# Nylon lock nuts



## yinzer (Jun 15, 2013)

I am sure that I probably should know about this, given the fact that I am as old as I am but I don't. I am making a router lift that employs a 3/4 - 10 tpi allthread. I thought I would avoid using jamming 2 nuts to lock in the bolt and get a couple of nyloc nuts. I have run across some of these in my life although much smaller than 3/4 ". And they were a slight bother but not too much. Now, trying to thread this nut onto the 3/4 in bolt is brutal.
Before I just give up and use either loctite or jam nuts I thought I would see if I am missing some step to make the initial use of this type hardware feasible.


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## johnstoneb (Jun 14, 2012)

the bigger the nyloc nut the harder they are to get on. I always used an air impact wrench. You night not want to do that on something as light weight as a router lift.


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## Lazyman (Aug 8, 2014)

Are you sure that they are the same thread pattern as the allthread? Examine the thread after you tighten it down and make sure it didn't basically cut new threads. If not, I think that they may actually make the thread a little tight on purpose so that they don't wear out too quickly and stay tight. They should loosen up with use which might be a reason not to use them.


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## Bill_Steele (Aug 29, 2013)

I agree with Bruce and Nathan. It think you should verify that the nut has the correct thread pitch for the allthread you selected. I believe 3/4" hardware comes in course (10 tpi) and fine (16 tpi) configurations. Could you possibly have 1/2-10 ACME or 3/4-6 ACME?

Nyloc nuts are a little bit harder to tighten. I recently finished a project where I used 1/2" nyloc nuts. I was able to tighten the nuts with a combination wrench and I'm not very strong. If you are really bearing down and it's not moving-I think something else is wrong.


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## yinzer (Jun 15, 2013)

It is the correct thread. The nut does go on but I don't even want to think about threading it up about an inch or two. I thought there might be some step to make it easier to thread it on the first time.


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## MrRon (Jul 9, 2009)

If it wasn't hard to install, it wouldn't serve the purpose of a lock nut. Once installed, it shouldn't be removed unnecessarily. After a few cycles of removal/re-installation, the nut will lose some of it's locking properties. On military projects, lock nuts are permitted to be re-used only once on non-critical applications, while re-use is prohibited on critical use. When absolute security is needed, nylon lock nuts cannot be used. In such a situation, fasteners have to be wired together. A critical situation would be when loss of a fastener would mean immediate failure, like an engine on an airplane. I know this is more information than you ask, but I like to pass on as much information as I can.


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## dschlic1 (Jan 3, 2013)

Are you making the Woodsmith router lift? I did the same. I ended up using a normal nut, drilled a #7 hole in one side and tapped it for a 1/4-20 screw. Easier and I KNOW that that nut will not be turning!


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## HokieKen (Apr 14, 2015)

MrRon hit the nail on the head. If you have a tap the same size, you can run it through to reduce the force of the locking plug but, that kind of defeats the purpose. I think I'd use a couple jam nuts or drill and tap for a set screw like dschlic1 did.


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