Vibration

[Seadog]

An interesting comparison on the effectiveness of washers and locknuts.

profchapuy on Instagram: "Tests de vibrations avec plusieurs moyens de serrage #bacpro #mspc #maintenance #engineer"

83K likes, 453 comments - profchapuy on September 18, 2023: "Tests de vibrations avec plusieurs moyens de serrage #bacpro #mspc #maintenance #engineer"

www.instagram.com

 

[bricol]

Can't see it - but there's a 60's NASA document that poo-poos spring washers people seem so keen on using . . .

I'm always amused by people (including my colleagues) using expensive Nordlock washers . . . over plain washers . . . somewhat, well, entirely, defeating their entire reason to be used.

 

[Seadog]

It ends up with the Nord-lock. The only arrangement that doesn't vibrate loose.

 

[MattF]

It ends up with the Nord-lock. The only arrangement that doesn't vibrate loose.

Does it mention/test copper washers?

 

[Seadog]

No. Plain, spring, the pressed-spring steel locknuts, plain locknuts, nyloc nuts, and then, I think, Nord-lock washers.

 

[MattF]

I use copper washers when I want locking. Detest the spring & star washers. Never tried the Nord-locks.

 

[Erie Fred]

I'm surprised at this lot around here.....no-one thought to post this ?

 

[500e]

They broke up I thought

 

[Erie Fred]

They broke up I thought

But the Moosic lives on.
Brian can't hit those high notes anymore, but we have it all on Ampex tape.

 

[premmington]

Nord lock washers are reuseable - where a Nyloc nut is not.

Loads of advantages to Nord locks - temperature resistant - plus once released they don't hold to the thread when undoing them (if you know what I am trying to say?)

But in the automotive world - Nord locks are never used - never seen! Don't know why?

---------

I hate spring washers...

 

[doubleboost]

Split pins simply work

 

[Seadog]

They broke up I thought

Not rwally, two of them died.

 

[mart]

I suppose the method of choice is down to the application. For example, I fitted a light bracket to my cycle rack. M6 x 40mm set screw , but with 2 nuts tightened in opposite directions. I feel confident that they will be ok for such a basic application. Pot holes etc.

I am curious enough about this subject to ask about setscrews & bolts that are used without anything other than the actual thread to keep them tight.

Gearbox to engine, car wheel nuts etc. I will assume the bolts of HGVs and buses can work lose? I've seen them plastic pointers that are fitted to each wheel to flag movement.

 

[Erie Fred]

I didn't see bolt stretch being tested.

 

[Morrisman]

Can't see it - but there's a 60's NASA document that poo-poos spring washers people seem so keen on using . . .

I'm always amused by people (including my colleagues) using expensive Nordlock washers . . . over plain washers . . . somewhat, well, entirely, defeating their entire reason to be used.

Yes, I bought a hot rod off a guy who had used both flat washers and spring washers on almost every bolted location.

I use Nylok nuts anywhere I can. Obviously not perfect, judging by the video, but they won't spin off once they do become loose, like normal nuts would. But I've never actually had one come loose, ever. And I've built a few cars and bikes from the ground up.

 

[Seadog]

Yes, I bought a hot rod off a guy who had used both flat washers and spring washers on almost every bolted location.

Actually that was another of the combinations. It acts just like a plain washer, i.e. there is little to no vibration resistance.

 

[Morrisman]

Actually that was another of the combinations. It acts just like a plain washer, i.e. there is little to no vibration resistance.

Exactly. You basically don't need a flat washer unless the surface you are putting the nut onto is either rough, or not level. No need to use one on a hard flat surface. I do it anyway, as it looks neater and more finished.

 

[PhillipM]

But in the automotive world - Nord locks are never used - never seen! Don't know why?

Expensive, add assembly cost with them being paired.
In motorsport they're used a lot. it's the only thing that will keep my CV bolts from shocking loose, up to and including a full inch of threadlock on the threads...

 

[bricol]

I use Nordlocks when needed - quite often people do over-specify them.
Spring washers are simply weak flat washers when tightened.

I had to rapidly find a solution to SKF lock nuts backing off holding bellville washers providing bearing pre-load in a $3m machine earlier in the year - Whittet Higgins are rather good! Not bad pricing in the US - a bit dearer if you buy them here.

CNM Clampnut

The CLAMPNUT with ISO metric threads.

www.whittet-higgins.com

 

[sako243]

But in the automotive world - Nord locks are never used - never seen! Don't know why?

As @PhillipM says its down to cost but also simplicity. It's not uncommon these days to have "special" bolts where a large bolt has a smaller head on it. For some reason they may need a thicker shanked bolt but not done up to a silly torque (or for example if it's going into aluminium). That way the monkey assembling the car doesn't need to know that this 16mm bolt needs torque a and this 16mm bolt needs torque b. 16mm socket means torque a and 14mm socket means torque b.

I think it was on the JLR production line where I saw that torque wrenches had the sockets permanently fixed to them and were fixed at a specific torque. Different head size equalled different torque. Having to add a nord lock into the mix just complicates matters.