30-pin SIMMS

From: jpero_at_cgocable.net <(jpero_at_cgocable.net)>
Date: Sat Feb 27 21:07:18 1999

Date sent: Sat, 27 Feb 1999 21:39:20 -0500 (EST)
Send reply to: classiccmp_at_u.washington.edu
From: Max Eskin <max82_at_surfree.com>
To: "Discussion re-collecting of classic computers" <classiccmp_at_u.washington.edu>
Subject: Re: 30-pin SIMMS
Originally to: Discussion re-collecting of classic computers <classiccmp_at_u.washington.edu>

> On Sat, 27 Feb 1999, Allison J Parent wrote:
> >that config the 1meg parts started to be common. Sipps were out os use
> >by
>
> Why did people stop using them, and why didn't people start off using
> SIMMs? Isn't a SIPP basically a SIMM with pins attached to the bottom?
>
> --Max Eskin (max82_at_surfree.com)

Triple reasons:

Manufacturing turned sockets or (shitty sprung leafs like the IC
socket) is more expensive and more problemic. Lastly, trying to
install or pulling SIPPs usually result in bent pins.
Adding pins to already SIMM's design adds expense in extra parts
and solder, labour.

So we hail on SIMM's and DIMM's with vigor.

Manufacturing regular simm slots, contacts all like cookies,
stamped out of workhardened sheet. Punch, punch, punch! And it
does over 1000's a minute. Then plated tin or gold depending on
quality and some crass cheapiest ones used softer metals. Yeech.
Those plastic socket bodies are simply one time molded and all
the metal parts simply pressed or snapped into and do many real
fast.

That it.

Punch machines can be size of a largish dorm fridge and it's totally
mechanical spun at high speed with a 2 or 3 HP electric motor to
punch out small parts up to 2" in area.

While you have some dud parts, spend your time pulling those
sockets of all types apart, Sometimes it comes apart by heat.

Screws are born from roll of wire. Liberally sheared to length, rolled
to form threads (not cutting), head mushroomed by a mold under
pressure. That is why always can tell the heads is bit off center
and sometimes mal-formed. Ditto on scale of number of screws
made per minute, 1000's no surprise.

Some get plated some painted.

Quality screws are fully formed, no burrs, smooth.
Crappy ones always chews out the holes and softer.

Still have one screw that is threadless with fully formed head, found
it when I was working on a PC. :-( )

Wizard
Received on Sat Feb 27 1999 - 21:07:18 GMT