Originally Posted by
baxtefer
Note how he says that the tubes are "custom drawn to their specification". There are a number of excellent tubing companies in Taiwan that do exactly this. Draw tubes to whatever diameter and butting profile you want. Even in small batches. Kogswell makes extensive use of "Eco" brand tubing (which you would call "generic" 4130) which they have butted, in small batches to whatever spec they want. Kogswell runs really small batches from the Maxway factory, and Eco draws them tubing with frame-size-specific butt profiles in tiny, tiny batch sizes.
We used to use Maxway. We've moved on to other frame shops now.
But what you've said is still perfectly accurate. Surly steel frames are made at Maxway and Maxway and QBP can work with the Taiwanese tubing vendors to optimize the tubes that get used in their frames. I've talked to QBP designers and while they were reluctant to give me details, they do indeed put a lot of thought into tubing specs.
Reports of the decline of steel tubing production are exaggerated. Columbus does
not routinely make steel tubes with the butt profiles needed for lugged construction. But for the Taiwanese vendors it
is a routine matter.
One thing to remember about 4130 is that was widely accepted
because it was an alloy that was well suited to the kinds of things that steel is asked to do: it's strong, it lends itself well to heat treating and it can be welded. The other thing to remember about 4130 is that the aerospace and hydraulic industries made vast improvements to its production processes in the later part of the twentieth century.
Modern 4130 is a material with a tremendous value ratio.