It seems like someone mentioned "dimpled nuts" so here's some info I have on locknuts. There are none I can remember on my Craftsman Intek 24, but maybe someone will find this useful.
Engineers call it "prevailing torque" but turning torque seems simpler. Different locking features of such nuts (1) nyloc -plastic ring (2) crimp or oval head (3)split beam (4)button or dimple (5)plastic patch -sometimes on the bolt.
When you thread on the nut you feel interference which resists hand threading. If you hold the bolt head and tighten with a beam style torque wrench you can see the turning torque in inch or ft lbs. This value is added to the fastener clamping torque UNLESS the application comes with such a combo, and a torque is given by manufacturer. The best combo example of this may be the automotive pinch bolt for ball joints which includes a locking nut and rolls total torque into one figure.
Except for the nyloc and plastic patch these nuts can degrade the bolt threads. It is up to you to judge. Often one use is specified. Picture below is a random "mix and match" from my grab bag. None was a combo; all are used. FYI
Engineers call it "prevailing torque" but turning torque seems simpler. Different locking features of such nuts (1) nyloc -plastic ring (2) crimp or oval head (3)split beam (4)button or dimple (5)plastic patch -sometimes on the bolt.
When you thread on the nut you feel interference which resists hand threading. If you hold the bolt head and tighten with a beam style torque wrench you can see the turning torque in inch or ft lbs. This value is added to the fastener clamping torque UNLESS the application comes with such a combo, and a torque is given by manufacturer. The best combo example of this may be the automotive pinch bolt for ball joints which includes a locking nut and rolls total torque into one figure.
Except for the nyloc and plastic patch these nuts can degrade the bolt threads. It is up to you to judge. Often one use is specified. Picture below is a random "mix and match" from my grab bag. None was a combo; all are used. FYI
