11 May
2021
11 May
'21
10:29 a.m.
Date: Mon, 10 May 2021 10:15:34 -0700
From: Vincent Slyngstad <vincent.slyngstad at
gmail.com>
To: cctalk at classiccmp.org
Subject: Re: QBUS/UNIBUS card handles
Message-ID: <826ef016-3060-e690-de81-8209479712e9 at gmail.com>
Content-Type: text/plain; charset=utf-8; format=flowed
On 5/10/2021 9:25 AM, Fritz Mueller via cctalk wrote:
Resin casting will work, but it's messy, etc. I haven't had any trouble
with the toughness of 3D printed handles. Honestly, I often attach them
with a pair of small zip-ties instead of rivets, and they are still
plenty strong. The usual caveats about 3D printing apply -- just don't
print it so that the layers will be torn apart when you pull on it!
Maybe you PDP-11 guys are more used to hex cards, or something? I did
have some PCB made where the card fingers tended to bind, but that's
best addressed with some careful filing and a tweak of the CAD files for
the next run :-). (The CAD files on so-much-stuff have long been
tweaked for a good fit to the connector blocks.)
Vince
Vince,
I recently had Shapeways 3D print some of your card handles in Nylon 12.
They call Nylon 12 ?versatile plastic? on their web site and they use a laser sintering
process for fabrication. I used the card handles on my QBone and UniBone boards
which makes them MUCH easier to insert and pull. The Nylon 12 seems to be
quite tough and I used 3mm x 6mm long screws to fasten them. Shapeways
charged $5.00 each plus shipping to make them.
Thanks for the great 3D design!
Best Regards,
Mark
On May 10, 2021, at 7:14 AM, Joshua Rice via
cctalk <cctalk at classiccmp.org> wrote:
I would assume it would be trivial to do an injection-moulded run of these handles...
They might also be ideal for silicone mold / resin cast, for smaller/home production
runs?