The Columbus Spirit tubing frame I built for James came back for a re-paint … after 45,000km of A-Grade Veteran road-racing and training in approximately 4 years! It’s a nice verification of the potential durability of the most delicate, i.e. thin-wall, frame tubing that Columbus offers. It is however only a sample-size of 1. I might regret this but ….. this bike has travelled 53,000km as of May 2015  

As with all frames that I construct, it has many small crafted details that make it more robust while adding very little weight. They take more time to do, can be fiddly to make happen but now that I fully understand their benefit, I will not compromise and take shortcuts. By eliminating the common weak spots, I can choose to use even more delicate frame tubing than I might have otherwise

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James going for it…..  

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Elegant, sensible frame design is way more than just the presence of pretty-welds** and on a frame with butted tubing, a discussion that only mentions the appearance of the welds really misses the point! I have some sympathy for those that broadcast that opinion, since due to the ‘craft’ nature of framebuilding, even my own understanding of the significance of butting and it’s true purpose was not fully-formed until a few years ago. 

If I tacked all the main tubes together and then welded the whole lot in one go, if I brazed in the bottle bosses after welding the main tubes, if I did not reinforce the “seat cluster” then this frame would be far less robust and would not last as long. That is proven by examining carefully frames that do fail. A good welder may well be able to TIG-weld a “standard” thin-wall seat-tube but that’s not smart framebuilding because a careful study of what endures and what fails prematurely makes it clear that increased wall-thickness is necessary there. The short-cut methods I have mentioned here are just some of those used by most large framebuilders to speed up their work and unfortunately also by many of the small framebuilders new to this craft. I will not take shortcuts in my work and I continually strive to improve.

I have only learnt this by having done frame repairs, which I do on only a limited basis now. A frame CAN be lightweight, of an adequate but not crazily excessive stiffness, robust, good value and also have a nice forgiving characteristic way of failing should the frame be overloaded, e.g. when overloaded by an impact. My frames balance all these competing requirements in what I consider to be the best balance. Sadly, so much of the quirky, eye-catching, curvy-tube, minimalist rear dropout, flat-plate chainstays around fat-bike tyre designs that are the current eye-candy of the web are just plain bad design and compromise robustness enormously. They must either use thicker wall tubing with a big weight penalty, or they will simply fail prematurely. Such as the rear dropouts with huge windows, sharp edges or spindly spans of solid steel.

I’ve made only three Columbus Spirit frames so far because of the delicacy of the tubing and the slightly ridiculous stiffness a Spirit frame will have with its large (for a steel frame) downtube. While this frame is of course a sample size of only one, it is a great example of what is possible. I was also able to repair a significant dent under the downtube created by a rock thrown up during a race and with a new coat of paint this frame rolls onward. Because of the forgiving way in which steel frames behave should they begin to fail, I was able to tell James that he could keep riding the bike if he made regular checks of the dent before he could get it to me for repair. 

 

** On a frame made of plain-gauge, i.e. constant-wall-thickness tubing you need pretty, uniform welds. Butting was developed in 1895 (I’m not joking!) for durability not weight-saving. It was developed to fix the problem of poor durability of the joints at the ends of bicycle frame tubes which at the time had a constant wall thickness. Frames were developing fatigue related cracks at the welds, far earlier than might be expected. Butting, which thickens the tubing walls slightly at the ends to buttress the joint is a REALLY elegant solution to that problem. The highest material stress is shifted away from the weld to the tapering section of the butt if it is located appropriately. If the main frame tubes don’t use butted tubing then the welds need to be pretty and uniform because that is what is holding-off a fatigue crack from developing prematurely. The use of plain-gauge tubing in whatever frame material you care to name has been really poor design since 1895. There is an obsession with uniform welds these days on titanium (Ti) frames, ninety five percent of which are made from non-butted tubing. Ti’s properties are not magical so it can not defy this very old and very real problem. In terms of elegant design, a steel frame made of butted tubing makes a titanium frame look incomplete and over-hyped. Ti material is slightly more damped than alloyed-steel and can weigh a small amount less, but only butted Ti frames compare to mine for elegant design. Ti frames can and do crack.