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[VE7RF]

Has anybody here ever used ..'PEM NUTS' ??  I have zero experience with them. Rich Measures, AG6K (SK) was a big advocate of pem nuts. But I never followed up on it. 
It would seem to be an eloquent solution for some applications.

[KD6VXI]

Yes.  On my skateboard as a kid.  They are flush mount and work easily on plywood decks.

On rf decks you require precision cutting of the hole.  Too small and they don't go in.  Too big, they fall right out.

There are other solutions.  Check McMaster Carr for captivated nuts.

--Shane
WP2ASS / ex KD6VXI

[WA9AFM]

Sometimes called 'clinch nuts' or 'self-clinching nuts'.

[W1VT]

They are easy to use with the right equipment and work well.  I use a sheet metal bender to press them into sheet aluminum.
They come in different materials.  I used the aluminum ones to avoid dissimilar metal issues.

[N2SR]

Have seen them in use since the 1980s. 

First saw them used to supply +Vdc to the high power solid state 1 kW RF boards. 

The FR4 boards had the correct size hole, and the Pem nuts were pressed into the boards, then soldered to the trace.  #8 PTFE wire was used to supply +48 Vdc to each PA module.  Idc was between 35 and 40 amps. 

[W6QW]

Clinch nuts, for which PEM has been a long standing manufacturer, are a mainstay for many of my chassis projects.  The key is to use the exact clearance drill per specification.  Although I use a hydraulic press, you can use a standard arbor press or even vise-grips for soft metals. Buy yourself a handful and play around with them.  I think you'll like them.

[SWMAN]

 I knew a couple of nuts like that back in my younger days.

[AC7CW]

They can be tapped into aluminum with a light hammer. Not sure how long they stay in place when done like that since a press is recommended but I saw that done by a owner of a sheetmetal shop...

[WA2CWA]

Been using PEM's for many of my home brew projects for many years. I also have the stand-off PEM's too. Arbor press works well to get them secured and even a good strong vise works too. Tight spots into aluminum can work with a flat punch and hammer. PEM's also comes in various sizes depending on the thickness of metal you want to insert them in. I think my stash goes from #4 to at least 1/4 inch sizes.

For light reading, you can download their 275 page catalog:
https://www.pemnet.com/catalog-downloads/
You can even request samples  as log as you don't go crazy with the request.

Pete, wa2cwa

[N1UK]

We used them at REL in England in the 80's. You just had to be careful not to push them out when screwing panels back together. They held up well otherwise


73 Mark N1UK

[KD0REQ]

limited usage, but they're useful. pressed into aluminum with a Vice-Grip plier.

[W1VT]

Properly installed, they were hard to remove.

[KD6VXI]

Properly installed, they were hard to remove.

100 percent.  Properly installed, and not torqued to 1278436198746938541982354 ft pounds in use, they will last decades. 

Henry uses something similar in their rf generators.  I've taken a couple of them apart a LOT of times (I have an 8877 and a 3cx3000 converted generator.  I use them to test tubes easily).

--Shane
WP2ASS / ex KD6VXI

[KW6LA]

Hi Jim, long time.  PEM nuts are one way nuts and work well. If installed on the wrong side, they can come loose.
You can clinch them using a nut and bolt also, if you dont have a press. Know there are other options like Rivet nuts and nut plates to name two.   Just used them on a project 6 months ago.  Good luck with your PEM nuts .