Homebrew PCBs

Today I tried 4, 3, 2, and 1 - I didn't expect them to work as I knew
the film wasn't laminated well enough, so I merged the four into one
print (one quadrant per size).  The print for 1/1 was pretty much
solid.  The print for 2/2 had moire patterns all over it.  The 3/3 and
4/4 were printed well enough to expose the mask reasonably.

I reduced my exposure from 5.5 minutes down to 4, but still the traces
were wider than the gaps:  http://www.delorie.com/pcb/djspirals/

I *think* with some tweaking of the print widths and exposure, I
should be able to do 3/3 rules.  As usual, the reason behind obtaining
such results is to make the 5/5 or 6/6 boards that much more reliable.

I'll probably make a test print by hand with specific width/gap sizes
in printer pixels to see what the printer's limits are.  Also,
exposing through a step gauge might help understand what exposure time
is best for such fine traces.