Tom,
Regarding the steerer for the 753 tubeset. I was Reynolds 531 (in
otherwords not heat treated), but it was a "straight gauge" steerer,
as in not butted and therefore thicker at the bottom. The result is
obviously a lighter steerer that wan not butted. Silver brazing
deffinitely reccommended.
There are most deffinitely 753 fork blades. And as Tom says, preraked.
The reason it was reccommended not to chrome 753 were two reasons;
first, heat from the polishing operation before chroming was
considered undesireable by Reynolds. Also, too much metal removal in
the same process was a potential problem as well. Like most any other
tubing, the reasons the material was to be handled in cetain ways was
to help insure longevity and non-failier of the material, for obvious
reasons. Columbus SL has always carried a specified weight limit of
the potential rider of a given frame to be about 70 kgs, as I recall.
I came out to about 154 lbs. Not that many manufacturers adheared to
that; how could they, other than limiting the frame sizes built with
each gauge of tubing. Custom builders have been (or should be)
carefully selecting tubing for each specific project, one tube at a
time.
Anyway, there are lots of ins and outs of all the types of tubing.
Much of what circulates as "facts and whatnot" amongst the general
public is rubbish. Although material is important to some degree; you
can trust me when I say that how the frame is built is more
important. The kicker there, contrary to what most framebuilders and
people in "the business" say, is that building a "good" frame is
extremely easy to do. What goes on inside most of what we all
consider "the cream of the crop" and "world class" vintage steel
frames from the classic era are far from perfect from a technical
sense. Poor mitering, really poor penitration, and numerous
other "major sins" in framebuilding are present aplenty in almost
every one of our revered classics. But they hold together, they ride
fine, and they will continue to do so for several more generations
most likely. So why build a bike to extreme precision and obcess over
every tiny detail if robots can build nearly perfect bikes? This
whole thing has captured my attention for quite a while now. I think
I'm getting close to putting it all in some sort of perspective that
has relevance and makes sense (oh no, PLEASE not that!!). Soon it may
be time to reveal that the Emperor has no clothes. Yikes!
Brian Baylis
La Mesa, CA
Where did this notion of the non-existance of 753 blades come from?
One listmember recently noted that his frame included a fork decal
marked "753 fork blades" or some such. Wouldn't such a sticker be a
little odd of no such blade existed?
As I recall a lot of fuss was made about the special 753 frok
blades, because they were only available pre-raked from Reynolds.
Only certain offsets were available. My understanding was that the
blades were raked, then heat treated, and couldn't be altered after
that. This was one of the more oft-noted tidbits regarding 753. And
yes, the steerers were all 531, as noted earlier.
Other 753 tidits that were widely discussed in the day:
You can't chrome it (though it can actually be chromed w/o problem
according to folks who would know).
"Silver solder only" though this assertion has been questioned on
this list, as has the relevance of the term "silver solder"
It can't be cold set (either after brazing or crash damage). I
assume this is more or less true, but I'm not a frame builder, not
even close.
You need to pass "the 753 test." This, I assume, arose from the
previous two issues. That is, bad brazing (overheating) was a
bigger issue because of the heat treatment, and bad alignment could
not be corrected by cold setting. Also, it was said that the
tolerances on the joints needed to be tight b/s silver doesn't fill
big gaps.
Pretty much just barfing up what I recall about 753 here, but for
ceratin there was much talk about the special blades. Man, that 753
stuff was the most ultra-super-de-duper exotic tubing at one time.
Tom Dalton Bethlehem, PA, USA
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