Norris,
Years ago, while doing some aircraft and race car welding, I
performed a bit of work on straight gauge chrome-moly tubing.
Occasionally, we would use tubing with wall thickness of about
1mm. You must use a _really_ small tip on the torch and be
very careful about heat buildup.
Now, my work was merely acceptable, but I did see some real
masters are work. Still, I never saw work that was so fine as
to be mistaken for fillet brazing. In fact, for me, that's
almost unimaginable. For one thing, you have to work in
sections and - in the work I saw - the points where these
sections met had obvious overlapping of welding beads. (On my
own work these were prominent, andI was happy not t oburn
through the tubes.) Also, you must start in the "crotch" of
the joints and work outwards. Since this was done in opposite
directions, there always was some small but obvious overlapping
joint, even in the work of the masters.
But you probably already know all this. So I guess what I'm
saying is that I've seen some nice work on fusion welded
chrome-moly tubing. But I've never seen anything as fine as
the work you describe. It's actually difficult to imagine how
he managed to perform such aesthically perfect work in the
bottom bracket area.
Surely you're thinking that it's almost a shame to cover
this work with paint.
Best regards,
Fred Rednor - Arlington, Virginia (USA)
> During the short period between returning from France in
> mid-August and
> going back next week, I have found it difficult to settle
> down to a real
> job of work, so I decided to take stock, so to speak, of some
> of my
> ever-expanding stock of bikes and frames.
>
> Having spent some time checking over a couple of Bernard
> Carre-built
> Sauvage-Lejeunes, once the property of Henri Anglade and
> Bernard Guyot,
> I thought it about time to inspect some of my older
> properties...and a
> trio of 1920/30s machines came to mind.
>
> The first is a 1920s Automoto, claimed to have been a team
> machine but I
> have no way of proving its provenance, the second is a 1935
> Alcyon
> ex-team bike, and the third one, my only fully-built-up
> Reyhand
> Randonneur, the work of the genius framebuilder, Paul Reiss.
>
> I have been corresponding with List member Mike Kone about
> this one, and
> sending photos of the two decals on the frame, as Mike has
> the means of
> reprinting some decals that I might need...With an
> "old-timer" such as
> this Reyhand, which was a "barn-find" it is always a
> difficult matter
> whether to renovate or not, Sure the frame on this bike has
> oodles of
> patina..that is when I removed the caked on road dirt.
> Luckily there is
> no rust whatsoever, but in places the chocolate brown enamel
> has either
> been rubbed or scratched off, exposing the coat of red-oxide
> undercoat
> clinging to the steel tubes.
>
> I was curious about the condition of the drive-side chainstay
> which
> seemed to show the effects of time more than any other tube,
> so I
> decided to remove a flake of paint just about managing to
> hang on to the
> rear drop-out. Having dislodged it I decided to rub the
> drop-out
> -to-stay junction with some fine wet-and-dry paper to smooth
> in the
> junction of paint and exposed steel. So...I know that all
> this is
> sacriligeous... but I needed to know.
>
> The joint at this point is beautifully profiled..the sort of
> thing that
> frame-builders love to shape and form and polish, burnishing
> the
> silicon-bronze to a high shine. But...there was no sign of
> bronze
> here...just shiney grey steel! My curiosity got the better of
> me. so I
> polished away at the underside of the junction of the
> chainstay with
> the bottom bracket shell. thinking that, if needs be, this
> small area
> would be easy to touch up. No bronze here either, just plain
> polished
> steel...as I concluded the rest of the frames joints must be.
> So it
> appears that Reiss fusion -welded not bronze-welded his
> frames. Some
> real craftsmanship here!!
>
> I didn't let my eagerness get the better of me and stopped
> rubbing and
> exploring at that point... I have owned, examined and built a
> lot..a
> real lot..of lugless frames, and everyone has been joined
> either with
> nickel bronze or more commonly with silicon bronze, the
> fillets being
> finely radiused to produce a sculptured stress-relieving
> finish.
>
> I know that the 1920s Automoto is fusion welded ie
> steel-to-steel, but I
> never even considered that the Reyhand might be..it was
> always, in my
> mind, a bronze-welded (fillet brazed) structure.
>
> The Reyhand has been completely dismantled down to separating
> frame from
> fork, with only the fixed B/B cup and the upper and lower
> head bearing
> cups in place.
>
> The frame is a 24" Durifort-tubed randonneur with a large
> built-in
> pannier rack, and stacks of braze-ons for dynamo, brakes etc
> etc. and
> yet it weighs only 4.25lbs. The fork..with its robust
> twin-plate crown
> and everlastingly long fork blades tips the scales at
> 1.25lbs...making a
> total weight for the ensemble of 5.5lbs.. Absolutely
> astonishing !!!
>
> The weight of the frame leads me to assume that the tubes are
> of very
> thin gauge..they are double-butted. So...the question that I
> ask myself
> is...just how amazingly skilful does a builder have to be to
>
> fusion-weld fine gauge tubes..possibly as fine as 0.9, to a
> thick bottom
> bracket shell without "holing" the finer pieces?
>
> This is a process that I have never tried when building a
> frame..and
> even though I would feel quite adequately skilled enough to
> fusion-weld
> up a frame in plain-gauge "gas-pipe" I think I would decline
> the
> invitation to try my skills on any tubes as fine as those on
> my Reyhand.
>
> Has anyone on the List come across similar types of
> construction on a
> quality frame..or have any of the List's frame-builders
> risked their
> reputations carrying out this type of construction?
>
> Norris Lockley..Settle UK
>
>
>
>
> _______________________________________________
>
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