Homebrew PCBs

Back in those days I used two methods:
Copper clad FR4 was available, but a lot of SRBP was used as it was much cheaper.
The first method was to paint, by hand, using mothers thinned nail varnish onto a carbon paper print traced from the layout printout.
There was a great negative photo resist, KPCR, made by Kodak, sadly no longer available that you exposed to ultra violet light through a negative transparency of the of the layout.
Then developed in a solvent based solution that coloured your fingers red for at least a week if you got it on them.

So you would not be cheating if you used modern pre-sensitized copper FR4 from companies such as Mega,
<http://www.megauk.com/pcb_laminates.php>
or a dry film:
<http://www.instructables.com/id/Fantastic-Double-Sided-PCBs-at-home-using-photores/>
or
<https://www.youtube.com/watch?v=cRCFGZxmob0>

Malcolm

I don't suffer from insanity I enjoy it!
Mene, mene, tekel, upharsin
The writing is on the wall.
Ha-ktovet al ha-kir

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On Tue, 9/29/15, 'Brad' unclefalter@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

 Subject: [Homebrew_PCBs] G-10 questions
 To: Homebrew_PCBs@yahoogroups.com
 Date: Tuesday, September 29, 2015, 11:51 PM
 
 
  
 
 
 
   
 
 
     
       
       
       Hi guys,  I’ve been continuing to
 research and amass parts for my TV Typewriter replica build.
  I have a blog of it here: http://bradhodge.ca/blog 
 -- mostly working on the case right now to inspire me to
 push forward, but I’ve succeeded in getting almost all of
 the vintage 1973 or earlier chips I needed.  Now I’m down
 to the PCBs again.
  I guess I’m still
 kind of ‘green’ on this sort of thing.  Ideally, I’d
 like to do my PCBs the way they would have in 1973.  But I
 still don’t understand how that worked.  Don Lancaster
 said the boards used were green G-10.  I found this on
 ebay:  http://www.ebay.com/itm/16-Green-G-10-FR4-Sheets-032-Thick-x-28-x-7-25-G10-Material-/141719358328?hash=item20ff21cb78  I guess what I’m having trouble
 with is understanding how a home PCB maker in 1973 would
 have gone about getting copper onto these boards and copying
 the artwork from the article.  Is there any really good,
 baby-steps reading out there?  I just want to understand
 the original process and if it is possible to replicate it
 here in 2015.  I sort of understand the idea behind photo
 lithography.. I’m just not understanding how copper ends
 up on board, etc.  Much appreciated!  BRad     
 
     
      
 
     
     
 
 
 
 #yiv0643880995 #yiv0643880995 --