Homebrew PCBs

On Thu, 01 Feb 2007 19:35:37 +0100, Lez <lez.briddon@...> wrote:

> Ok I am seeing the same problem with this 'working' paper as my other
> papers, and now I'm on a laminator, not an iron....
> My problem is when I heat the paper/toner onto the board, all looks
> fine, as the board cools, the paper 'bubbles' up in some areas.
> This is more noticeable on larger (say 6*5inch) boards than smaller,
> say 3*3, on the smaller sizes, the paper sometimes just 'pops' or
> lifts off.
> Am I the only one suffering this?
> It cant be too much heat, the new laminator is so 'warm' its not
> melting the toner properly, but I still see the expansion.
> I'm on a thick (1.6mm?) fibreglass board
> I thought it was my water was too cold and was a 'shock' to the board,
> but just letting it air-cool is causing it also.


I see something similar with my paper, it tends to rip off the board  
outline if i do not draw a second, wide, outline around it to anchor the  
paper to the board. I always thought the paper is shrinking and causing  
the problem this way.

You can try several things. Run the paper through your laminator a few  
times before use to "set" the size.
After printing, scratch the back of the paper with sandpaper or a brass  
brush to open the surface and allow water faster access.
Draw a wide outline around the actual board outline to guard it. Use  
another paper.

I throw the boards into water still hot, but i have also let it cool with  
the same result.

ST