The MK4S is now available as "Plug and Print" assembled printer (take it out of the packaging, let it perform the 10-minute self-test and start printing) and Printer kit available. It is also available in a fully assembled package, with the ready-to-use MMU3 unit on top, so you can start printing with multiple colors immediately after unpacking.
And of course there are also an upgrade kit for all previous owners – our iconic printer design This is where it really comes into play: If you already own an MK4, you don't need to buy a completely new printer. You can simply use it for 99 USD / 109 EUR (incl. VAT) Upgrade and get ALL the new features of the new model – and they're pretty awesome! I'll give you a full overview in a second, but first, let me briefly summarize the MK4, just in case this is the first time you've heard of it.
The MK4 quickly became our best-selling 3D printer and has so far over 4,000,000 hours of testing collected in our printing farm, which makes the MK4 extremely reliable (the warranty claim rate is consistently below 1%).
Our printers are getting better and better. Following the launch of the MK4, we introduced free updates, such as a completely revamped network functionality with instant network printing, G-code streaming, and the compressed .bgcode file format for faster network transfers, a significantly improved Prusa Connect, and numerous firmware enhancements (like the cold pull assistant). And there are even updates for the MK3. for over six years Updates.
We ship approximately 10,000 3D printers every month directly from our headquarters in Prague, Czech Republic, and have also started production in the USA. There are over half a million Original Prusa printers in use. only about 20 printers per month They must be returned to us for practical maintenance. Don't believe it? Take a look at our Trustpilot review or Google reviews! 😉
So, and now for the new things!
Short and sweet!
Compared to last year's model, the MK4S has a Completely redesigned cooling system that enables significantly faster printing while maintaining consistently high print quality (durability, smooth surfaces) and dimensional accuracy.
But we have improved the quality even further in several areas. The new high-performance 360° cooling system enables the printing of extremely steep overhangs. In areas where other printers would require a considerable amount of supports, the MK4S can effortlessly print a great-looking overhang. Why is this important? Because with fewer supports, you save both time (faster prints) and material (less plastic waste). And it's an absolute boon if you plan to print with flexible filaments, where removing supports can be quite tedious. Plus, you get an even improved surface quality especially with materials like PETG.
Furthermore, the MK4S now comes standard with a high-flow nozzle Equipped with nozzles we developed ourselves based on CHT technology. In short: High-flow nozzles allow you to print faster with the materials you already have, know, and love. You don't need to search for new "high-speed" filament. Depending on the material, you'll get a 45% to 114% higher flow rate.
Furthermore, we have further optimized our firmware and print profiles, so that all these things work together make the MK4S faster than the MK4 and deliver even better print quality at the same time. And since we use the MK4 as its base platform, the MK4S inherits its proven reliability and other advantages, such as the open design, the effortless maintenance and upgrades made possible.
We have a brand new native iOS and Android Prusa app For remote print monitoring and management, allowing you to print projects directly from printables without using a slicer. The app is already available in the respective app stores and offers another useful feature: you can easily set up the printer's Wi-Fi with an NFC tap.
Many of the MK4S parts are now made from PC Blend Carbon Fiber or manufactured using injection molding And we're also introducing two fantastic new additions for all modders and hackers: an optional GPIO "hackerboard" and an accelerometer add-on For printer modders.
This is a brief summary of the new additions and innovations. I'm sure you have many questions about your orders and upgrades, so you'll find the most important summary in the box below:
Shipping information, upgrades, information for existing users
Here is a brief summary of the most important things about the MK4S, its availability, and information for existing MK series users:
- Anyone who ordered an MK4 (assembled or as a kit) between August 1st and 12th will receive one Voucher for a free MK4S upgrade – You only need to cover the shipping costs (the vouchers will be sent by August 16th and you will receive priority processing of your order)
- The MK4S Assembled 3D printer, MK4S Printer Kit, and a new bundle with the MK4S Assembled and MMU3 are now available in our e-shop, and we have units in stock.
- MK4S Upgrade Kits (for upgrading an older printer) will be available from the end of August.
- All currently undelivered orders the MK4 3D printer and MK3.5/MK3.9 and MK4 upgrades will be automatically converted into the "S" upgrades
- Owner discounts that apply to MK4 printers will automatically be applied to the MK4S version as well.
