How small could you go if you cut away the background and left the letters stand out? Small stuff like this would be great for some decorative scrollwork on pocket watch cases and guns, etc.

Tweakie, that a nice nickle you have, those usually don't have the date on then anymore. Where are you going to get any checkers that small?

Tweakie, in case you need some any extra checkers, here are a few:

.   .   .   .   

RICH

Come on Rich, there is only eight there and you know I need sixteen. 

Tweakie.

LOL @ Rich. Don't forget the red ones.
. . . .

There is an interesting abnormally with the 0.5mm x 0.5mm matrix in so far as the dot size is smaller than I can cut a hole in a piece of kapton. It would appear that as the center of the beam contains more energy if you fire it quick enough you can get a smaller dot size. Strange.

No, that is normal for a stock laser beam. It's called a Gaussian distribution. Commercial laser-cutting machines often have some expensive beam-shaping optics to convert that into a flat-topped distribution, which makes for better cutting in heavy metal at a commercial scale.

cheers

Here are some tests I did engraving HO scale bricks in plastic sheet.

Hi kregan

Looking good. 

You seem to be getting a turn-on (or turn-off) delay looking at the dots on those short lines ??

Tweakie.

I think it is a limitation with my machine accuracy.  That was done with the spindle
off and just dragging a sharp point across the plastic sheet.