Josef Prusa released his open source Prusa i3 3D printer design as part of the RepRap Project back in 2012. The design was very well received, thanks to its high performance and low cost. Since then, numerous manufacturers have produced direct clones or derivatives of the i3, making it the most popular 3D printer design of all time (according to 3DHubs). Joseph Prusa launched Prusa Research and then started selling the Original Prusa i3 in 2015, which has become one of the respected printers on the market. Now Prusa Research is back with a completely new CoreXY 3D printer called the Prusa XL.
The CoreXY style of 3D printer offers both size and speed, thanks to its innovative looping drive belt system. That dramatically reduces moving weight, which improves print quality — especially when printing at very high speeds. The print bed, which is often the heaviest part of a 3D printer, either doesn't move at all or only moves in the Z axis. X and Y stepper motors are stationary, which eliminates a large portion of the moving weight that a traditional 3D printer must deal with. CoreXY printers can achieve speeds of more than 400mm/s and still produce respectable results.
As the name suggests, the Prusa XL is big. It has a build volume of 36 x 36 x 36 cm (14.17 inches cubed), which makes it one of the largest consumer FFF 3D printers on the market. At that size, an i3-style printer would produce poor quality prints at anything but a very slow speed, but the Prusa XL's CoreXY design lets it print fast while maintaining the kind of print quality users expect from an Original Prusa machine.
The Prusa XL also incorporates a number of innovative features that help compensate for the large size. For instance, the bed has 16 individual heater boards. Small gaps between the boards allow for thermal expansion, which is necessary to avoid bed warping at this size. It is also possible to heat only the portion of the bed you'll be using, reducing energy usage.
To handle high print speeds, the Prusa XL's extruder needs to push a lot of plastic. That's why Prusa Research designed a new "Nextruder" extruder design, with a cycloidal gear box and a massive extruder gear. To detect thermal creep, the hot end contains an additional thermistor near the top. That improves safety and helps to avoid jams caused by heat creep.
The Original Prusa i3 MK3S had automatic bed leveling, but that meant that the printer's Z axis would move slightly during printing to compensate for a warped bed or a bed that wasn't trammed. The Prusa XL has true automatic bed leveling (bed tramming), which tilts the bed as necessary instead of compensating in software.
The electronics were also improved with a new full-color touchscreen interface and a modular wiring system. An RGB LED lighting system adds nice ambiance and could help users create more exciting time lapse videos of their prints. Prusa is even considering releasing an official, though unsupported, Klipper firmware for those users who have grown to love Klipper in other CoreXY printers.
The most exciting feature by far, however, is the new swappable toolhead system. This is similar to the E3D ToolChanger design and lets the printer switch between different extruders during a print, allowing for multicolor or multi-material prints. An innovative calibration routine ensures that quality doesn't suffer after a tool change.
Prusa Research hasn't yet announced an official release date, but you can reserve a pre-order by placing a $200 deposit right now. A semi-assembled Prusa XL with a single toolhead will cost $1,999. A Prusa XL with dual toolheads will cost $2,499 and a Prusa XL with five toolheads will cost $3,499.