Originally Posted by
fietsbob
the heat treatment of the finished part helps make for a less bendable length,
a mix of ductility and hardness, made by Heating and Quenching when that heat is reached ..
OP got a cheap Folding biker ,maybe he will send a picture..
Copper is a Non ferrous metal , piping is sold annealed for plumbing, to be flexible for fitting.
so a weak example .. metallurgical apples v oranges
when comparing with a tempered steel alloy., or high strength say 7075-T6 Aluminum.
You missed my point.
I was arguing for the ease of bending different diameters of tubing.
Larger diameter tubing is more difficult to bend and twist compared to smaller diameter tubing.
It's quite evident with the use of oversized tubing on aluminum frames or larger axle sizes (15mm and 20mm vs. 9mm and 10mm) for downhill bikes.
Now, just because you give the tubing a thicker wall, it doesn't make it stronger compared to making diameters larger. The main thing thicker walls help with are resistance to denting and punctures.