorial" on Scott / Mathauser curved and
> > finned brake shoes
> > having "permanently" bonded pads. The basic gist of that
> > communication was
> > that I have never personally experienced any delamination
> > problems where the
> > pads somehow broke loose from their holders (...and I abused
> > the living
> > daylights out of a set of these for a good number of years).
> > Whereas I may
> > have seen pictorial evidence of such delamination as well as
> > read the
> > accounts of others who have supposedly encountered it
> > personally, I have
> > still to this day never yet heard nor read a detailed
> > explanation as to how
> > and/or why this may have occurred (...age related fatigue of
> > the bonding
> > agent ... brittlization of same due to durable exposure to
> > temperatures of
> > extreme? ... exposure to significant contrasts in actual
> > temperature whether
> > it be ambient or friction based usage induced? ... a
> > manufacturing "flaw"
> > resulting from improper use or application of the bonding
> > agent? ... the
> > unfortunate result of someone actively trying to pry loose
> > the pad from its
> > holder thinking that it was of the "replaceable" type? ... a
> > combination of
> > any one or more of these factors? ... something else
> > altogether? ... if
> > anyone out can knowledgably speak to this question, please do
> > chime in here
> > as inquiring minds want to know).
> >
> > Moreover, I do not know for a fact what was used as the
> > original bonding
> > agent although I have read what I believe to be only the
> > conjecture of
> > others that it was some form of "Permabond", "Crazy Glue", or
> > other
> > cyanoacrylate adhesive. If, indeed, that is true, it would
> > be well worth
> > noting that there are several variations of this type of glue
> > (...and I am
> > not referring to brand names here) which are intended for use
> > on very
> > specific substrates. That is why I made the particular
> > recommendation in my
> > original "For Sale" posting with regard to the use of Loctite
> > Prism 406 -
> > because it is specifically engineered to adhere the materials
> > involved. To
> > quote from Loctite's own sales literature, this agent "...is
> > a low viscosity
> > adhesive ideal for difficult-to-bond rubber components and
> > pre-assembled
> > parts. Designed to penetrate by capillary action between
> > components."
> > Should you wish to review the technical data sheet on this
> > particular
> > product, you may do so using the following link:
> >
> > http://tds.loctite.com/
> >
> > Robert "occasionally accused of being stuck in the '70's"
> > Broderick
> > ...the "Frozen Flatlands" of South Dakota
> >
> >
>---------------------------------------------------------------------------------------
> >
> > >From: "dddd" <dddd@pacbell.net>
> > >To: "Classic Rendezvous" <classicrendezvous@bikelist.org>
> > >Subject: Re: [CR]A Few More Vintage Parts For Sale
> > >Date: Sat, 2 Sep 2006 18:14:12 -0700
> > >
> > >What was the original adhesive used to bond the pink
> > urethane pads to the
> > >aluminum "holders"? Urethane adhesive? Crazy glue?
> > >I've got one here that's starting to peel, I was hoping to
> > sand the
> > >surfaces and re-bond it, using appropriate care of course.
> > >
> > >David Snyder
> > >
> > >
> > >----- Original Message ----- From: "John Thompson"
> > ><JohnThompson@new.rr.com>
> > >Subject: Re: [CR]A Few More Vintage Parts For Sale
> > >
> > >
> > >>R.S. Broderick wrote:
> > >>
> > >>>CAUTION: as with all original Scott / Mathauser finned
> > and
> > >>>curved brake shoes and pads of this vintage, the brake
> > pads themselves
> > >>>have been permanently bonded to the aluminum shoes - how
> > "permanent"
> > >>>this bond may be after thirty years is a matter for
> > speculation
> > >>
> > >>FWIW, I've had several sets of these in regular use for ~25
> > years with
> > >>no signs of delamination, and very little thinning of the
> > pad material
> > >>either for that matter.
> > >>
> > >>--
> > >>John (john@os2.dhs.org)
> > >>Appleton WI USA
> > >
> > >_______________________________________________
> >
> >
> > _______________________________________________
> >
>
>
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