07-08-2012, 06:58 PM
I got thinking about this a bit more (even though I'm still on vacation 
) and the length of the rod would need to be less than the major diameter of the thread so it doesn't bottom out, say 3.95". You want the angled surface of the point to be the gauging surface, not the end of the rod. The pitch of a 4"-6 thread is .144", so any rod with a diameter greater than that would do for the gauge.
Tom
) and the length of the rod would need to be less than the major diameter of the thread so it doesn't bottom out, say 3.95". You want the angled surface of the point to be the gauging surface, not the end of the rod. The pitch of a 4"-6 thread is .144", so any rod with a diameter greater than that would do for the gauge. Tom
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