Lock nuts vs lock washers

[TerryMason]

I've never really used lock nuts (the metal nuts with nylon inserts in them), but recently I ran out of lock washers while installing my new engine skid, and used one of the lock nuts I had laying around.

I was curious - when should I use lock nuts and when should I use lock washers? Is one better than the other?

 

[JPNinPA]

Like the statistician says 'It depends'. Teflon lock nuts are best for low torque, low temp and softer metals. Lock washers are better in high torque, high temp and harder bolt materials.
There may be more reasons but thems da basics.

 

[Ghost Rider]

Like the statistician says 'It depends'. Teflon lock nuts are best for low torque, low temp and softer metals. Lock washers are better in high torque, high temp and harder bolt materials.
There may be more reasons but thems da basics.

I second that! Also lock nuts are more expensive than lock washers. Also lock washers are more common and easy to find in any store. I wouldn't recommend lock nuts in high temp applications.... The cool thing about lock nuts is that sometimes you might want to leave the nut loose a bit for two parts to be able to move freely against each other. You can tighten the nut then back it up a little bit. If you use lock washers then you will need double nuts to lock them agains each other. I personally like the lock nuts because it gives a project a cleaner look....