[AT] Heat treating tractor parts

[DieselBob at aol.com]

I agree with Bruce on this, harden and temper to about HRc 36 for a good  
compromise between strength and toughness.  The other thing you can do is  to 
reduce the diameter of the bar to almost the root diameter of the thread if  the 
design allows for it. (if it is not running through a bushing or  something).  
In fact, ideally the whole rod could be reduced to that  diameter.  What this 
does is make the rod a bit more flexible to absorb  impact and actually 
reduces the stress at the threads when there are large  impacts.  The other thing 
to do is to have there threads  rolled instead of cut. This work hardens the 
root of the thread and  strengthens it.  All high quality grade 8 bolts are made 
that  way.
 
Bob