Re: [CR]Re: Not negative just reality, and frames go soft


Example: Framebuilders:Alberto Masi

Date: Mon, 20 May 2002 10:45:28 -0700 (PDT)
From: Tom Dalton <tom_s_dalton@yahoo.com>
Subject: Re: [CR]Re: Not negative just reality, and frames go soft
To: classicrendezvous@bikelist.org
In-Reply-To: <103.158dd310.2a19caa0@aol.com>


Once again, I'm not an engineer, nor do I play one on TV, but.... Could it be that this notion of frames routinely "going soft" has been established because frames are routinely failing, but the failures go unnoticed? Could it be that the "failures" are microfracturing and that this happens to any thoroughly used lightweight steel frame? I'm just throwing out a possibility that is based almost entirely in my own conjecture, but I have to wonder if small-scale fractures that aren't throughgoing wouldn't make the effective wall thickness of a tube considerably thinner, thereby making the tube more flexible.
>Having just read a book on the first steel bridge, the Forth Bridge, and
>wondering how it's stood this long, in NoHo. Ca

Wondering if this bridge was built to be stressed in such a way that it doesn't exceed fatigue limit and can therefore be put through an infinite number of stress cycles without failure, and further wondering if this level of robustness is ever seen in bike frames...

Tom Dalton Philcycles@aol.com wrote:

In a message dated 5/19/02 7:00:14 PM, NortonMarg@aol.com writes:

<< Some frames, do go soft. How long a frame lasts depends on a lot of things. There are a lot of variables regarding craftsmanship, brazing, heat, overheat, etc., that affect this. To categorically say that "frames don't go soft, that's a myth" is just plain wrong, (mostly incomplete). It depends. Stevan Thomas Alameda, CA >>

You fail to differentiate between normal use and wear and damage. Damaged or improperly made frames don't "go soft," they fail because of damage or improper construction. "Going soft" implies some failure of the material from which the bike is made. Phil Brown Having just read a book on the first steel bridge, the Forth Bridge, and wondering how it's stood this long, in NoHo. Ca