Yes, i
think ive seen all of them at this point (ASE Master Auto Tech), and i like those a bit more than most others because they dont leave as much damage behind.
Just some background from what i know: what we call locknuts or locking nuts are technically called prevailing torque nuts.
They work various ways but in the case of nuts specifically there are a few common types. Some nuts are ‘made correctly’ and then intentionally distorted near the top so that the threads are no longer ‘round’ and you have to ‘stretch it back to round’ to spin it on. Those usually have machine pressing/punching marks on them near the top. Wouldn’t use that on stainless as they rub the threads together hard enough to leave damage on the male side. Id say high risk of galling on stainless.
The one there in your pic is pretty rare, i think because it’s harder to manufacture. That one basically has the last thread on top at the ‘wrong pitch’ and when you force it on it flexes those ‘thread wings’ to fit in between the threads on the male, so the friction is limited to the sides of the threads instead of the ‘ridge’ or ‘crest’ of the threads, leaves less damage. I like those ok.
Nylock or nylon ring lock nuts have an unthreaded plastic ring on top of threads that you must stretch/force over the male threads. Those leave basically no damage but also don’t grip as hard as some others and plastic will get soft and lose grip if it gets hot.
Serrated nuts are ‘flange nuts’ which basically means has a washer built into the bottom to make the base wider. The serrations on the bottom are angled to act sort of like a ratcheting mechanism, they can slide easier clockwise and try to dig in on counterclockwise rotation. I think those can be pretty great IF the fastener and the surface you’re clamping onto can have the right combination of pushing the nut into the surface hard enough to actually gouge into the metal. If you use it with a soft bolt on top of a hard surface it’s not going to be great. Split ring lock washers function similarly but only bite in one spot and in general i think they suck compared to serrated nuts.
So if you’re picking prevailing torque fasteners you have to decide if you’re ok with them leaving any damage, and if so would you rather it be on the male threads or the clamped surface. None of them are technically recommended to be reusable athough i think serrated nuts pretty much are as the sacrificial surface is supposed to be the clamped part, not the nut. In the end i have nylock nuts on my stainless terminal studs because there’s no vibration and very little heat in my application and the male threads are somewhat soft bolts i welded onto something and i dont want to wear on the bolts much, and the clamped surfaces are small 5/16” ring terminals which a split washer or serrated nut would tear up.
I love this video.
