propsync
Well Known Member
Hi group,
On to torque'ing the ribs to the spar, 12-07 step 2.
I'll be torque'ing AN3 bolts to MS21042-3 nuts. Using the chart on 5-12 (vans mistakenly says 5-19 and then later 5-20), standard nuts get a torque of 20-25 in/lb and the self locking gets 28 in/lb.
But their explanation of what to add for friction drag doesn't make sense. I'll quote right out of the book.
"AN3 bolts and MS20142-3 all metal lock nuts testing showed the friction drag torque at 14 in-lbs. This results in a final torque setting on our wrench of 14 plus 20 or 34 in-lbs."
They are using the number from standard nuts, not self locking.
Shouldn't the number be 14 + 28 = 42 in lbs.??
On to torque'ing the ribs to the spar, 12-07 step 2.
I'll be torque'ing AN3 bolts to MS21042-3 nuts. Using the chart on 5-12 (vans mistakenly says 5-19 and then later 5-20), standard nuts get a torque of 20-25 in/lb and the self locking gets 28 in/lb.
But their explanation of what to add for friction drag doesn't make sense. I'll quote right out of the book.
"AN3 bolts and MS20142-3 all metal lock nuts testing showed the friction drag torque at 14 in-lbs. This results in a final torque setting on our wrench of 14 plus 20 or 34 in-lbs."
They are using the number from standard nuts, not self locking.
Shouldn't the number be 14 + 28 = 42 in lbs.??