I'd like to search for this style of nut but don't know what to call it!

Though not really visible in the pic the round section has some lines that look like serrations.

Can anyone help with the correct nomenclature?

Thanks

 

Looks like one of those nuts on the brake levers of a bicycle... Those to adjust the tension in the cable...

 

Is the insert Nylon? AKA a nylock?

 

There's no insert, and it isn't a locking nut. Or, if there ever was a locking capability, it is worn out.

Looks like it might be very British-esque and arcane. It's off of a 1967 AC Cobra.

A "Dunk Nut"comes close....but not quite 100%

Mainland Fasteners | Dunk Nuts (Hank Bush)

Cheers
DD

 

Just guessing, it might be some type of prevailing torque lock nut. That would be consistent with the theory of the bicycle cable adjustment function. I was thinking the little marks around the narrow perimeter might be where a machine pinches it to create the interference fit. Does the knurled portion look like its not perfectly round or like the threads in that portion have any deformation?

 

Dang Doug! That’s my country well the other island I would have called those rivnuts maybe its a trade name. But thanks for the link it might come in useful for my purchases

 

I'll have to look more closely....but it's on my workbench at the shop right now.

The 'serration' type marks are not entirely uniform...which suggests it may have been pinched by some sort of tool

Cheers
DD

 

Found it !

"Cleveloc Nuts"

https://www.triumph-spares.co.uk/516...-thick-14-1202


Cheers and thanks

DD

 

Being a mechanical tech nerd, found this: Simmonds Marshall | Cleveloc & All Metal Self Locking Nuts

CLEVELOC DESIGN
The Cleveloc nut is a low cost one-piece self-locking nut with superior locking and re-usability characteristics. The locking collar is an integral part of the nut and is formed into a geometrically developed ellipse. This provides two locking elements of consistently uniform shape and thread contour which permit the bolt threads to engage smoothly during assembly.

There are no thread interruptions or pitch errors to react unfavourably or to induce galling on the bolt threads. The two locking elements utilize most of the collar portion of the nut and the threads that come within its depth. The elliptical form of the locking collar with its distribution over wide areas of the locking pressure, ensures a high fatigue life with necessary flexibility to give consistent performance and dependability in service. These locking elements are designed to create gradually increasing areas of pressure and friction on the bolt threads.

Further tightening forces the locking elements to engage more fully with the bolt threads and this increasing resistance to the entry of the bolt brings the full length of the nut threads into close contact with the working faces of the bolt threads. Further friction is created and both forces combine to give a smooth, progressive and increasing self-locking action.