On 08/30/2010 06:41 PM, Chris wrote:
> forget the dry film for reliability.
I've figured out how to laminate the dry film with nearly 100% success.
I have two ways - wet or dry.
Wet
---
Similar to Adam's method, I put the film stick-side up on a plastic
sheet, rinse, and flip the sheet over onto the PCB. This lets me
squeegie out the water without actually touching the film (the plastic
sheet protects it). Once most of the water is squeegied out, I run it
through the laminator set to 200 F (96 C) - below the boiling point of
water, so no steam bubbles.
Dry
---
Get a clean sheet of paper a bit bigger than the PCB, plus a few inches
more sticking out the top (the edge that goes into the laminator first).
Put the PCB on it. Cut some film as wide as the PCB and 1-2 inches
longer. Tape the leading edge of the film down (stick-side towards
paper) just ahead of the PCB. Cut two 2" long strips of paper, tape one
to each trailing corner has handles.
Put the assembly on the feed side of the laminator set to 240 F and get
it started. Once the paper is grabbed, pick up the paper handles and
lift the film off the pcb, pulling gently back and apart. This makes
sure the film first touches the pcb at the roller, so no air can be
trapped. The handles also let you put tension on the film right up to
the moment it goes through the rollers.
(hmmm, I wonder if I can just put the board through upside-down so
gravity keeps the film off for me)
In both cases, for double sided I just repeat on the other side.
The Dry method doesn't work on aluminum foil (for solder paste
stencils), but I've yet to try the wet method with it. The foil itself
wrinkles on its way through the laminator, hopefully the wet-stuck film
will help keep it straight. Maybe I'll tape the foil to a carrier too.