Newbie questions

Hello, I am extremly new to RepRap. I have been doing my due diligence and reading everything I can about the Prusa Mendel variant. the reprap.org site is very informative but I seem to be missing some information. I have a desire to prototype using ABS plastic, but I am not sure if this is the best choice for a newbie. (any other suggestions would be welcome) but I can't seem to find any information about the delivery system for the heated plastic. I am sure I am missing it somewhere, but information on raw plastics, exactly how the extruder system works, or a basic walkthrough at least seems to escape me, I understand the principals of the motor control for x/y/z axes. again just some newbie infor on raw plastic and how the extruder works would be really helpful, if anyone has any links or anything I would really appreciate it. sorry if this is a stupid question.

ABS is one of the two plastics most people use, the other being PLA. There have been many discussions on these forums on the relative merits of both. The reason you don't see much about the actual extrusion on the Prusa Mendel page is that the extruder is considered kind of a separate part. Mendel, Prusa Mendel, Huxley are all designed to take interchangeable extruders. The most common extruder design is some variant of Wade's Extruder. That paired with a variety of hot ends (the nozzle that heats up and the thermal barrier to keep it from melting the rest of the machine) is what lays down plastic. Example hot ends are Arcol hotend, Wildseyed hotend, Adrian's hotend, Makergear hotend. I personally use the makergear hotend but people have had success with all of these.

For almost all of these extruder designs you'll need plastic in the form of a filament, most commonly 3mm but people are experimenting with 1.75mm. A good distributor of filament in the US is Ultimachine but there are many others.

Hope this helps get you started.

Thank you! your information was very helpful!