Homebrew PCBs

An update:  Heads cleared, up and working - Windex on the park head
for a day worked wonders.  No more isopropanol!  In fact, I've found
if I use IPA to clean the copper, it causes blotching.

But another question - I'm getting random large drips off my print
heads, leaving big splotches in my circuits, and I don't get even ink
coverage - the first part of the board to print has thinner ink than
the later parts, which is quite heavy and well defined..

Any one else get drips???