Homebrew PCBs

On Tue, 15 Nov 2016 20:23:55 -0800, you wrote:

>Thanks Dwayne.  The phenolics I've looked at online (mostly ebay) are as you
>say, brown.  I'm curious how we arrive at a green color like the originals I
>have.
>
> 
>
>The color situation has been most frustrating - pictures are not reliable of
>course - on websites I see what looks like almost the exact color but in
>samples it's completely wrong.
>
> 
>
>When you speak of dots and tape, you're referring to prototype boards or
>production?


Twice (or 4x) black crepe paper tape and black dots on acetate,
photographed onto Kodalith film (reduction to life size) used as a
master negative for photoetching.

For dual side boards, they had a red and blue transparent tape that
was photographed with panchromatic film (not ortho), and illuminated
with the complementary color of light.

There's a very distinctive style that dates the boards.  

Can be used for prototypes or production, since it depends only on how
many you want to make.

Harvey
>
> 
>
>From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] 
>Sent: Tuesday, November 15, 2016 9:41 AM
>To: Homebrew_PCBs@yahoogroups.com
>Subject: Re: [Homebrew_PCBs] Dyeing PCBs for a vintage look
>
> 
>
>  
>
>Many of the old PCBs were made with phenolic PCB material.  The color varies
>between brown to various shades of beige.
>
>You can still purchase bare (blank) copper-clad phenolic PCB material.
>
>Another characteristic of old PCBs is that the layout is often done by hand,
>using crepe dots and crepe tape in various widths.  Even earlier layouts
>were strictly hand-drawn - no tape or dots.
>
>dwayne
>
>
>At 01:08 PM 11/12/2016, 'Brad' unclefalter@...
><mailto:unclefalter@...>  [Homebrew_PCBs] wrote:
>
>Hey guys,
> 
>I have recently heard of some methods of 'dyeing' PCBs to achieve coloration
>closer to what vintage PCB stock looked like.  I'm wondering if any of you
>have experience on this, what works, etc.
> 
>I recently acquired some original, untouched Mark-8 computer boards:
>http://bradhodge.ca/blog/?p=826
> 
>I'm hoping to use them to help create replicas.  But I just can't get the
>PCB to look the way I want.  They look too modern.   I've heard dyeing can
>help, and that one can even fake the fab house marks somehow.
> 
>I'm surprised there isn't a stock of vintage copper clad out there
>somewhere.  Seems to be vintage everything else these days in electronics.. 
> 
>Brad
>
>