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Aug 29, 2023

A 3D Printer Designed Specifically for Printing PEEK

The vast majority of hobbyists print mostly with PLA, ABS, or PETG filament. Those are well-understood and documented, and they tend to print predictably in most printers — even inexpensive

The vast majority of hobbyists print mostly with PLA, ABS, or PETG filament. Those are well-understood and documented, and they tend to print predictably in most printers — even inexpensive entry-level models. But in the world of engineering plastics, those materials are all pedestrian. They have decent properties, but don't excel in any area. There are materials that offer better strength properties, chemical resistance, heat tolerance, and more. PEEK (PolyEtherEtherKetone) is one example that has outstanding strength, dimensional stability, and chemical resistance. To help people print this miracle material, nd-3d developed the OP PEEK printer.

PEEK has amazing physical properties, but it is very difficult to print — your printer almost certainly can't print acceptable PEEK parts. That's because PEEK needs a lot of heat. It requires a high-temperature hot end (upwards of 300°C), a heated chamber, and ideally direct part heating. Many printers can reach the proper hot end temperature, but few have a true heated chamber and almost none have the ability to directly heat parts. That direct heating is crucial for properly crystallizing the PEEK material structure and achieving the necessary inter-layer adhesion. To facilitate that, nd-3d had to design a proportional PWM SSR.

A solid-state relay (SSR) works just like a conventional relay, but without any moving parts. It is a bit like a MOSFET on steroids, as it can handle high current. But a normal SSR isn't meant to switch at high frequencies, which is necessary for the kind of PWM (pulse-width modulation) control you would want for this printer's halogen lamp that it uses to heat the part. This custom proportional PWM SSR can accept PWM control from a standard microcontroller and can output 220V or 115V AC power at 10A.

The rest of the printer is fairly conventional. It has a CoreXY kinematic system with most of the parts outside of the chamber to prevent thermal warping. The heated bed can reach 300°C and the hot end can reach 450°. Both the chamber temperature and part heating can be set by layer to allow for maximum flexibility.

In the demonstration videos, it appears that this printer is capable of handling PEEK very well. If you want the OP printer, it looks like nd-3d will be selling fully assembled units — though it is out of stock at the moment. It isn't clear if this is an open source project or if the design files will be made available to the public, but they aren't right now.