In a message dated 7/1/02 8:14:26 PM Eastern Daylight Time, NortonMarg@aol.com writes:
> In a message dated 7/1/02 3:38:41 PM Pacific Daylight Time, GPVB1@cs.com
> writes:
>
> << What exactly are "soft joints?" What do you think yields when you cold
> set a
> lugged steel frame? It's not the joints, it's the tubing (it's bending, or
> worse, buckling in some cases). >>
To which Stevan replied:
> It is the tubing in the heat affected zone (joint) that moves. It's all
> glued together and equally weak, so it's hard to say exactly what is
> moving. All I can tell you is that some frames offer little or no
> resistance to cold setting. Something is soft and logic dictates it's the
> part that was hot that has lost considerable strength. The same tubing,
> silver brazed makes a different beast. Alignment tables are quite
> educational.
>
Stevan:
> A) Please explain EXACTLY what two things you are comparing. I think you
> have too many variables there. If the EXACT same tubing with the EXACT same
> dimensions/ gauges/etc. is being compared after being brazed by the same
> person into IDENTICAL frames, but with the only variable being brass vs.
> silver, I'll be more receptive to your argument. More heat can mean more
> annealing (softening) of the steel. Steel is an incredibly tough, durable
> material though....
>
> B) The HAZ is outside the joint.
>
> C) A properly-made bike frame never yields during use, so it doesn't really
> come in to play on the road if there is a slight difference anyways. It
> doesn't matter whether your frame's yield point is five times normal use
> stress or ten times, The Safety Factor is large in either case.
>
> Cheers,
>
> Greg "steel frames don't go soft" Parker
> A2 MI USA