Thank you guys. I appreciate the kind words and your encouragements.
Ron, I'm using a 445nm diode with my own design constant-current driver at about 1.1 amps. I think I could increase the power some, but at about $50 US per diode, and having already blown one diode while experimenting, I'm inclined to leave it alone for now.
I use a small blower to keep smoke from interrupting the laser beam, but at the suggestion of a poster in another forum, I will soon add a small compressed air jet to try to remove carbon from the kerf while burning.
I have also found that the laser is much less forgiving of backlash than when routing, so I will soon rework the Y axis to replace the present bronze bushings with linear ball bearings.
Happy New Year All,