Homebrew PCBs

Hi,

I have been experimenting with inkjet printing and have come up with a
system that works for me. I recently printed 20 boards with 12 thou
track/gap and had no track breaks or shorts.
I have a Lexmark Z25 printer and a home-made light box using 4 x 12W tubes.

Print on to JetStar film with the printer set to maximum quality, photo
paper, using original ink. This puts on so much ink you can actually feel
the tracks if you run your finger over them.
Use Mega Electronics Microtrak board and expose for 5.5 minutes (this will
vary, depending on your light box).
Develop in a tray, tipping the tray backwards and forwards until there are
no more streaks of resist coming off the board. Rinse the board then dip it
in the etch tank tank, remove it immediately and rinse again. The areas to
be etched will now be stained by the etchant so it is easy to see if the
board has exposed correctly and all unwanted resist has been removed.

If all is well then etch the board.

The make of board is important. Microtrak seems to be very tolerant of poor
contrast artwork or incorrect exposure times. If you are having problems
getting a good result it may be worth trying a different make of board. The
quality of the resist seems to vary quite a bit between different makes.

The film came from Rapid electronics http://www.rapidelectronics.co.uk Order
number 3041500 for a pack of 10
The board comes from Mega Electronics http://www.megauk.com I had trouble
using their Fotoboard2 but the Microtrak seems to work well.

I hope this info may be of some use to someone.

Les