I constructed most of a 3D printer using the exceptional plans posted on Thingiverse based on the OpenBeam system. The link for the plans is here: http://www.thingiverse.com/thing:41967. The parts were printed on a Replicator 3D printer. Timing belts were ordered from beltingonline.com (T2.5 Standard Breco® Open Length Timing Belt, 6mm width, 2m length, Standard 590 White polyurethane, steel cables) as were timing gears (25 Tooth T2.5 Pulley, 5mm bore, 1off M3 Grubscrew Holes). I purchased linear shafts from McMaster (10mm, part number 6112K47 and 8mm, part number 6112K46). Couplers for the z-axis were purchased from ebay, while acme screws were purchased from TechPaladin. I installed limit switches on the front for the y-axis and on the right carriage for the x-axis. Currently the "tool" is simply a sharpie pen.
The electronics wires were soldered onto an Arduino breakout board fitting over a Dueminalove. Power is provided by an old ATX power supply onto which I jury-rigged a power switch (ATX supplies are normally turned on/off by the motherboard of a computer).
I wrote a custom interface using the Processing language which allows me to move the pen between two points. If the pen is down, the software connects the two points with a line to mimic what should be happening on a real piece of paper. The video below shows the interface in action.
Link to Arduino Code
Link to Processing Code
A first demonstration of the 3D plotter can be seen in the picture shown at right. The left shows the Processing interface, while the right shows the actual paper which was drawn. The resemblance demonstrates a good proof of concept, although the interweave is apparent by kinks and changes in slope in what should be straight lines. This is a bigger problem than I anticipated and one I will have to work to fix.
My longer term goal is to mount a frosting extruder in place of the pen and use the Processing interface to allow custom decoration of cookies or something similar which could be placed on the platform.
