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RE: Threaded Stainless Steel Rod

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>The reason I avoid the AISI grades is that the mechanical properties vary
>with the manufacturer.
Absolutely bang on. _Always_ use ASTM specs for load-bearing material. 
I'd like to emphasize this with a story of my own involving a particular 
supplier's brand name of quenched and tempered steel plate. We used the 
brand name to order material which was duly supplied us. After we'd used 
much of it we found our steel had the [proper brand name but had been 
specially heat treated to a very high hardness and was nowhere near as 
tough as we needed. We had no recourse, and we ate the order. We got 
exactly what we said; the supplier wasn't at fault because he didn't know 
what we meant. Had we referenced the proper ASTM spec, we would have had 
received the steel we had in mind and clear grounds for rejecting the 
material. We would also not have had to wait around for one particular 
manufacturer to roll what we wanted and stamp his brand on it. This was a 
very difficult and expensive material QA lesson. ASTM specs provide not 
only chemistry but minimum strength properties, appropriate toughness 
requirements, fabrication and processing practice and dimensional 
tolerances. If you don't cover yourself this way, you're effectively 
letting a supplier make your material choices for you, and sure as eggs 
is eggs you'll wind up holding the brown end of the stick. 

Christopher Wright P.E.    |"They couldn't hit an elephant from
chrisw(--nospam--at)        | this distance"   (last words of Gen.
___________________________| John Sedgwick, Spotsylvania 1864)