[Classicrendezvous] Re: Frame tubing

(Example: Framebuilding:Brazing Technique)

Date: Wed, 18 Oct 2000 16:23:10 +0100
From: "Hilary Stone" <Hilary.Stone@Tesco.net>
To: Jerry Moos <moos@penn.com>
CC: gregparker1 <GregParker1@compuserve.com>, "richard m. sachs" <richardsachs@juno.com>, classicrendezvous@bikelist.org
Subject: [Classicrendezvous] Re: Frame tubing

Columbus SLX was 0.9/0.6 for all three main tubes ­ I think there was a lighter incarnation in its last few years but I haven't got my catalogues to hand at present. Reynolds 531 C was normally 0.8/0.5 top tube and seat tube, 0.9/0.6 down tube, 531ST was 1/0.7 for all three main tubes but many sensible builders used thicker gauge tubes in the larger frame sizes with either tubeset to increase stiffness. Indeed Gazelle in Holland were so skilful at this that their frames increased in stiffness from small to large. Fiets magazine had a complete set of Gazelle frames tested for torsional and bottom bracket stiffness. The largest frames amazingly were the stiffest because of Gazelle's choice of tubes and the smallest the least stiff. I nearly had a major row with the editor as I had written that larger frames were normally less stiff than small ones. He hadn't realised what Gazelle had done. 753/653 had 0.7/0.5 top and seat tubes with with o.8/0.5 down tubes in the later versions ­ it was onlu the earlier versions that were much thinner. Tange Prestige Super Lite was a really scary 0.6/0.3 for top and down tubes with triple butted seat tube 0.7/0.4/0.6. Standard road Prestige was 0.7/0.4 top and down with triple butted 1/0.8/0.6 seat tube. Columbus SP was 1/0.7 throughout all three main tubes but many builders simply used a SP down tube particularly in larger frame sizes to increase stiffness and the tubing sticker will not reflect this. This sort of practice was very common amongst the better more thinking builders. TSX had 0.8/0.6 top and down tubes with a 0.9/0.6 seat tube. The top and down tubes in this set had five spiral ribs running the complete length and the seat tube five spiral ribs on the butt. SLX just had helical ribs on the butts. SPX was the same as SLX except for being 1/0.7 throughout the three main tubes. Tony Oliver's book Touring Cycles published by Crowood has a very complete table of tube specs which were current around 1985 to 1990. It is still in print and I rate this book as one of the very best at explaining the whys and wherefores of speccing frame tubing. ISBN number is 1-85223-339-7. It is a shame that it hasn't been revised though. Hilary Stone

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Jerry Moos wrote:

>


> Do you know the wall thicknesses of the other current Reynolds tubesets? Did
I understand someone to say that Columbus SL was 0.9/0.6/0.9? Anyone know
the
thickness of SLX or TSX? The Columbus site no longer lists them.