Multi-Color Printers and Extruders

constructinnovator Printer Parts 09/03/2016 | 0

Multicolor 3D printing possible from a single nozzle

The most common type of home 3D printer is the Fused Deposition Modeler, (FDM) type of printer, which works by melting a plastic filament with a heater element (hotend) and extruding the melted plastic out of a small nozzle (like icing a cake). Current hotends can only handle one filament at a time, so the 3D printers that can handle multiple colors require a different hotend for each one.

This causes a number of problems: the nozzles must be exactly the same height from the work surface, or they will damage each other’s work; the distance between the nozzles must be carefully calibrated and the printer’s software must make corrections to keep the output in the same place.

The Diamond Hotend developed by 3D printing specialist RepRap.me addresses many of these problems by combining three heating chambers with a single nozzle to create a new sort of 3D hot end that can extrude different colors.

The concept is simple. The heating element has 3 chambers that all meet at a central nozzle. The actual mixing area where all three meet is actually quite small. The resulting nozzle is shaped like a diamond, which explains the name.

The resulting extruder has several advantages over multiple-extruder systems. The single nozzle eliminates the calibration problems associated with having separate nozzles for each color, and the single output orifice alleviates the problem of out-of-level nozzles hitting the working surface being created.