"Leanne" wrote in message ...
"Glenn Ashmore" wrote in message
news:2P5Bc.1470$Pa4.98@lakeread04...
Has anyone ever had any experience with or heard of a Nyloc nylon lined
nut backing off a bolt?

Now the problem. A New Zealand sailor is claiming that his anchor
(which thankfully I did not sell) failed because the nut backed
completely off the bolt which allowed the bolt to fall out. There is
very little vibration and no torque on the bolt. The nut was in good
condition, new when installed and had never been removed. Is there any
way that a Nyloc nut in good condition could possibly make more than 20
turns on a loose bolt on its own?


Aren't the Nyloc nuts for a one time use. I know the similar type in
aircraft are that way. One solution would be to double nut it with a
standard nut and then a nyloc on top of it. Myself, I would drill the bolt
and use a cottor pin so the nut could not run off the end of the bolt.

Leanne
s/v Fundy

Your correct, they are supposed to be used one time, the nylon looses
it's grip with repeated removals. You will note this when installing
an old used one, it starts to go on with little effort at all, a new
one requires w wrench.