What are these nut things called?
 

I think they are fitted tightly into sheet metal by banging on the open end as a decent alternative to self-tapping holes, that just get bigger and bigger if used too often.

These are 6 BA. I can see the one with the serrated shaft would grip the sheet it's bashed in to, but no idea what purpose the serrations on the other has around its shoulder.

Anyway, what are they called?

Thank you.

Ian

Re: What are these nut things called?
 

I have always known them as Nut Serts.

Cheers

Mike T

Re: What are these nut things called?
 

Clinch nut.
Rob

Re: What are these nut things called?
 

They are known by various names, for instance Nutsert, Hank Bush, Hank nut, Rivet Nut and come in various forms.

Most have to be riveted into the sheet.

Some have serrations to better grip soft materials.

The Clinchnut is pulled into the sheet with a special tool and can be used where there is no access to the rear of the sheet.

There are also self clinching fastners which are simply pushed into the material without the need for special tooling and in extremis can just be fitted with a hammer.

Re: What are these nut things called?
 

Cromwell Tools call them rivet nuts made by, Qualfast. Cromwell only sell them in large quantities (500)

Trevor

Re: What are these nut things called?
 

PEMs

A name picked up from one of the major manufacturers. for the self-clenching type where the panel metal is forced to clench itself into a groove in the fastener. Splines stop it spinning.

David

Re: What are these nut things called?
 

-I always called them Rivnuts (that's a trademark). Used a lot of them in situations where thin aluminium covers needed to be retained but be easily and repeatably removed (so tapping direct into the aluminium would have failed rapidly)

This place: https://www.rivetwise.co.uk/rivets/rivet-nuts.asp - has a good selection.

Re: What are these nut things called?
 

I bought some a few years ago now, they were sold under the name of Hank bushes.
I specifically needed 4BA threads to replicate some 1940's parts, and found BA sizes very hard to find, whereas metric were readily available.

Andy

Re: What are these nut things called?
 

If all else fails, and extreme strength is not needed, it should be possible to run a BA tap through a slightly smaller Metric-sized nut, drilling out to enlarge the bore if necessary.

Re: What are these nut things called?
 

Only once per tap - the bushes are usually hardened.

Re: What are these nut things called?
 

Pedantic mode, BA is metric based on 6mm as 0BA and reducing a sensible amount per iteration.

Re: What are these nut things called?
 

I must admit to not having tried to re-tap this type of fastener, but I have done it on a different type of threaded insert (pressnut) to allow a M3 pressnut to be used as a hand-tightenable substitute for a knurled terminal nut on a long 6BA thread. Pressnuts have a serrated ridge on the outside rim of their flange which provide serviceable finger grips. Not to be confused (although they often are by on-line sellers) with pressed nuts, which are nuts made from sheet metal stampings rather than from drilled square or hex rod.

Re: What are these nut things called?
 

Thanks everyone for the thoughtful and helpful replies. Lots of leads there.

Ian

Re: What are these nut things called?
 

They can't be hardened if you are going to swage them onto a sheet :-/

Re: What are these nut things called?
 

I know them as Clinch Nuts and RS sell them as such, different to a rivnut which looks like a pop rivet and can be utilised from just one side.

Re: What are these nut things called?
 

This might be of interest.

Andy

Re: What are these nut things called?
 

I should have been more clear.

The self clinching fastners have to be hardened since their serrations deform the sheet to make a firm grip, the various forms of rivet bush will not be hardened.

This is a huge subject with many types of fasteners made for different purposes.