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From: wbrown@beva.bev.lbl.gov (Bill Brown)
Newsgroups: sci.electronics
Subject: Re: plated thru holes
Message-ID: <5714@helios.ee.lbl.gov>
Date: 30 May 90 20:00:50 GMT
References: <1109@uvicctr.UVic.CA.UUCP> <1114@uvicctr.UVic.CA.UUCP> <1422@marlin.NOSC.MIL>
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Reply-To: wbrown@beva.bev.lbl.gov (Bill Brown)
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X-Local-Date: 30 May 90 13:00:50 PDT

In article <1422@marlin.NOSC.MIL> herman@marlin.nosc.mil.UUCP (John W. Herman) writes:
>
>--
>I vaguely recall seeing an ad for a machine that puts sleeves in
>PC board holes the claim being that the sleeves could be put in
>for much less than plating through holes.  I only remember seeing
>the ad and not much else.
>-- 

---And round and round it goes....

'Way back in the Jurassic age, BPTH, (Before Plated Through Holes) eyelets,
AKA rivets were used for making connections between the two sides of a
double-sided board.  They were sort of squashed or swedged into place, which
was supposed to make a permanent connection.  Of course they usually became
intermittent over time, perhaps due to working caused by thermal expansion.

The next step was to solder the rivets to the artwork.  Eventually, this also
failed intermittently, probably for the same reason.

Usually, we ended up running wire through the rivets which was then soldered
to the artwork.  Seems like we ued #24 soft copper, as best I can recall.

You've never lived until you've tried to trouble shoot a fair sized system
(in those days a few thousand gates built out of discrete components, six
2-input nands per board) full of rivets which sometimes conducted and sometimes
didn't.

Rivets.  Bah!  Humbug!!  Might as well use wire in the first place.  Be sure to
make gentle bends in the wire on either side of the board, and leave a tad-bit
of slack for expansion/contraction.

							-bill
							wlbrown@lbl.gov

Disclaimer:  These opinions are my own and have nothing to do with the
    official policy or management of L.B.L, who probably couldn't care 
    less about employees who play with trains.