Front Panels - PDP8 and PDP 11

Rod Smallwood rodsmallwood52 at
Wed Mar 2 16:32:36 CST 2016

Hi Guys
               Having got  8/e (A & B)  plus 8/f and  8/m into 
production its time I made a few comments.

The aim has always been to reproduce the original panels using the 
process DEC used all those years ago.
Needless to say we had to go through the learning curve with only 
photographs, scans and one 8/m original
panel to go on.

In the interests of origiality I have kept what we used call 'features' 
as found in the documentation and the sample we had.
I'm trying to reproduce the original, not produce an improved or fixed 

The only process deviations I have allowed myself are as  follows:

     1. The original versions would have been drawn twice full size by 
hand on matt paper in indian ink.
          One sheet per colo(u)r would have been requred. They would 
then have used a process camera
          to reduce to one to one positive masters on clear acetate film.
          The cameras (they were huge) and the darkend rooms they worked 
in no longer exist.

           I used to do just that in the early '70's but whats weird is 
where I worked is less than 50 yards
           from the silk screen studio doing the work now.

           Now I use Inkscape and its layers to do the same thing. The 
screeners have an Epson printer
           the size of a piano to print my layers in black onto clear 
film. After that the process is the same as it was.
           They take a fine meshed cloth streched onto a frame. Its 
coated (by hand) with a photo sensitive
            emulsion, when dry it gets exposed through the master using 
a UV light source.
           The the parts proteced by black on the master are water 
soluable and get washed out  and hence
           let the ink through. So one screen per layer is required

2.      DEC would have printed the images first and routed or milled the 
holes using some kind jig later.
           As long as the hole stayed inside the white line that was 
deemed to be OK.
           We drill (laser cut) first and screen afterwards.


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