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Voyage of Columbus: Inside the Italian steel giant

Peter Stuart
28 Jul 2016

For fine Italian steel bikes only Columbus tubing will do. But the company is as much about modern technology as artisan craftsmanship.

As I walk into Columbus HQ, just outside Milan and 45km south of the Eastern Alps, I encounter an enormous canvas. It’s a painting of a high-rise apartment building saturated in the red light of sunrise. A sleeping woman lies in the foreground and in the background a man leaps, arms spread like wings, from the balcony. 

It’s all rather fanciful and surreal, and I wonder if I’m in the right place. I expected the headquarters of a company that specialises in metal tubing to be stark and industrial, but I’m soon to discover that the world of steel is a surprisingly complex and beguiling realm. 

‘Steel is like water,’ says Paolo Erzegovesi, CEO of Columbus. ‘The rules are exactly the same rules that we have to consider when water moves in the tube or channel. It’s a fluid.’ 

Erzegovesi is doing his best to explain the company’s intriguing manipulation of steel – processes that take raw unfinished tubes and refine them for framebuilders to turn into top tubes, down tubes, stays, head tubes and other frame parts in everything from the entry level to the highest tier of custom bespoke bicycles.

At one machine, I watch as a short steel tube with a rough chalky finish is pushed through a circular die. What emerges out of the other side appears to be an entirely new material. It’s now mirror-smooth, black and nearly twice as long. It has a greater internal diameter, thinner walls and a new exterior finish, all without one degree of heat applied – using just pressure. This ‘cold drawing’ creates new shapes and dimensions, but is also used to butt the tubes, creating a variable wall thickness from end to centre.

Machines such as this haven’t changed much in decades, but the steel itself has evolved at an astounding rate in recent years, as scientists have created new alloys with properties almost unrecognisable to the steel of the ‘golden age’. 

Forge of ages

For Columbus it all began in 1919, when Angelo Luigi Colombo opened a small factory to produce steel for any and all applications. Bikes were all the rage, especially in Italy, so Colombo’s first customers were the likes of Bianchi, Maino and Umberto Dei, all masters of classic Italian steel frames. After flirting with automotive and aeronautical parts, Colombo founded Columbus tubing and discovered a niche in designer furniture in the early 1930s.

‘We have a small collection, not properly structured but an interesting character in the history of the brand,’ says Federico Stanzani, my guide for the day as we walk through a cluster of antique modernist furniture. ‘In the late 1930s and 40s, Columbus provided tubes for Italian and European designers like Thonet and Marcel Breuer.’ As fashions and materials changed, though, Columbus found demand tailing off. ‘We stopped producing them because the industry moved to cheaper tubes. A few furniture designers still use our tubes, though. Max Lipsey recently produced some very unique coffee tables using Columbus tubing.’

Either way, furniture’s loss turned out to be cycling’s gain. Columbus tubes have been ridden to victory in the Tour de France by such cycling legends as Eddy Merckx, Bernard Hinault, Fausto Coppi, Jacques Anquetil and Greg LeMond.

And while one tube may seem much like the next from the outside, Columbus has delivered plenty of innovation, and some experimental and truly off-the-wall tubesets, over the years. The Cinelli Laser Strada, for instance, was a landmark steel frame design with streamlined aerodynamically shaped Columbus steel tubing – kind of like a Cervélo S5 for the mid-1980s.

Yet it’s below the surface where the most lasting changes have taken place. Once upon a time Columbus championed Cyclex steel, a basic derivation of the extremely popular chromoly alloy. Then in 1986 it developed Nivacrom steel tubing. This used vanadium and niobium as alloying agents to help increase the strength-to-weight ratio of the tubes. 

‘When we developed Nivacrom we went from a steel with the mechanical strength of 85ksi (kilopounds per square inch) to 130ksi,’ says Erzegovesi. Since then the brand has developed Niobium. ‘As we increased the grain of our alloys they became more brittle, so we used small additions of niobium and vanadium to make the new shapes and strengths possible.’

Above Niobium sits XCr, a stainless steel similar to that developed for Reynolds 953. And it’s that top end of Columbus’s range that’s now most likely to find its way onto a bicycle frame. Where chromoly was once the choice of mass production, Columbus has focused on the booming world of high-end bespoke frames. With new steels come new challenges, as well as new opportunities, in butting and finishing the tubes, which is where the real artistry lies.

Metal magic

‘We start with a French company to smelt and cut the original tubes. Then an Italian company drills the mandrel and others work on the heat treatment to provide the directional stiffness. We do the final step, which is butting and shaping of the tube,’ Stanzani tells me.

That may seem like a small step in the overall process, but look around the factory floor and it becomes clear that this final butting process involves a whole world of complexity.

‘All of our tubes are seamless, except Cromor,’ Stanzani says. ‘The tube is produced from a billet and then step-by-step extruded [a cavity is made in the centre to create a tube]. We get the raw material as a 6m-long tube without a seam. This offers much better mechanical characteristics.’ The hole is extruded using a process called lamination and perforation. It’s done at extremely high temperatures of 1,450°C and involves rotating the tube from both ends to create a hole at the centre, like rolling dough or pasta. ‘You start with a one-metre billet, which becomes a two-metre hollow bar,’ says Stanzani.

Once in tube form, with an extruded hole, the steel can then be manipulated. Here on the factory floor, a team of veteran Italian metalworkers (many of whom have banked 20 years or more with Columbus) takes all manner of different tubes through a variety of processes.

We walk over to one machine that currently has a set of fork legs mounted to it. Once a technician has carefully positioned the tube, the machine stamps it into a neatly curved fork with an elegant effortlessness that is altogether surreal when considering the forces a fork is capable of resisting. Here it bends like clay.

