Steel frame heirarchy

[Illaveago]

Even with std chromoly steel, tubes come in different grades of quality. Thick walled ones for cheaper bikes, as thin as possible for lighter or more expensive ones,with even wall thickness around the tube or a bit wibbalso noticed Tube profiles vary from plain to butted (thinned out away from joints).
LHT is a robust touring bike, built for a hard life, so avoids the more racy, thin-walled, high-end steel, which is unsuitable for heavy load-carrying.

Excuse me for butting in but as you mentioned butting I would like to know if it is on the inside or the outside? The reason why I was asking was that I was measuring the tube diameter on my 60s BSA and noticed that the centre of the tube was thinner than the ends. I aslo noticed this on my brothers Holdsworth
Monsoon which is double butted.

 

[Fab Foodie]

@Steam Pig is the Kona Sutra within budget .... it's a damn looker ....

http://www.konaworld.com/sutra.cfm

 

[Steam Pig]

@Steam Pig is the Kona Sutra within budget .... it's a damn looker ....

http://www.konaworld.com/sutra.cfm

I agree, nice looking, and I did consider it, but it is a little expensive

 

[MichaelW2]

Excuse me for butting in but as you mentioned butting I would like to know if it is on the inside or the outside? The reason why I was asking was that I was measuring the tube diameter on my 60s BSA and noticed that the centre of the tube was thinner than the ends. I aslo noticed this on my brothers Holdsworth
Monsoon which is double butted.

the butting process involves hammering the ends shorter and thicker, over a mandrel to thicken the ends so they are able to cope with the heat of brazing. Welding butts are shorter and thicker. Almost all butting is interior, but occasionally you get exterior, machined ones, such as Pace aluminium frames.

 

[Illaveago]

Thank you for answering my question, I was just curious as I hadn't noticed it before. The picture in my Avatar is the the BSA. I resprayed it moss green candy to try to replicate the original colour.