There are 2 main consumer grade 3D printer types. Flament and resin. Printers like the Makerbot and the Ultimaker use filament, a plastic wire which gets extruded through a hot end which draws several 2D layers on top of one and other. This takes a long time and can be rough depending on what filament your using , the size of nozzle etc.
Resin or SLA based printing is a similar process but instead of extruding it cures photo sensitive resin which moved up or down every layer and a laser or DLP projector to harden the liquid.
I found this really cheap DIY printer.
Andarduino (Mega?) + motor driver board (ramps)
cd/dvd Player parts
3d printing Resin
other builds online :
tips video on ramps:
sprinter : arduino firmware : http://reprap.org/wiki/Sprinter
printing software: creation works :http://www.buildyourownsla.com/forum/viewtopic.php?f=5&t=2597
Matrial: resin : ftd : http://funtodo.net/our-3d-resin-properties.html
resin : makerjuce : http://www.imakr.com/en/resin/67-makerjuice-g-500ml.html
Make your own resin , dono if it works:
Stuff to do :
Find schematic for connecting motor driver board to arduino and motor.