I've got a friend here in Wisco, (a Group 6 Boss 302 racer) that owns a
restoration shop, and a business that manufactures large light poles... like
for highways and parking lots. They have a huge oven that bakes the light
poles where the base is welded to the shaft. The baking process is like 8-12
hours, and increases the strength at the weld by a factor of x 2.
-----Original Message-----
From: owner-spridgets@autox.team.net [mailto:owner-spridgets@autox.team.net]
On Behalf Of Charles Christ
Sent: Tuesday, March 07, 2006 8:47 PM
To: Glen Byrns; spridgets@autox.team.net
Subject: RE: metallurgy question
glen,
the process of heating to cherry red hot and allowing to cool is referred
to as "normalising". it's required to relieve the odd difrences between
the weld and surrounding metals. if it is not normalised after welding it
will tend to crack around the welds! it's a required procedure after any
electric welding on rollbars so they will not colapse , failing at the
welds! gas welding usually cherrys the surounding metal enough to do the
stress relief . but any form of electric welding causes (usually)
beautifuly done welds but yeilds serious brittle areas adjacent to the weld
wich if either exposed to some kind of stress or heat cycling will lead to
fractures adjacent to the weld.
chuck
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