cnc74 wrote:Reading the specs they are using a class 1 blue-ray type laser
A Class 1 laser can not even harm an eye, even when viewed directly with typical optical instruments. If it doesn't cut retinas, I very, very seriously doubt it can cut 1/4" plywood.
Optical drive lasers are Class 3B, and nearly anything over 0.5 W (which can cut thin black paper, slowly) is Class 4.
I would be very wary of giving money to people making a laser cutter if don't know their laser safety classes.
The GlowForge is based on a traditional carbon dioxide laser tube, but the cooling system is contained within the enclosure (no external water pump, tank, or bucket).