I was doing some
internet searching in relation to a bike I had to work on for the
Springhill Cycle Collection. The bike, an early 1970s model, had been stored in less than
ideal conditions and the alloy components were showing signs of
surface corrosion - not been cleaned before it was stored. The components were a Spanish copy of Campagnolo
and in parody of the great Roman cycling god, the copies were named
after the ruler of the Greek Olympian gods, Zeus. Frank Berto in his
tome 'The Dancing Chain' doesn't rate Zeus components. Zeus
components were never very common in this part of 'the oul sod', so
to get a bike equipped with Zeus is unusual. The bike is local, has
been ridden and used judging by the layers of dirt and wear to the
parts. Anyway to return to the point, the large flange hubs are not
Zeus and turned out to be of Japanese origin. I haven't seen photos
of this particular model of hub on the web.
However, here at
Methuselah Towers I have a confession to make. I haven't bought a
news stand cycle magazine in 10 years and don't frequent internet
forums, so therefore cannot claim any kind of expertise other than
experience. So I have to defer to the 'experts' on the web, who
advocate using various grades of abrasive papers and buffing wheels
to polish alloy components. Personally I would have grave
reservations about such an aggressive approach, as I have experience
of alloy components such as Campagnolo and Stronglight cracking and
failing. I also don't agree with re-polishing old alloy to a very
high surface shine, far removed from the original finish. To me it
detracts from the originality of the parts/machine and can, in my
humble opinion, be a case of 'over egging the pudding'.
I prefer a more
subtle approach, one advocated by a long forgotten source. I was
told to use a brass brush to clean alloy and then wipe the surface
with oil. I now prefer to use WD40 or an equivalent solvent, on a soft
cloth or a bit of kitchen roll, to wipe the burnished alloy. The
brush will get rid of the surface bloom and expose the nature and
extent of any surface pitting and corrosion. A decision can then be
made about re-polishing if deemed necessary. It is surprising how
much the brass brush will clean up the alloy, whilst still leaving a
sympathetic finish to the metal. Where the corrosion is not too deep
it can be polished out after cleaning, using Autosol and a soft cloth. A final clean
with a silicone based car polish will give it the final seal as you
have in all likelihood removed the original anodised finish. I have
tried to show a few before and after photos to illustrate the point. The Maillard small
flange hubs are ones I rescued from the scrap bin of a cycle
business.
Remember that you
will need to keep an eye on your repolished alloy as it will now be
more susceptible to corrosion as the anodised coating has been
removed!
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