PDP-8/e front panels.

[Rod Smallwood]

The switches were made by a company in the US called Stackpole They 
still exist.
The switches are marked Patent  3217112
  They are a normal slide type modified with a U bracket to allow
the attachment of a lever arm to operate the switch when toggled up and 
down.
They come in three types ;  hold up or down to connect and close to connect.

The lever arms are molded  from a tough type of plastic (nylon or PET ?)
They have maintained their bright colour over the years suggesting a  
tightly bonded structure.

There appear to have been attempts to produce copies but the only results
I have seen, have been disappointing.

3D printing looks hopeful but not for production quantities,
The tooling for injection moulding (thats how they were produced back in 
the 1970's )
is too expensive.

At this time I'm just doing replacement panels for 8/e's and maybe other 8's
Long term a light weight  resin bezel and maybe (very maybe)
  a lamp and switch panel + microprocessr to emulate a real 8.
But only if the switch sourcing problem is solved.

Rod Smallwood (Newbury England)



On 07/06/2015 14:13, Noel Chiappa wrote:
>      > From: Rod Smallwood
>
>      > I have recently produced a number of high quality custom PDP8/e front
>      > panels.  They are full size reproductions of the original. The
>      > production methods are exactly as used in circa 1971.
>
> First, my sincere congratulations! This is a real contribution, and I doubt it
> was trivial to accomplish.
>
>      > I'll also instigate another batch of ten. .. If I get orders for more
>      > than ten then I'll bump up the second batch size accordingly.
>
> These sound so cool I'm tempted to buy one, even though I don't even own a
> PDP-8! :-)
>
>      > If there is a demand I'll do other 8's or 11's front panels that use
>      > the same plexiglas and silk screen technique.
>
> Someone mentioned -12's and -15's?
>
> I don't (yet) need any -11 ones, although at some point, I might need an
> 11/20 one (I have a line on an 11/20 that spent a lot of time outside, so its
> front panel is sadly very faded).
>
>
> The thing we really need to find now is a source for the special switches
> that DEC used in the front panels of the machines of this generation.
>
> Electrically, they are just standard SPDT switches (usually two-position,
> although for some - e.g. Deposit/Start - they are momentary-contact
> spring-loaded); the real issue is the mechanical fastening, which uses a
> special front plate (albeit on a standard micro-switch body).
>
> I have a number of different ones in my machines, from various manufacturers,
> but I have had no luck tracking down new ones through the part numbers on
> them (they seem to be DEC part numbers, or adaptions thereof). I have asked a
> number of people, but nobody seems to have spares/extras.
>
> Anyone know of a source?
>
> 	Noel