These are some truly significant additions, definitely not just a minor reliability upgrade. If you want to know more, read on. Now let's get down to the technical details! 😉
Redesigned 360° cooling
We spent a long time searching for a new fan to replace the current one. That was quite a challenge, because... The MK4's cooling was already very good , and there was a long list of requirements to meet (weight, pressure, noise, PWM, and more) if we wanted a brand-new print fan. Remember when we said that the innovations from the Prusa Pro series would trickle down to our desktop printers? We weren't kidding 🙂 We really learned a lot when we developed the industrial Prusa Pro HT90 developed, and now we can fully utilize our knowledge in the MK4S.
The new printer features a completely redesigned 360° cooling solution. It utilizes a high-pressure turbine with a redesigned fan cover that provides powerful cooling with carefully optimized airflow.
We considered and tested many other solutions, such as a side-mounted fan. But A side-mounted fan does not provide complete coverage from all sides. (The object itself can block the airflow). However, with a powerful fan mounted on the extruder, we can direct the cooling precisely where we need it.
The new fan may look bulkier than the old one, but the Nextruder's weight remains virtually unchanged. The fan model and its position were carefully selected after months of research, including virtual airflow simulations. Its position is precisely calculated to ensure it doesn't cool the nozzle or blow hot air back towards the heatsink. As always. We went a little beyond what was necessary. – the new turbine is powerful enough to run at 60-70% of its maximum speed most of the time (it only goes up to 100% in certain situations), so that they are still very quiet and at the same time delivers much higher performance compared to the old model.
The new cooling design enables effortless printing of extremely steep overhangs (Depending on the model geometry, you can easily print at angles of up to 75 degrees), allowing you to print even very complex models without supports, saving both time and material. Another improvement is thanks to the new cooling system: whenever you've printed a tall, thin object (a tower, a spear in the hand of a miniature warrior), you may have encountered a minor issue: if the nozzle remained in one spot for too long, it tended to melt some of the already applied material. With a more powerful cooling system, the quality of such parts is significantly improved.
New high-flow nozzle
The MK4S features a new, custom-designed high-flow nozzle based on CHT technology. Depending on the material, you can achieve a Increase in volume flow between 45 and 114 percent.
As I mentioned before, a high-flow nozzle essentially allows you to print faster because the material in the nozzle melts faster (and more efficiently), resulting in an improved volumetric flow rate. If you want to print quickly, it's not just about speeding up the extruder; you also need to get the filament to its optimal melting point. Otherwise, while the print might finish quickly, the adhesion between layers will be extremely poor.
With the new high-flow nozzle you can Get more out of the same filaments you already know and love You don't need to switch to special filaments just to achieve a higher speed. Take a look at the table below – it gives you a good overview of the differences between the various nozzle models. Everything is measured with standard materials; you don't need to pay attention to the fine print that says "measured with high-flow filament" 😉
| Comparison of volume flow – 0.4 mm and 0.6 mm nozzle | |||
|---|---|---|---|
| Standard nozzle [mm3] | MK4S High-Flow Nozzle [mm3] | increase | |
Replacing the nozzles is still extremely easy. Simply loosen two knurled screws (no tools required) and detach the entire hotend assembly, or use a 3D-printed nozzle adapter and replace just the nozzle (it takes about 30 seconds). We also offer an adapter that makes the Nextruder compatible with any type of V6 nozzle.
Let's talk about speed!
The combination of optimized firmware, print profiles, and the new high-flow nozzle enables the MK4S to print faster than its predecessors. This is thanks to the native implementation of Input Shaper and Pressure Advance technologies. It is one of the fastest printers on the market .
We're not big fans of the speed boat race benchmark, but you'd ask anyway 🙂 The Benchy can be completed in just 14 minutes according to the rules. (And it looks fantastic). And our specially designed "bonkers" Benchy It can be done in just 8 minutes .
But just to be clear: Speed is nothing without quality. So, if you ever need to reprint something because the print failed or the durability doesn't meet your expectations, a printer that's faster on paper isn't necessarily faster in reality. With our printers, we always strive for maximum print quality, even if it means sacrificing a little printing time. A few extra minutes of waiting for a better-looking print is worth it. And if you're in a hurry, We have two new rapid prototyping profiles. for maximum speed.
Prusa App – Simple and clear user interface, focus on functionality
With the release of the MK4S, we are also introducing our new (and fully optional) native Android and iOS app Yes. And don't worry: it's not just for the MK4S – any Prusa Connect-compatible printer will work too. And yes, I know what you're thinking: everyone has an app now. That's certainly true. But sometimes it goes too far, and many devices can't even be properly configured without an app! And what do you do if the app isn't compatible with your phone? That infuriates me, and I think it goes without saying that this isn't what we're aiming for.
