Originally Posted by Richard Cranium
Wow, sounds like an "old-timer" discussion. Hey, I wonder if any custom-frame builders ever "mixed" different tubesets for certain sizes and types of bicycles?
I wonder what the numbers "8 5 3" mean on newer tubing?
At one time, I thought "tube numbering" had something to do with ANSI steel/alloy identification standards.
It can if it's a 4 digit # like 4130 cromo. ... 7005 and 6061 are specific aluminu alloy types...Ti is identified as CP, 3/2.5 or 6/4. Now manufacturers of steel tubing just make up numbers as they go along. 631 and 853 are the same air hardenting alloy,but 853 is heattreated for more strength. 753 was the heattreated version of 531. Columbus doesn't even use numbers.