On Jul 17, 5:33*am, Jim Wilkins wrote:

IIRC experiments on torqueing aircraft fasteners showed a 2:1
variation in clamping force vs torque from surface roughness etc under
the best conditions. ..
jsw

Just this week I did an experiment [for Mosin Nagant scope mounting]
that compared torque to strip out three turns [.1" thick steel] of
10-32 female threads in mild steel:

a) waxed: calculated 17.8 in lb, but got a 15 and a 16 inch pound
yield
b) lubed: calculated 26.5 in lb, but got yield at 28 in lb
c) dry: calculated 34.7 in lb, but got yield at 34 in lb

What does it all mean?
Close to 2:1