The New Original Prusa MINI Introduces a Radical New Design at a Great Price

When Josef Průša first released his Prusa i3 3D printer design back in 2012 as part of the open source RepRap Project, the hobbyist 3D printer market was full of underperforming and unreliable models. But the Prusa i3 quickly gained a reputation as a solid and affordable option. It wasn’t long before the design was being reproduced by manufacturers all around the world. Since then it has become one of the most popular designs in history, and Josef Průša has continued to improve upon it under the Original Prusa brand name. Now Original Prusa is back with the completely-new and radical Prusa MINI, which packs many features into an affordable package.

If you’ve ever owned a 3D printer yourself, there is a very good chance that it was based on the Prusa i3 design. It has been the basis for many popular models over the years, and though those often took on a life of their own, the layout is very recognizable. The Original Prusa MINI, on the other hand, doesn’t resemble the Prusa i3 in any way. It’s a completely new design that shares many of the features present on the newest Original Prusa i3 MK3S, but with a layout all its own.

The most obvious difference between the Original Prusa i3 MK3S and the new Original Prusa MINI is the cantilevered X-axis design. That has just one Z-axis lead screw, instead of two—though there are dual linear rails. Lead screws and stepper motors are some of the most expensive parts of a 3D printer, so this change dramatically lowers the cost of the new Original Prusa MINI. It also helps keep the new design as compact as possible. Despite that, it has a build volume of 7”x7”x7”—just barely smaller than the 9.84”x8.3”x8.3” build volume of the Original Prusa i3 MK3S.

Many of the other specifications are also quite similar between the two models. They have an identical 0.05 – 0.35 mm layer height, 200+ mm/s maximum travel speed, and included 0.4mm nozzle. The MINI is also getting the fantastic magnetic sprint steel built plate that has been such a hit on the i3 MK3S. Maximum temperatures are slightly lower on the Original Prusa MINI, at 280°C and 100°C for the MINI compared to 300°C and 120°C for the i3 MK3S. That won’t be much of an issue for most users, as those temperatures are more than adequate for the vast majority of filament types on the market.

The most surprising part of this announcement is that the MINI is getting a number of features that the more expensive i3 MK3S doesn’t even have. Those include a 2.8” color LCD screen, a Bowden extrusion system, a custom 32-bit control board, built-in WiFi and Ethernet connections, and support for loading print files and firmware from USB drives. That new STM32-based control board has upgraded Trinamic 2209 silent stepper drivers, which should perform at least as well as the Trinamic 2130 drivers found on the i3 MK3S’s Einsy RAMBo control board.

How much do you have to pay for all of that new tech on the Original Prusa MINI? Just $349—less than half of the $749 price for the kit version of the Original Prusa i3 MK3S. Importantly, the MINI will only require minimal assembly. The printer will ship almost fully-assembled, and you’ll only have to connect the three main sub-assemblies together. That’s a huge advantage, as the Original Prusa i3 MK3S generally takes several hours to assemble.

As Josef Průša himself pointed out in the Original Prusa MINI’s press release, the economics of the new model are quite appealing for people interested in building a 3D printer farm. You can purchase two of the new MINI 3D printers for less than the price of one i3 MK3S. Running those two simultaneously will let you print more parts in much less time than you could with just one 3D printer.

As far as potential downsides, we can only think of two. The first is that the cantilevered design may not perform as well as the dual Z-axis, because of a lack of rigidity. We won’t know for sure until we get our hands on one to test. The other is that the Original Prusa MINI is not compatible with the MMU2 (Multi-Material Upgrade V2)—an add-on that allows users to print a single part with up to five different filament types.

Those are, however, very minor caveats. From what we can tell, the Original Prusa MINI seems to be an incredible value from one of the most well-respected names in the 3D printing business. That’s especially true when you consider how many new features are being introduced. If the Original Prusa MINI lives up to even a fraction of the hype, then it will make most other budget 3D printers obsolete.