On Tue, 13 Oct 2009 20:53:10 +0000 (UTC), "John B"
wrote:

Jim Thompson scrobe on the papyrus:

.
.
.
Up one drill size plus cutting oil did the trick. All 24 holes now
tapped ;-)

...Jim Thompson

I don't know if you can get these on your side of the pond, but I used
to get through tens of thousands of them every year.

http://www.avdel-global.com/en/produ...hin-sheet-nuts
ert.html

I have used something similar to the superserts.

Usually, a shop would swage a PEM on, and it would be tight, but that
same PEM is hard for the home shop owner to get in tight, so a hand
crimped version (several) had to be made. I know the 1/4 - 20 is
available but never used it. Ours was 1/4" hole, and drop in the insert
already threaded onto the swaging tool. and squeeze. The tool swages the
insert in place very tightly. The stuff was passing CSA back when they
threw things off their dock platform to 'test' it.