Re: [CR] Definition of Bilaminates & Explanation

Example: Production Builders:Cinelli:Laser

From: "Mick Butler" <>
Subject: Re: [CR] Definition of Bilaminates & Explanation
Date: Sat, 22 May 2004 20:50:44 +0000

Richard Sachs, Asked the following below. Well lets put it all into some sort of historical context. Harry (spanner) Rensch started building around the 1935 mark. He first visited the Paris show in 1935 and came back with two ideas that he saw there. First the idea of welded frame construction as used by the cycles in the Tour de France and secondly the idea for the Galibier. The 35 show exhibited a Jaques Schultz machine which is very similar in looks to the Paris Galibier. As soon as Harry returned he pioneered the welded frame in Great Britain and was up and running by 1936 with welded frames. By 1938 Rensch production output was about 45% welded and 55% brazed. References 38 & 39 Rensch catalogues, 40s & 50's Accles & Pollock Kromo tubing adverts in the British Cycling Press. Claud Butler not to be out done by a competitor started experimenting with welded frames in 1937 and exhibited their first welded model the "Massed Start" at the 1938 earls Court Cycle Show. Incidentally this was the first model to be fitted with the new CB rear fork end, they later called this the CB Continental end. Reference The Cyclist's November 9the. 1938. As I said previously in my CR postings Claud and Harry were the UK pioneers in welded frame construction. Welded frames also coincided with the "New Look". Prior to the Second world War the fashion began to change to Continental and short wheel based machines. This SWB craze went to extremes with frames being built with angles so steep as to be uncomfortable and sometimes dangerous. Frame breakages were not that uncommon and invariably these machines were of lugless welded construction. You could'nt make lugged frames with these angles, they did'nt make cast lugs with these angles. This inevitably gave welded frames a bad name. Reference The Bicycle November 17the. 1948 article by Johnnie Dennis. In this same article it says "Back in 38 the welded frame was a novelty a innovation from the Continent and only two of the more ambitious lightweight firms were using the welded method. The introduction and popularity of welding was hardly established before some manufactures decided to explore further into the field of jointing tubes (Paris first & Butler's 2nd.) Various methods, which incorporate a mixture of welding and brazing, soon took to the market. Paris's produced a model using this idea- and soon after Claud Butler introduced his popular "Bi-Laminated" construction. Claud coined the phrase. Others followed suit Dayton with Amalgam and Royal Enfield with Unitized which were two other popular welded frames. So where are we now. Yes welded frames got a bad name but not necessary Paris or Butlers. Did they use bilaminates to make their frames look lugged yes indeed. Does a bilaminate add strength I doubt it but you really need a builders opinion on this one. Why use bilaminates obvious to build a frame with steep angles so that it has the appearance of a lugged made frame. Not only that some of us think they look cool, not unlike the American taste for Cadillac's and Plymouths with enormous shark fins and chromium embellishments. Not to my taste. Finally I have tried my hardest to back this up with historical references. Now I am getting bored with this one.

Best wishes and be lucky. Michael Butler Huntingdon UK.

>From: Richard M Sachs <>
>Subject: Re: [CR] Definition of Bilaminates
>Date: Sat, 22 May 2004 14:59:11 -0400
>well, thanks mick -
>just for the record, i think the discussion has centered
>around the definition of bi-lams being adornments-cum-
>reinforcements that were added to a fillet brazed joint
>to give it a faux lug appearance. imr, that's how this began.
>now - i'm not a history buff, so i will ask: did the builders of
>bronze welded frames in gb add these to their frames to
>create the illusion that it was a lug-ish joint because they
>didn't want to leave "just the fillet", or did they add them
>under the assumption that a fillet-ed joint wasn't strong
>enough and the bi-lams would bring it up to spec?
>chester, ct