Conification
Butting (or butted; see cone ) is the formation of a component whose wall thickness is thicker at the ends or in the middle of the component than at its center or at its ends. In bicycle technology, spokes, handlebars (especially for mountain bikes ) and frame tubes are referred to as conification.
Other names
Konifzierung is also known under the designation "thickend" or "double thickend" . In the English-speaking world, spokes are also referred to as swaged , in German "squeezed" .
technology
Butted frame tubes are shaped with the same outer diameter so that the wall thickness is higher at the tube ends. This is intended to make the pipes more durable at the ends at which the forces are introduced and where increased internal stresses occur due to soldering or welding . In the middle, the stress can be higher and thus weight can be saved.
When speaking of double-butted or "double butted" it means that the wall thickness of frame tubes is thicker at both ends than in the middle of the tube. The term thickend refers to the fact that the butted spokes or frame tubes have thick ends. However, the production is exactly the opposite: with spokes, the thinner center is created by squeezing the material.
Frame construction
In frame construction, butted tubes were common with high-quality steel frames. Both Columbus and Reynolds offer butted tubing. Alan was one of the first wheel manufacturers to transfer the technology to aluminum tubes .