[TowerTalk] 2 inch Chrome Moly mast needed

[Jim Thomson]

Date: Fri, 8 Apr 2016 07:47:44 -0700
From: "Jim Thomson" <jim.thom at telus.net>
To: <towertalk at contesting.com>
Subject: [TowerTalk] 2 inch Chrome Moly mast needed


##  watch out with the 1026 DOM that?s available at some steel suppliers,
esp the franchised   metal  super marts etc.   The yield strength varies 
a  bit.   I have seen as low as 75 ksi..and as high as 87 ksi .  Others have seen
an even wider variation in extremes.   Some of the galvanizing jobs that hams  have had
done turn out pretty good, and some are not so good.     Array solutions stuffs a TV camera
down the inside to check the inside galvanizing job.  Same setup as what plumbers use.

Jim  VE7RF  


@@@@  ditto with  4130 chromolly steel.  UN heat treated, its  only 70 ksi. 
When you see dirt cheap  4130 CM steel at a steel yard, that’s  why. 

@@@  The heat treating process is typ done at 1350 F.   The galvanizing process
is typ done at 875-900 F.    The galvanizing process will not screw up the prior heat treating
process. 

Jim   VE7RF