The past few months, I have been using the laser cutter at Copenhagen Fablab to create parts for a Piccolo, "the tiny CNC-bot". Basically, it's a small machine that can move a toolhead freely around in a 50 mm x 50 mm x 50 mm cube. You can attach a pen, a brush, a nail or anything else you can imagine to the toolhead, so there's a lot of possibilities in this small machine. I just finished assembling it and making it work, so I thought I would share my experiences.
(NOTE: You can assemble a Piccolo without any special skills (other than how to work a laser cutter), but if you really want to utilize its full potential, I suggest you learn how to use Arduino (www.arduino.cc), and preferably also Processing (www.processing.org). Both are easy-to learn programming environments.)
Most of the necessary information is available on the project's website, www.piccolo.cc. I'll only share concrete experiences here.
You can find the necessary cutting material at the Fablab. I used 3 mm Acrylic and 3 mm HDF. I made the paper spacers out of some thick paper. It should all fit together, however, the X3 piece is probably too tight - sand it down a bit and it should slide just fine. You might need to do this for other parts, too, but so far, X3 was the only thing I needed to adjust.
The Piccolo team is very specific about screw length and nut thickness. I made do with some M3 10 mm, M3 16 mm, M3 25 mm and normal nuts. You should be able to find them in places like Brinck Elektronik, or maybe Silvan, if you're lucky. A few places in the machine can only fit these 2 mm nuts, but I got it working, either by using glue or simply just by letting the screw sit without a screw.
If you have all the necessary parts, assembly should be quite easy. Just remember not to overtighten the screws since you might need to take some of the parts apart and reassemble them to ensure the best fit.
USING THE PICCOLO
I have had some problems getting the Processing library to work, and as always when you program a physical thing, the machine might not do what you expected it would. Just take a deep breath, go for a walk, and try again.
Thanks to Fablab for providing a laser cutter that I could just walk in and use on a regular Tuesday afternoon(s). That's really something.