Homebrew PCBs

The transparent is already deformed when passing thru the fusing unit of the printer and the
the deformation are not regular. For exemple, the corners align well while the top center is too low, the center is on the left and the center bottom is on the right... and so on.
Different print give different deformation positions.

--- On Fri, 7/4/08, DJ Delorie <dj@...> wrote:
From: DJ Delorie <dj@...>
Subject: Re: [Homebrew_PCBs] double sided PCB, accuracy
To: Homebrew_PCBs@yahoogroups.com
Date: Friday, July 4, 2008, 4:07 PM










    
            

Michel Baguet <bagmik@yahoo. com> writes:

> Well, line up is not a problem. it's the transparent getting

> deformed when heated.



Ah, that.  What I did was calibrate the deformity once (transfer a 3x3

square to a board and measure it) and compensate for it in PCB.  To

align two sides, I ended up using targets centered on the sides of the

board, rather than diagonally opposite.  Also, I've tried using a hand

iron to tack down the paper before laminating it.



Photomask is easier because there's no heat, you can see through the

paper to line it up, and nothing moves during the exposure.


      

    
    
	
	 
	
	








	


	
	


      

[Non-text portions of this message have been removed]