Most hobby 3D printers are based on FDM, extruding a single-color noodle of melted plastic to build up an object. Powder-based inkjet 3D printing allows you to print detailed, full-color models from a plaster-like material. The process uses ink and water droplets, dispensed from an inkjet print head to selectively fuse and color layers of a powdered binder material. When you see an offer for a 3D printed miniature version of yourself (or someone else), they are made with powder. [Aad van der Geest] wants to put this technology on your desktop with ColorPod, a kit that converts your FDM printer into a powder printer.
On the hardware side, his solution consists of a special printhead — shown in the header image — that mounts next to the extruder nozzle of an FDM machine. The printhead features a powder dispensing mechanism and two off-the-shelf HP inkjet cartridges. One of them contains water, the other one can be used to color the print. The powder dispenser employs a pager motor to sprinkle down fine layers of PVA powder while a spinning roller to evens them out.
Unlike industrial machines (and the one [Aad] built in 1998), which print objects in an enclosed, piston-like build volume, [Aad’s] addon simply prints the object within the heap of powder it lays down on the build plate. [Aad] provides PC software that processes 3D models from the STL and OBJ format into printable G-code and streams the instructions to both the printer and the addon. It also generates support walls around the model to stabilize the powder heap.
With the hardware working, [Aad] now sells his add-on kit for $488 ($349 for the PCB and $139 for the rest of the kit). Looking at the commercially available powder bed alternatives, [Aad’s] desktop-capable solution is underbidding the competition by about $50k. It’s certainly not a mature product and PVA dust and explorative goodwill pave the way to success, but [Aad’s] results speak for themselves. He made it work, and he’s providing us with tools to do the same. Check out the video below where [Aad] demonstrates the working kit on an Ultimaker 2.