Many of you have eagerly awaited an update on the Prusa CORE One and I’m happy to share one right now! We had a pretty busy holiday season: all our testing units were running nonstop. The firmware team is ironing out all the remaining kinks and everything looks good. There’s also a very interesting update to the CORE One’s hardware! But I’m getting ahead of myself. Let’s take it from the start.

Getting review units ready, final units in close pursuit

Right now, we’re going through the last part of internal testing. Even though the CORE One shares many of the proven parts with the MK4S, it’s still a vastly different printer and it takes much more than just remapping the axes in the firmware to make it work.

For the past several weeks, we’ve been preparing new assembly stations, adjusting testing machines, and more. This is all part of an ongoing process. Last year, we heavily focused on boosting our entire manufacturing to avoid delays. I hope it was quite noticeable with the much-improved availability of the MK4S and HT90, and we’re doing our best to continue the trend. As promised, the first units of the Prusa CORE One will be sent to customers by the end of January. When you order the Prusa CORE One assembled now, with the current queue length, we expect to ship it in March.

And if you want a little behind-the-scenes sneak-peak, we have a short video showing the drop tests. These are necessary to ensure that even if your package is handled with little care, the printer inside survives. However, we had to adjust one thing to meet all the requirements: the assembled printer now comes with the LCD Panel unmounted, otherwise the risk of damage would be too high. When you unpack your assembled printer, you simply need to attach the cable to the LCD panel and tighten two screws. Other than that, the printer is truly “plug and print”.

Cable chain? Umbilical? Introducing the SwingArm!

We love to innovate and we constantly improve our existing printers. Even with the tight time constraints in the development of the CORE One, we reworked a vital part of the printer before release. I’m talking about the energy chain – it’s a flexible plastic chain that leads the cables and filament to the extruder. It’s pretty sleek and looks cool, however, it has a major disadvantage: everything is stuffed extremely tight inside it, to the point where it becomes impossible to replace the cables without removing the connectors. This didn’t sit right with us. After all, we want the printer to be extremely easy to assemble, run, and maintain.

So we came up with a different solution. We call it the SwingArm – it’s a short, hinged metal arm that guides the textile-sleeved cable bundle. The arm’s length and movement are carefully optimized to minimize strain on the cables. It’s a rather ingenious solution (pardon the little pat on our back) because it makes mounting or replacing the cables a breeze – you simply remove a couple of velcro fasteners and that’s it. It’s lightweight, space-efficient, and doesn’t cause any additional resistance. And we’re able to manufacture it locally! 🙂

This is all part of the CORE One’s philosophy. We want it to be the best investment in 3D printing: you’ll get outstanding print quality, reliability, easy maintenance, high speed, and all the bells and whistles you would expect from a Prusa printer. And when there’s better hardware available, you have the option to simply replace what’s necessary and continue printing. It’s like when you buy a proper gaming PC – you don’t have to replace the whole machine every time a new GPU comes out.

Update on Accessories

Chamber Camera: The camera will start shipping in late February. If you already ordered the Prusa CORE One, you can edit your order and add the camera, however, please note that the order will be shipped only when the camera becomes available – i.e., late February. If you want to receive your CORE One faster, please make a separate order for the camera.

Advanced Filtration: It’s based on the XL’s Advanced Filtration solution (includes a HEPA filter, carbon filter, and a high-pressure blower), it connects to the rear side of the printer, and we’re aiming for late February / early March. Just like with the camera, you have the option to add it to your existing CORE One order, however, it will push back the shipping date of your printer until the Advanced Filtration is also ready for shipping.

MMU3 for the CORE One: development & testing are underway, and we’re making the final changes. The MMU3 unit is mounted on top of the frame, and the set includes a custom top cover for the CORE One. Then, the final testing will commence before we’re ready to wrap everything up and start shipping. Our current estimation is April 2025. We really pushed the reliability of the MMU3 as far as we could and there are plenty of examples with huge, complicated prints that were finished flawlessly, with zero interventions and zero tinkering. Plus, don’t forget that the MMU3 is the most material-efficient single-extruder solution out there!

*Please note that this is a photo of a pre-production prototype, the top cover will be transparent (same material as the door/side windows) and may have slightly different shape

There are many ways to make the MMU3 work with the CORE One. The setup portraid above, the one we’ll be offering, is very close to how MMU3 works with the MK4S, down to details such as the length of the PTFE to the print head. This setup is reliable, efficient, it doesn’t require many new expensive parts, and we know what to expect from it. With that said, we are exploring different ways to integrate the MMU3 with the CORE One, especially focusing on the form factor—a common request we’ve heard from the community. These alternative setups could include mounting the spools above, below, or even on the side. But these solutions are likely to be more expensive, and each comes with its own set of trade-offs. We’re still in the process of evaluating them, so I don’t want to make any promises about timelines or even confirm that we’ll definitely offer one of these alternatives.

With all of that said, here’s a sneak peek at one of the early prototypes we’ve been working on. The whole spool holder and MMU3 unit can slide out for easy maintenance, and we’ve integrated the buffer right below the spools. It’s still a crude prototype, but I thought it was too cool not to share! 🙂

This is NOT A PROTOTYPE OF AN UPCOMING PRODUCT, it’s slapped together with hot glue and just an exploration of one of the possible development paths

We are working on an injection-molded Drybox that fits neatly on the spoolholder. Those of you who visited our booth at Formnext may have seen a prototype. Once we’re done with adjustments and testing, we should be ready to release it in April-May.

And this is far from everything! Our community has been incredibly active even before the printer’s launch. We have published STEP files of both side panels so that designers could already start with various ideas and the results are pretty awesome. We especially like the SKADIS Mod by ScottWolfs!

Update on Shipping Dates

So, a quick recap: the assembled version of the Prusa CORE One will start shipping by the end of January (next week). In the announcement article, we gave an estimation on the availability of the Assembly Kit and the Conversion Kit and I’m happy to say that we are on the right track to meet the projected timeframe, with only a small difference – we will swap the order of kit releases.

The Prusa CORE One Assembly Kit is now scheduled for March 2025 and the Conversion Kit (MK4S->CORE One) will follow in April. If you still have the original MK4 3D printer, we will also offer a bundle that will contain both the MK4S upgrade and the CORE One Conversion Kit – it’s necessary to have the “S” upgrade parts as they are used during the assembly of the CORE One.

We’re planning to enable orders of both the Assembly Kit and Conversion Kit once the assembled version starts shipping, and we will announce it 24 hours before it happens on our social media channels. If you want to receive the notification, you can already set up a watchdog in our store, so you’ll be notified as soon as the orders go live!

So, this is it – at least for now. We’ll keep you updated on the progress and availability of accessories.

Happy printing!