View Full Version : Best way to lock a nut to a bolt?


PoiToi
10-24-2007, 06:09 PM
Hello all, i have a simple question (at least for some of you i'm sure =) ).

What is the best way to lock a nut on a bolt? I know 2 nuts tightened together works well, but I was wondering if there was any better way to do it..I 've noticed that sometimes with that method you can still turn the nuts together by just turning one.
The bolt will be subjected to high heat (500+ F) so a nylon nut is definately not the answer. I know they sell high heat loc-tite but I want to be able to take it apart when i need to.

Mcgyver
10-24-2007, 06:49 PM
check loctite's site, iirc even the high temp loctite still comes apart with heat, its just effective at a higher temp. I know i've use their 620 high temp retaining compound and it comes apart with heat (obviously more than the temps its intended to be good for) but double check the high temp thread locker

Geof
10-24-2007, 07:14 PM
Use a castellated nut and put a split pin through a hole in the bolt.

If the bolt and nut is big enough put a diametral saw cut 3/4 of the way through the nut then drill and tap for a small bolt to pinch this cut and lock the nut against the threads.

MrWild
10-24-2007, 07:42 PM
The absolute cheapest yet sure fire locking nut is to take a standard nut and give it a squeaze in the vice. You will have to experiment a little how much squeaze to do, but these work VERY well. This is the some principal as the lock nuts with the center punched dimple on one facet. Both deform the nut causing it to squeaze on the threads.

mxtras
10-24-2007, 09:10 PM
You could use an all metal locknut, but they are not my favorite.

The best method might be to use safety wire.

Scott

PoiToi
10-25-2007, 07:11 PM
Mr Wild, do you mean squeeze the not after it's threaded on? or before and then put it on with some force?
either way might work.

geof, i really like that idea!
i dunno if the nut is big enough, if nothing else i think i can manage to make something here at work!

dertsap
10-26-2007, 03:10 AM
you can buy solid steel lock nuts , cheap and effective ,
http://www.fastenal.com/web/products/detail.ex?sku=37278

mxtras
10-26-2007, 08:21 AM
No love for the safety wire idea, huh?

JROM
10-26-2007, 11:47 AM
In the airplane and race car biz. if you don't want it to come loose you use safety wire.
It's an elegant fix and it looks sexy.

Andre' B
10-26-2007, 12:32 PM
One of these works great for the locking part.
http://en.wikipedia.org/wiki/Ball-peen_hammer

Add one of these for the removal part. :)
http://en.wikipedia.org/wiki/Chisel#Cold_chisel

Geof
10-26-2007, 12:54 PM
One of these works great for the locking part.
http://en.wikipedia.org/wiki/Ball-peen_hammer

Add one of these for the removal part. :)
http://en.wikipedia.org/wiki/Chisel#Cold_chisel

I did think of suggesting the Arc Welder/Sawzall combination for fixing and removing; I am partial to power tools not hand tools.

RickWG
10-28-2007, 08:15 PM
Zap it with the MIG :)