Lyman filament extruder

The Lyman filament extruder is a device for making 3D printing filament suitable for use in 3-D printers like the RepRap. It is named after its developer Hugh Lyman and was the winner of the Desktop Factory Competition.^[1]

The goal in the competition was to build an open source filament extruder for less than $250 in components that can take ABS or PLA resin pellets, mix them with colorant, and extrude enough 1.75 mm diameter ± 0.05 mm filament that can be wrapped on a 1 kg spool. The machine must use the Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0) license.

The use of DIY filament extruders like the Lyman can significantly reduce the cost of printing with 3-D printers.^[2] The Lyman filament extruder was designed to handle pellets, but can also be used to make filament from other sources of plastic such as post-consumer waste like other RecycleBots. Producing plastic filament from recycled plastic has a significant positive environmental impact.^[3]