Homebrew PCBs

Steve wrote:

> Yes, let us know!
> 
> I had barely useable results using inkjet transparency in a Lexmark
> 4029 600dpi Postscript laser. My theory was that the inkjet coating
> would dissolve in water and the transparency would allow me to see
> when I'd successfully pressed.
> 
> In fact, it was impossible to get water all the way under the
> transparency and since the toner is not transparent I could not really
> tell when it was successfully bonded to the copper.
> 

   You do not need the coating to desolve to get results.  Send the page 
back through the printer an extra time or two, printing nothing.  Extra 
fusing gets better toner/coating bond.  A good ironing and the toner 
sticks, and smooth slow peeling under water the coating will simply rip 
at the edges of the traces.  I'm peeling within 30 seconds of getting it 
wet, slight softening of the coating but I'm not sure that's long enough 
to think of it as disolving.

   And you don't want it to disolve.  Disolve and it comes away from the 
paper as well as the traces, and that's why it leaves coating in the 
holes and between close traces.  You want it to peel well, and peel away 
all the extra coating material, not disolve and leave coating on the 
board.  My own boards are far improved since viewing it this way..

Alan