Homebrew PCBs

Do a test exposure, cover the negative, on a piece of scrap board, and expose a strip for 10 seconds say, move card along to reveal an extra strip, expose and so on.  Develope and chose time that give best result.  In the example the first strip would be exposed for 20 secs and the second strip ten.  Depending on the lamp, wavelength sensity of film and height, the time requie3d can vary considerably.

Write the times on the card as it is easy to forget how many you have done.

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 Fri, 8/19/16, kbyrne10@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

 Subject: [Homebrew_PCBs] First Negative developement Brd
 To: Homebrew_PCBs@yahoogroups.com
 Date: Friday, August 19, 2016, 1:36 PM
 
 
  
 
 
 
   
 
 
     
       
       
       I finally have all the supplies that I
 need and need a question
 answered.SuppliesScotch
 LaminatorOffice depot Black and white
 copier transparencies. Two copies of each experiment
 circuit.Dry film bought in
 ChinaPH up bought on
 E-BayEagle to Gimp
 negativeDakta light bulb approx 12 in
 above frame.Question? How long do I turn
 on light bulb for first experiment in developeing
 board.If it fails to develope properly
 how much time do I add for next
 experiment?What is correct procedure for
 this experiment to learn this aspect properly?
 
     
      
 
     
     
 
 
 
 #yiv3949153176 #yiv3949153176 --