Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com
> Hello, I noticed that laminators are being used for pcb's, but how 
> reliable are they when it comes to doing double sided images? I was 
> thinking if using two heating plates and "sandwiching" the copper 
> clad with the images would be better? There should be less mis-
> alignment because there is no movement. Any ideas? Thanks, Genaro M.

Nearly all my boards are 2 sided.  Alignment isn't nearly as 
difficult as it may seem.  If you put some alignment marks on your 
carrier paper and can see them with bright backlight, you can get the 
pads to line up.  I use a glue marker to fasten one edge of 
the "sandwich" and put the pcb in between.  Insert the bound edge 
into the laminator first.  Even on my Royal Sovereign NR900, the 
toner "tacks" down on the first pass.  They don't move and missalign 
in the additional passes.  I normally use 40-20 mil vias pads and 
they line up pretty well over 95% of the time.  The only problem I've 
had is if I got carried away with the glue.  One time I got some glue 
on the outside of my sandwich and stuck the paper to the laminator 
roller.  Even the small skew possible by the board thickness (paper 
might be pulled slightly to the top or the bottom) turns out to be a 
non-event.  The paper/pcb tends to align get centered when initially 
put into the laminator rollers.

http://myweb.cableone.net/wheedal/pcb.htm
http://myweb.cableone.net/wheedal/pcbconstruct/cpu3_7b.jpg
is a 2 sided cpu board with a lot of @$&%*#!! drilled vias.

As far as pressure plates, that should work in theory.  I think in 
practice it may be difficult to get even pressure.