Countersunk nuts??

Hey all,

Does anyone know where I could find countersunk nuts? I need to attach two 3mm sheets of aluminium to each other (back to back), and I want to do it with a countersunk 6mm m3 screw, and a countersunk nut (thereby having nothing protruding from either end). Problem is, as far as I can see, the countersunk nut is not sold anywhere. 

I have one from an older (and sadly rare) piece of equipment, and it is 7mm in diameter and 2mm in depth, tapered at what seems to be 90 degrees. There is no "shaft" - it essentially looks like a the head of a countersunk machine screw. No part number or anything.

It seems like an obvious enough thing to want, but I find zero evidence of their existence online...

Any help here would be much appreciated - I can't thing of another way of achieving my goal.

Never seen those. If any friend of yours has a lathe it is not a problem to make one.

Best, M

Good countersunk nuts are hard to find !

What about drilling out a hole that would let you make the nut flush with the surface? A "screw machine" nut is thinner than a normal hex nut. A "panel nut" is even thinner. Or drill and tap the head of a screw.

Also you could make countersunk hole for the screw in one sheet, and then drill and tap the corresponding sheet, so you don't need a nut to start with?

Best, M

Agree with Marik.

Tap the other side. The material thickness meets the requirement for M3.

alexc said:

Good countersunk nuts are hard to find !

Click to expand...

Do you mean "Hard countersunk nuts are good to find"?

http://www.phrases.org.uk/meanings/171650.html

Cam said:

Hey all,

Does anyone know where I could find countersunk nuts?
It seems like an obvious enough thing to want, but I find zero evidence of their existence online...

I can't thing of another way of achieving my goal.

Click to expand...

You may try using a standard c'sunk screw, drill it and tap it. It may be somewhat tricky, and certainly not adequate for mass production.

Try this address. We used their press-in  nuts in top & bottom aluminum chassis panels; the nuts are flush with the surface of the panel.

http://www.pemnet.com/fastening_products/pem-self-clinching-fastener_new.html

Bill Wilson said:

Try this address. We used their press-in  nuts in top & bottom aluminum chassis panels; the nuts are flush with the surface of the panel.

http://www.pemnet.com/fastening_products/pem-self-clinching-fastener_new.html

Click to expand...

I used them a few times. Generally, they don't want to deal with anything under at least 1,000 pcs.

Best, M

mcmasters carr is the place for that type of fitting.  great store on line

It helps to know what it is called.

There is a thing called a weld nut, sounds like what you are looking for.

It's called a "captive nut". You can type "PEM nut" in the McMaster search and they come up.

PEM nuts are pressed in with splines on the outside are they not?

What Cam described is more of a conical item with threads on the inside, and no edge... I don't really get how it "grabs" though.... Cam... are there splines or ridges or any type of machining on the face of the angle that meets the countersunk face?

Right, a PEM nut is not what the OP is looking for.