5/10/23
What is high-speed printing? and how do we define it? When creating PolySonic™ we looked at three crucial aspects that can classify a material, as high speed. But this is only half of the story, because High-speed printing is a marriage between material and machine, and like in all good relationships, both parties need to work together for positive results.
Firstly, we look at the extrusion, to print fast, you must be able to extrude fast and at Polymaker, this is one of the first problems to solve. By increasing the flowability and fine-tuning the molecular weight, we can decrease the viscosity of the molten plastic to ultimately achieve a higher print speed. As volumetric flow increases, the time that the filament spends inside the hotend decreases, leaving less time for the heat to transfer from the nozzle to the filament.
To scientifically measure this, we built a custom rig, called the ECP. With a high-precision encoder wheel to measure the exact length of filament feeding in through an E3D Hemera. Then just below, a volcano hotend is mounted on two load cells to accurately measure the extrusion force. With this equipment we can plot out a graph, showing us the extrusion curve for a given temperature and flow rate. This lets us measure the printing window of a material by incrementally increasing the extrusion speed until failure.
If we look at this graph from the ECP showing our regular PolyLite™ PLA extruding at 230° degrees, there’s an inflection point where the extrusion force rises exponentially. This is caused when the filament doesn’t fully reach its molten state inside the nozzle and the shearing forces start fighting back against the Hemera. The result of this is under extrusion, poor surface quality, weak layer adhesion and eventually a failed print. This is usually noticed on the layer starts, infill, overhangs, and ruptured top surfaces.
Thanks to PolySonic™’s optimised extrusion efficiency you can ride the volumetric wave 40% further than with regular PLA, allowing you to confidently build high-speed profiles and produce more parts in less time, with the same accuracy. But there’s a limit in the pursuit of volumetric flow, as the less viscous the plastic is, the more difficult it becomes to form when 3D printing with high accelerations.
This leads us nicely to our second aspect, which is the forming of the material. If we wanted to produce a filament with the highest melt index then we would just extrude a wax filament, but it’s what happens after plastic leaves the nozzle that defines how useful a high-speed material is. The ability of the material to rapidly cool after extrusion is what allows a high-speed material to print fast without any loss of quality. With optimized rheology, PolySonic™ can switch from fluid to solid with minimal shrinkage, producing crisp corners, fine details and smooth surfaces with no shark skin effect. As the new generation of high-speed printers are equipped with auxiliary cooling, PolySonic™ is perfectly adapted to lightning printing speeds with rapid cooling characteristics.
PolySonic™ PLA – the first in the family of high-speed 3D printing filaments, comfortably build printing profiles over 300mm/s with superior print characteristics. Initially available in 5 colours.
PolySonic™ PLA PRO – An improved toughness PLA compounded with impact modifiers that produce ductility similar to ABS and stiffness outperforming ASA & PETG. Initially available in 2 colours.
This leads us to our third and final factor, the mechanical properties of the 3D printed part. It’s all good and well printing at ludicrous speeds, but are these parts functional? If your parts have no strength, then we believe the speed advantage is futile.
Proper layer adhesion paired with tensile strength and impact resistance is the final ingredient in the recipe for PolySonic materials. In a mechanical strength test with samples printed at high speeds and classic speeds, PolySonic PLA only shows a 6% drop in properties. When we compare this to regular PLA, the advantages become clear, in bending strength, impact resistance and tensile strength, PolySonic allows you to print fast and functional.
When we find a balance between all three factors, you can truly unlock the potential of high-speed printing. By saving time and producing more parts with your printer, PolySonic™ allows you to bring your ideas to life, faster than ever.
Article from our partner Polymaker
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