‘This is the jewel of the crown, together with lamination,’ says Stanzani, pointing to the cold drawing tool we began with. It looks like a giant cannon. ‘This mandrel [the cylinder the tube is mounted to] has a variable thickness. At the edges the diameter will be smaller to enable a thicker wall section of the tube – butting it.’

Butting, another process that traces its origins back to the end of the 19th century, is a key part of Columbus’s work, as it reduces weight while preserving strength and stiffness. 

The die itself is only minutely different in dimension to the tube that passes through it, but different enough to completely change its form. In years past this die would have been made of super-hardened steel and would itself be subject to deformation through repeated use. New dies are ceramic, which broadens the range of tubes that Columbus can work with, opening the door to harder steels. Cleanliness remains key to the accuracy of the process, however. ‘One grain of sand could compromise the performance of the tubes,’ Stanzani notes.

Surprisingly, one pass through a cold drawing process is not enough to finish a tube. ‘Usually we start from a minimum of seven passes of cold drawing to a maximum of 15,’ says Erzegovesi. Some passes alter the tube width, others control the butting or diameter, but manipulating the material so significantly can compromise the integral nature of the metal itself. 

‘You have to make a hot process in the oven to recreate the structure,’ Erzegovesi (an engineer by trade) says. ‘Because metal is a crystal, the crystal changes shape and becomes more and more brittle.’ That means after numerous runs through the cold drawing process, and as much as a 65% reduction in thickness, the steel must then return for a stint in the oven – a process known as heat treating or annealing. There it will sit until the crystals within the steel have regained some of their original structure. 

Alongside cold drawing is cold lamination, to further butt or taper the tubes. ‘The tube passes through a machine with two rotating rollers squeezing the external skin of the tube against the internal mandrel. With that you can control the inner diameter and the outer diameter. You can also manipulate the length,’ Erzegovesi says.

These processes mean big forward steps are possible as the steel alloy technology itself has moved on, facilitating developments such as Columbus’s super-wide 44mm tubes. 

Steel horizon

‘There is still a lot of development in steel,’ Erzegovesi argues. ‘Yes, maybe there are relatively few companies looking into this – us and maybe Reynolds. But of course steel is still being developed by other applications, such as the automotive and aeronautical industries.’

This broader development of steel has brought about some interesting developments. ‘XCr is a recent example of this,’ he adds. ‘Stainless steel was developed by French steel makers and the original purpose was as a material suitable for the armour of battle ships.’

Converting the technology into a form compatible with bike-building was no easy task, but the demand was there from high-end framebuilders, specifically Dario Pegoretti in this case. ‘When we approached this, the XCr stainless steel was only available in the form of plates, but we needed tubes so we had to set up a new technology to extract a tube, which was really expensive,’ Erzegovesi says.

R&D is still central to Columbus’s work, as the brand continues to update the steel alloys it uses. ‘I personally follow 36 young engineers’ degrees,’ Erzegovesi tells me. ‘Fabrizio [Columbus’s vice president] follows between 15 and 18, I believe. Usually we fund a student’s final thesis if they choose a subject that involves the bicycle. A recent one was a student developing a machine for testing vibration and the transmission of signals from the road.’

For Columbus, the increasing focus on integration and mass production, rather than the highly personal and ever-evolving benefits of making custom steel, means the industry has been moving in the wrong direction. ‘I’m totally against the idea of fixed geometry,’ Erzegovesi says. ‘Geometry is one of the most important factors in bike performance and enjoyment. The problem is the industry. With £300 worth of steel tubes you could make a beautiful bespoke bicycle, with no barriers to innovative design, good geometry, a good paintjob and everything. If you make an investment for a new carbon frame the moulds cost £150,000 so you have to stay with a fixed shape. The industry invented the slope geometry so that one size fits all.’

We’re sitting for a late lunch, and Erzegovesi is sketching the stress-strain curve of a steel tube on my napkin, breaking only to criticise the direction of the industry. He’s trying to explain, as simply as possible, why Columbus has been able to develop wider, thinner tube sections.

‘You’re going to miss your flight,’ Stanzani warns me. With a dismissive hand gesture, Erzegovesi shrugs off the suggestion: ‘It does not matter.’ He points to a set of wild scrawls between his strain-stress curve and a crude diagram of a frame. ‘Our new materials are more stable, while the technology to draw the tubing is a lot better. That’s why we can create wider and stiffer tubes. We’re always working on new steel – new alloys.’

That might be a hint at what’s to come, but for Columbus it isn’t just about creating the stiffest and lightest tubes conceivable, but ensuring its steel can be worked with. ‘The problem is you have to consider how different builders will use the steel. Some producers offer heat-treated tubing that is super-strong and hard, but it’s only possible to cut with electro-erosion. This isn’t something for a framebuilder – it requires heavy industry. And for all the extra strength of the tube, the weld is put under more stress.’

With that he hands me my napkin sketch, which I fold neatly into a pocket, and we rush out of the building for Milan. Driving away we get one last glimpse of the factory, and a four-metre tall giant that guards the main doors.

It’s an Aztec-like painting of a body, filled with intricate doodles and patterns, from which the tubes of a bicycle spurt out like arteries – the work of street artist Z10 Ziegler, commissioned by Columbus. It seems like a grand and avante-garde figure to be guarding a warehouse of steel tubes, but it’s a reminder that there’s something beautiful and almost mystical about steel.

After 120 years, steel is still capable of juggling the romance of a classic bike with the cutting edge of bespoke design. Carbon may be the popular choice in the mass market, but at Columbus steel is still real.

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