07-09-2012, 07:04 AM
60° ends on the rod would not make allowance for the effect of the helix angle of the thread, which is considerable on a 6 TPI pitch. The 60° flanks of the thread are measured with respect to the axis of the part. The rod would be "canted" when "screwed in" and would not have full flank contact on the threads.
A better approach would be to fashion a rod with spherical ends that made contact on or near the pitch line of the thread. The helix angle would need to be calculated into the length, and hence spacing of the "ball" ends, but that is basically how the Gagemaker system works.
A better approach would be to fashion a rod with spherical ends that made contact on or near the pitch line of the thread. The helix angle would need to be calculated into the length, and hence spacing of the "ball" ends, but that is basically how the Gagemaker system works.