Inside the steel bicycle
Many people today have rediscovered the world of steel bikes, their qualities and what they have to offer.
Steel bikes have always been around, in deep the majority of restored vintage and classic bicycles are made of this material, and even century-old bikes can still be used today.
The emergence of new composites, combined with a culture that increasingly accepts product obsolescence, has somewhat eclipsed the noble material of steel.
The evolution of the steel industry over the years has created alloys that are fatigue resistant, flexible and lightweight.
The great secret of these qualities lies in their compositions, their hot or cold forming and their structural design.
The best known brands currently supplying material to manufacturers are:
Reynolds (England), Columbus (Italy), Dedacciai (Italy), Tange (Japan), with many more depending on our location.
The tubes that make up a bicycle frame can be formed from a sheet that is shaped like a tube and welded together, or from a perforated cylinder in the case of seamless (welded) tubes.
Many of these tubes have variable changes in thickness which is called butted due to the way the thickness varies, they can be internal or external, and there are single, double and triple butted.
The thicknesses in the highest-end tubes range from 0.6mm in the thickest parts, which are those that coincide with the areas exposed to fatigue, to 0.4mm in the least exposed areas.
If you have a vernier caliper, I invite you to check what those thicknesses correspond to, since it is surprising to see the technology achieved in this steel.
Head tubes and bottom brackets tend to have continuous thickness, because they are the parts most exposed to fatigue. But even in these parts they do not exceed 2 or 3mm in thickness.
Thanks to this technology we can obtain very strong and at the same time very light tubes. The tapered areas of the tubes coincide with the areas most exposed to fatigue on the bicycle.
Columbus also patented a system of helicoidal reinforcements apart from the tapering, within a range of tubes called SLX, which is mounted on top-of-the-range bicycles.
Thanks to these qualities and the continuous technological evolution of steel suppliers, we are able to manufacture bicycles with unique characteristics.