Stereolithography Stereolithographic printers are much different than the more common extrusion-type printer. These printers use a clear vat of photosensitve resin. The vat has a DLP projector underneath and a flat build plate on the top. The printing process begins by the build plate moving to the bottom of the vat. The projector then shines an image, of the first layer of the object to be built, into the vat. Because the resin is photosensitive, it hardens as soon as it is exposed to the light from the projector. The build plate then moves up a very small amount and the next layer is shined upon the resin. This creates the next hardened layer of the object. The process repeats until the object is fully constructed. These printers are more expensive than extrusion printers and consumer models start around $500 at the time of this writing. One high school teacher however, has reportedly built a homemade SLA printer out of $20 worth of parts along with the cost of an LCD projector. ---Table here--- Advantages and disadvantages