Hi Tony
I think a good solution would be a high tensile steel, deeper hardening may
reduce the strength of the shaft making it more likely to break under a
shock loading, this does happen as I dropped a pin I had hardened before I
tempered it and it snapped when an untreated item would bounce, fortunately
I was able to replace it easily!
Graham.
----- Original Message -----
From: Tony Rhodes <ARhodes@compuserve.com>
To: <technical@iwnet.screaming.net>; Triumph List <triumphs@autox.team.net>
Sent: Thursday, March 16, 2000 11:56 PM
Subject: triumphs@autox.team.net digest #2027 Thu Mar 16 02:35:00 MST 2000
Message text written by INTERNET:triumphs-owner@autox.team.net
>From: "Graham Stretch" <technical@iwnet.screaming.net>
Subject: Re: Machine shop work
Hi Douglas
>but 60-62 on the Rockwell C scale should damn
>near put flats on the teeth of your file,
Well, the file does skip across the steel.
>Hey presto instantly you loose 1/3 of the hardness thickness, though 0.020"
should be
>reasonably good for the task in hand.
I think the issue is the thickeness of the hardened surface, and the
ductility of the
steel under the surface. As the rollers go over the surface, they do not
damage the surface at
all, but they appear to fatigue the transition layer. Eventually there is a
shell
of hardened surface which finally starts to peel off.
I think we need to go with a thicker hardened surface, and maybe a harder
steel underneath. What is should be, I don't know. I am sure SOMEONE
knows.
-Tony
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