Ramp-Lock Lock WashersThe principle is simpleTightening the fastener the washer halves go "click-click-click" as they revolve against one another.Trying to back off the fastener, special hardened teeth on the underside of the washer bites into the parent metal. The complete washer does not spin.The washer has to separate the washer halves.Only there is a ramp on both sides of the washer faces.And the ramp is of a much steeper angle than the nut or bolt thread angle. Where one turn of a washerless fastener may allow a fastener to rise 1/16" inch, the ramp lock washer has be forced 1/8".In short, they do not back off accidentally, everAnd they need no heat like Loc Tite RED does to loosenWhen I build an extremely high amp switch board this is what I use.Or high amperage alternators. The through-case bolts.

Looks like lug nuts on Ford vehicles. They have the same ribbed construction on the nut to rim surface.

There would be two parts, facing each other and THAT size you would need a five foot long 1" breaker bar. The # 10 size I use for alternator cases bends an Allan Wrench into an arc before it overcomes the ramp climb.SPIN LOC nuts have ribs but are not the same thing at all.

Oh I don't know. Had to change a tire on an F-350 Custom 10,000 GVW straight truch, this has tires and lugs nearly as big as my RV (22.5, i Suspect it's 19's on the F-350)Using the standard Ford Truck lug wrench off the inner fender. I broke one lug and got the other 9 off no sweat. Put 'em back on and later when the corporate Tire Guy put his big Impact wrench on.. It was touch and go for they did not wish to come off.. I got 'em that tightOf course I was younger then.

The idea is very similar to what Audi/VW uses to bolt ring gears to differential carriers. I've NEVER seen them come loose if torqued properly. Audi/VW usually use fine (ISO 1.0mm) treads so a given torque gives more clamping force than the treads shown in your photos. They bite/lock really well especially on hardened materials.Chum lee

If you have the two piece Ford lugnuts, they are to be lubricated with a drop of oil between the two parts. I doubt that ever happens on most.

When You REALLY Don't Want A Bolt Or Nut Backing Off...

agesilaus
Explorer III
Mar 31, 2018
Looks like lug nuts on Ford vehicles. They have the same ribbed construction on the nut to rim surface.
MEXICOWANDERER
Explorer
Mar 31, 2018
There would be two parts, facing each other and THAT size you would need a five foot long 1" breaker bar. The # 10 size I use for alternator cases bends an Allan Wrench into an arc before it overcomes the ramp climb.

SPIN LOC nuts have ribs but are not the same thing at all.
wa8yxm
Explorer III
Mar 31, 2018
Oh I don't know. Had to change a tire on an F-350 Custom 10,000 GVW straight truch, this has tires and lugs nearly as big as my RV (22.5, i Suspect it's 19's on the F-350)

Using the standard Ford Truck lug wrench off the inner fender. I broke one lug and got the other 9 off no sweat. Put 'em back on and later when the corporate Tire Guy put his big Impact wrench on.. It was touch and go for they did not wish to come off.. I got 'em that tight

Of course I was younger then.
Chum_lee
Explorer
Mar 31, 2018
The idea is very similar to what Audi/VW uses to bolt ring gears to differential carriers. I've NEVER seen them come loose if torqued properly. Audi/VW usually use fine (ISO 1.0mm) treads so a given torque gives more clamping force than the treads shown in your photos. They bite/lock really well especially on hardened materials.

Chum lee
Lynnmor
Explorer
Apr 01, 2018
If you have the two piece Ford lugnuts, they are to be lubricated with a drop of oil between the two parts. I doubt that ever happens on most.
agesilaus
Explorer III
Apr 01, 2018
Lynnmor wrote:
If you have the two piece Ford lugnuts, they are to be lubricated with a drop of oil between the two parts. I doubt that ever happens on most.

That's the first time I've heard that. Maybe some day I'll RTFM
marcsbigfoot20b
Explorer
Apr 01, 2018
MEXICOWANDERER wrote:

Ramp-Lock Lock Washers

The principle is simple
Tightening the fastener the washer halves go "click-click-click" as they revolve against one another.

Trying to back off the fastener, special hardened teeth on the underside of the washer bites into the parent metal. The complete washer does not spin.

The washer has to separate the washer halves.

Only there is a ramp on both sides of the washer faces.

And the ramp is of a much steeper angle than the nut or bolt thread angle. Where one turn of a washerless fastener may allow a fastener to rise 1/16" inch, the ramp lock washer has be forced 1/8".

In short, they do not back off accidentally, ever

And they need no heat like Loc Tite RED does to loosen

When I build an extremely high amp switch board this is what I use.

Or high amperage alternators. The through-case bolts.

We have a few bins of those at work in stainless. 3/8 size currently holding my 99 Tahoe header collectors together. They work pretty good.
Double nutting the end of a bolt is near unbeatable.
mike-s
Explorer
Apr 01, 2018
You'll be amazed to learn about Loctite!
Lynnmor
Explorer
Apr 01, 2018
agesilaus wrote:
Lynnmor wrote:
If you have the two piece Ford lugnuts, they are to be lubricated with a drop of oil between the two parts. I doubt that ever happens on most.

That's the first time I've heard that. Maybe some day I'll RTFM

Here is a copy and paste from my manual:

On all two-piece flat wheel nuts,
apply one drop of motor oil between
the flat washer and the nut.
agesilaus
Explorer III
Apr 01, 2018
Lynnmor wrote:
agesilaus wrote:
Lynnmor wrote:
If you have the two piece Ford lugnuts, they are to be lubricated with a drop of oil between the two parts. I doubt that ever happens on most.

That's the first time I've heard that. Maybe some day I'll RTFM

Here is a copy and paste from my manual:

On all two-piece flat wheel nuts,
apply one drop of motor oil between
the flat washer and the nut.

I wasn't doubting you I had just never heard of that before. It's good to learn one or more things every day...heh.