Front Panel Tech Note 2

[Vincent Slyngstad]

From: Kyle Owen: Monday, June 15, 2015 6:17 AM
>> PS: If a way is developed to make the plastic levers, the 11/20 uses the
>> exact same part, just in PDP-11 colours.
> 
> They've been 3D printed with the sintered nylon process, dyed and polished
> with good results thanks to the efforts of Vince Slyngstad. I'm not sure if
> Vince also did the model of it or had some help, but I'm quite satisfied
> with mine mechanically speaking, though the yellow is a little light for my
> 8/E.

I tried spraying a white Nova 3 handle that I had printed with the same 
process with Krylon Fusion yellow.  That gave a slightly less "bright" 
yellow with a good satin finish, and the handle hasn't melted down 
into a smelly mess, as I gather can happen with some paints.  (And 
is also why I did this with the Nova 3 prototype handle that didn't 
fit well anyway.)

It was actually even quicker and easier than sealing the yellow or 
orange porous sintered nylon with urethane floor polish.

> Maybe some of the 11/20 colors would turn out better.

I don't like the Shapeways dye colors for the -11 colors, though 
I suppose if you did the whole panel it would look OK.
(The "pink" is sort of the right magenta, but much too bright.)

I'd probably just print them in white (slightly cheaper too), 
then look for a suitable spray paint.  Since the surface is so 
porous, I don't think there'll be the problems with the 
paint failing to bond that a non-porous plastic would have.

Designs can be found here:
http://www.so-much-stuff.com/pdp8/cad/3d.php
though the commentary is slightly out of date, as usual.

    Vince