The Prusa app has a beautiful, clean, and simple design. You can get a quick overview of all your printers, see all running jobs, and start, pause, and stop prints from anywhere. You can also receive push notifications. All in all, it's a good package of useful features for remotely managing your print jobs. But there's one more feature that I think many of you will find very useful: you can access printables directly from the app. If a project contains a printable file, you can simply tap the "Print" button and start printing immediately. without needing to use a slicer.
With the app you can also Simply set up Wi-Fi by tapping the NFC tab on the electronics cover.
And as with everything we do at Prusa Connect We will continue to add useful new features over time.
We plan to add the following things in the near future:
- Camera support
- Advanced notification settings
- Improved management of direct printing of printables
- Widgets
- …and more
However, rest assured that The app will remain optional . So if you prefer simplicity to smart features, the MK4S works just as well offline as all its predecessors.
Safety always comes first. You can operate your printer in offline or local mode, and we will never secretly collect information about your printed files or your printer's environment unless you explicitly agree to share it with us (e.g., for technical support).
Our printers can It can be operated completely offline , the Wi-Fi module is removable, and the Firmware files and PrusaSlicer They are open source, so you can view the code at any time and conduct an independent review. We also have a page with a a clear overview of our open-source efforts Released. You can easily update the printer's firmware via a USB stick, and there's something else that's often overlooked: We even allow offline updates of PrusaSlicer profiles, so you don't need internet access to use PrusaSlicer to its full potential!
And as a company based in the EU, we are obliged to comply with the strict GDPR regulations.
Accessories for Makers
With open-source firmware, printable plastic parts and more, our printers are very open to any kind of user modifications, optimizations and hacks. And we want to go one step further. That's why we're now introducing an optional accessory: a GPIO “hackerboard” for advanced users. This small electronics board connects directly to the main board and can be controlled with G-code commands. For example, you can solder on an LED strip and have it blink in specific colors when a print is finished. You can also set up a remote camera trigger, enable filtering, or design your own print harvester. The possibilities are practically endless, and we're excited to see what crazy ideas you come up with!
The GPIO hackerboard is currently as Pre-order available And we'll be shipping it in a few weeks – we're currently finishing the documentation, so you can come up with some cool projects in the meantime 🙂
The other accessory is a Optional accelerometer for printer modders . Our printers come pre-configured with optimized Input Shaper values. However, if you decide to make significant modifications to your printer (e.g., by installing a mod on the Nextruder), you may need to recalibrate these values. For such occasions, we are releasing an optional accelerometer accessory that allows you to calibrate your printer. Of course, the difference on a stock MK4S is negligible. The accelerometer is Now available in our shop .
Improved print quality
Every manufacturer claims that their printer delivers the highest quality prints – but what does that actually mean? When we say we strive for the highest print quality, we mean the following areas:
- Dimensional accuracy
- Unrivaled overhang quality
- Solid, durable prints at high speed
- Beautifully smooth surfaces
- Colorfastness
Most of these points are fairly self-explanatory, so I'd like to focus on two of them, as we've made some significant improvements here. I've already discussed the considerably improved printing of overhangs. So let's take a look at the dimensional accuracy and durability of the print.
Dimensional accuracy
Regarding dimensional accuracy, I feel it's not discussed enough. At least not online, because at various events and trade fairs, people often tell us that they print fast prototypes on other printers, But if they want precision and repeatability, they always end up with our machines.
If you are designing a part that is meant to fit an existing object, or if you want to ensure that the holes for screws line up perfectly, you will want a precision 3D printing We have it. Our firmware and print profiles are optimized for maximum print quality, and we have the proof 🙂 We compared printed models from various machines with the original 3D model. And we used different techniques to compare them. Below you can see a measurement taken with the Zeiss Metrotom 1500, a state-of-the-art industrial CT scanner.
On the left you see a standard MK4S 3D print, on the right a print from a competing printer. The more the color deviates from green (either towards red or blue/violet), The less precise the pressure, the less accurate the measurement . The measurement was carried out by the Institute of Machining Technology, Design and Metrology, Faculty of Mechanical Engineering, CTU in Prague. The fixtures were compared with the STL model using the Carl Zeiss Metrotom 1500 computed tomography scanner.
Another test was carried out using a high-precision multi-sensor measuring system, the Keyence LM-X-100TL, to see how well the dimensions matched.
