Prusa Research has announced that it will begin shipping units of its Original Prusa MMU3 for MK3S+ machines. Those for Original Prusa MK4 3D printers will follow in the coming weeks.
The MMU3 is the third iteration of Prusa’s take on the multi-material unit. The add-on enables users to print with up to five filaments at once and features “dozens of major changes” from its predecessors. In usual Prusa fashion, the release notes are expansive, but we’ve done our best to highlight the meaty bits.
New and most prominent with the MMU3 is a cassette-style buffer that prevents the filaments from tangling. Users feed the filament tubes into the cassettes, then insert them into the buffer in what appears to be a simple, painless, plug-and-play process.
Because the unit uses only one nozzle, it still requires purging between each material. The post takes a cute dig at other single-nozzle systems that eject additional purge material (*cough* Bambu Lab *cough*). It explains that Prusa’s long-implemented “smart compact semi-hollow wipe tower” remains. Additionally, there are a couple of new PrusaSlicer features – “wipe to object” and “wipe to infill” – adding to this, giving users the option to purge excess material into objects themselves or an object’s infill, helping save material.
Several quality-of-life improvements, many of which are based on community feedback for the temperamental MMU2, also arrive with the MMU3. Prusa has reworked all the unit’s plastic parts, for example, and added new metal parts in an effort to improve robustness. There’s also a redesigned material selector with a magnet-assisted sensor, which Prusa says is more reliable, a new maintenance position for easy access to the MMU3’s internals, and an improved IR filament calibration system.
Completely rewritten firmware, meanwhile, takes strides toward making the MMU3 more user-friendly than the MMU2S (which we’ve previously described as “somewhat finicky at best”). The new firmware, which is also compatible with the MMU2S, “allows for full two-way communication with the printer”, providing users with sensor status, error messages, and other printing-related options. Prusa says this also results in its machines attempting to automatically solve problems without user input.
The Original Prusa MMU3 is priced at $299 on Prusa’s store, which lists a four-to-five-week lead time for new orders. It ships as a DIY kit that requires users to print plastic parts themselves. Should you want those plastic parts pre-printed, you’ll have to fork over an additional $30. As mentioned above, units for MK4 printers are slated to head buyers’ ways relatively shortly, with Prusa eyeing a late August or early September ship date.
Prusa also says an MMU2S-to-MMU3 upgrade kit for MK3S+ printers is coming soon, as well as an article on how to adapt the MMU3 to other Prusa machines, so keep an eye out in that regard. And, of course, for the full deep-dive into the MMU3, check out Prusa’s blog post on its release.
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License: The text of "Prusa Starts MMU3 Shipments, MK4 Users Will Have to Wait" by All3DP is licensed under a Creative Commons Attribution 4.0 International License.