3 Sep
2014
3 Sep
'14
10:35 a.m.
Very cool project, I've got several 8's that I can provide photos of if
that would help (8/e , 8/f, 8/m). I've been looking at a similar project
with my 3D printer but rather than re-create the PDP-8 switch handle
directly, build a switch handle that would work with modern (and
inexpensive) tactile buttons. My goal is to have a way of creating an
arbitrary front panel.
From my experience you will want to injection mold
these switches as the
variability between printers would probably render parts of
one switch on
one printer from not working with parts printed on a different printer.
Such is the newness of these things.
--Chuck
On Wed, Sep 3, 2014 at 8:27 AM, Jack Rubin <j at ckrubin.us> wrote:
I'm in the process of reproducing front panels
for PDP-8/E and/or M
machines, as well as switch levers for these machines and others that use
the same shape but different colors (e.g. 8/L, 11/20).
For the front panels, I'm working with a local (Chicago) silk-screen house
to create the reproductions. At this point (still exploring final pricing),
it looks like unit cost will be about $200 for a run of 5. This will most
likely be a CNC cut acrylic panel (laser probably won't work because of the
angled relief for the key switch) with silk-screen printing front and back.
The panel shape is the same for E and M but the screens are quite
different. I've also got a couple different M variations. Note that each
panel requires five or six screens, including black masking on the back and
transparent red or "frosted" masks for the indicator lights in addition to
the three colors on the front.
I'm not sure about possibly adding a transparent overlay (non-original)
over the front silk screening to protect the final product. Please let me
know your interest and thoughts about a protective overlay.
For the switch levers, "phooky" from the NYC Resistors has done a 3D
rendering - http://www.thingiverse.com/thing:360853 - and printed
prototype levers and mounting frames. Note that there are three renderings
at the thingverse site - original lever, lever with improved pivot (metal
pin) and bracket for attaching lever to available slide switch. Phooky has
also printed up samples of these objects. The next step is to work on
injection molding the parts. The Resistors have an injection molding setup
and phooky is planning to create a mold using CNC equipment and his 3D
renderings. There are several reasons for moving from 3D printing to
injection molding for these parts. The first two, finish and mechanical
strength, are slowly being addressed by improved printers but the third
reason, color matching, is the critical difference.
The front panel project is in progress and hopefully panels will be
available in a few months.
The switch project is very much exploratory with no promises or dates at
this time.
Comments please!
Jack