We chose this option because standard tolerance tests for the entire print don't truly reflect reality. When the entire model is 3D printed, tolerances can indeed allow for movement within a controlled tolerance test. However, when you need to incorporate other components (screws, nuts) with precise dimensions, reality can be quite different.
We hear from many of our users at various trade fairs and events that after experimenting with other devices, they return to our printers precisely because of the precision we achieve.
Stable, long-lasting prints
The combination of the 360° cooling system and the new high-flow nozzle enables the MK4S to To deliver very durable, robust prints . It's not just about the overall cooling performance, but also about the most effective airflow. Extremely powerful fans tend to create an overcooling effect, resulting in poor layer adhesion. Most of the time, the MK4S print fan doesn't even come close to running at its maximum speed, but it's the air distribution that makes a huge difference (which is also why we don't use a fan covering the entire print area).
The high-flow nozzle ensures that The filament needs to be melted properly so that it adheres optimally. We've also adjusted the print profiles. The SPEED profiles are now optimized for faster prototyping, but we've intentionally kept the STRUCTURAL profiles at the same speed to further increase print durability. Yes, our profiles might be a bit conservative when it comes to speed, but you can be sure that any kind of fixture you design for your workshop won't fall apart after a while.
Available as a kit and fully assembled
The MK4S is as fully assembled A "Plug and Print" version is available, where you simply take the printer out of the packaging, place the filament on a spool holder and complete the automatic self-test. All of this takes less than 15 minutes. – and you're ready to print. We have Manuals, tutorials, guides, tips, tricks, and much more to get you started with 3D printing in no time. Plus, there's a great community and our renowned 24/7 tech support , available via live chat should you require assistance.
The design of our printers also allows us to... kit We offer one of the best STEM projects available. You can assemble the entire printer yourself, or with your children, grandparents… anyone! All you need is a set of screwdrivers and some time, and you can build your own MK4S while learning all about 3D printers and how they work. That's a lot of fun! and the kit is still one of our most popular offers.
Greenguard certification for the MK4
Before I conclude, I'd like to mention something that has generated a lot of discussion online: safety regarding fumes from open-frame printers. In short: The Original Prusa MK4, using Prusament PLA and Prusament PETG, has passed the UL 2904 test and received the prestigious Greenguard certification, the first and only desktop 3D printer on the market to do so. And the MK4S will follow shortly.
PSA2🚨 Today is a great day to talk about 3D printing safety 🤓 Another elephant in the room is “fumes” from open-frame printers. TLDR: It can be safe and I have the receipts ⤵️
The “fumes” are basically two things – particles and chemical emissions. They are affected by two... pic.twitter.com/udulYQyh1S
— Josef Prusa (@josefprusa) August 4, 2024
To explain: The "fumes" are essentially two things – particles and chemical emissions. And their nature depends on the composition of the filament and the printer itself. In other words, even if you label a material as PLA, it can contain completely different components than PLA from another brand. For this reason, we tested a specific combination of 3D printer and material.
With printers, it's primarily about temperature and the time used to heat the filament. Overheating the material to increase flow rate can lead to a less safe printing environment. The CHT nozzles seem to work better – increased flow rate without overheating. Either way, the only way to be absolutely sure is to run tests. That's exactly what we did, and we passed the standard method for testing and compiling particle and chemical emissions from 3D printers with flying colors. You can view this anytime on the UL website Check.
Available now!
With the MK4S, we're building on our proven, iconic printer design. Over the past 14 months, we've implemented a host of improvements. Setting up everything related to the printer via the touchscreen is easier than ever – including wireless setup. Now you can have the printer search for Wi-Fi networks and enter the password using an on-screen keyboard. There's a new cold pull assistant built right into the printer. Stuck filament detection, user interface configuration, Prusa Connect integration… too many to list!
Furthermore, you can rely on the features that have earned our printers much praise: our excellent 24/7 technical support in 7 languages, incredible reliability, easy maintenance, no glued parts, upgradeability, regular firmware updates, long-term support, third-party support (filaments, mods), plenty of accessories, and much more.
Speaking of accessories: for advanced materials, we have the Original Prusa Enclosure And if you want to print with up to five colors simultaneously, we have the MMU3 – the fastest and most efficient single-nozzle multi-material solution with minimal waste. You don't even need to assemble it, as it comes ready to print with the assembled MK4S.
The MK4S is now available as Fully assembled printer (even bundled with a fully assembled MMU3) and as Printer kit available. The upgrade kits (such as the MK4->MK4S ) will follow in the coming weeks.
Have fun printing!