When the Original Prusa i3 MK2 was released in 2016, it didn’t take long before it became an instant hit among the 3D printing crowd. It was miles ahead of the competition at the time. A year later, Josef Prusa, the person behind the Prusa i3 series, released an upgrade for the instant-hit 3D printer: the MK2S.

On the surface level, the MK2S appears identical to the MK2, and the familiar orange-and-black color scheme has a lot to do with that. But upon closer inspection, it’s clear that the upgraded model has addressed many of the issues present in the original model. It’s not just a small update with minor tweaks here and there.

As usual, the best way to get the MK2S is through the official Prusa Research store. It’s sometimes available at a few online stores, sold by third-party sellers, and on eBay as a second-hand product, but there are no guarantees if you go down the unofficial route.

Even though the newest entry in the Prusa i3 series – the MK3 – is now out, there are a number of reasons the MK2S is still worth your money. For one, the MK2S is more affordable – the DIY kit now retails for just $599, placing it in the same price range as the Creality CR-10S, while the pre-assembled MK2S goes for $899. In addition, the MK2S also ships faster. Since Prusa Research ships the MK3 in batches, it can take months before you can get your hands on the more recent model.

And that’s not all. Because the MK2 series has been around for two years now, there are lots of people who already own the product. It’s easy to find solutions to the most common problems that you may encounter down the line, as well as get advice on how to get the most out of the MK2S. The MK3, on the other hand, is still a relatively new product – it launched in late 2017 – so the community is still working out the ins and outs.

It’s unfair to review the MK2S relative to the MK3. Simply put, the newer model is a beast and makes other 3D printers under $1,000 hilariously outdated, not counting the MK2S, which is still better than, like, 90 percent of the products on the market. So, to be fair, this review judges the MK2S for what it is, with no comparisons to the features and technical specifications of the MK3.

The Design

The MK2S is an open-framed 3D printer with an aluminum frame. As mentioned, it has that familiar design that makes it hard to distinguish from the MK2. It has an onboard LCD interface with an SD card controller at the base and a spool holder at the top of the frame. It has a single extruder with an E3D V6 hotend, a heated print bed, and a couple of thermistors.

In addition to the cable management, the bearings and the rods have been improved as well, and the electronics are no longer exposed. Unlike most Chinese companies, Prusa Research does not take shortcuts in the construction. The MK2S is durable and stable, with the 3D-printed parts being of higher quality than the ones seen on the MK2.

The print head is well constructed, with all the pieces secured in place. The default nozzle is 0.4 millimeters. In case that’s not enough, you can easily swap it out with a different one. There are 3D printers listed as compatible with high-temperature materials, but most of them can’t do it out of the gate. This isn’t the case with the MK2S, however. With this 3D printer, you can print with all sorts of materials out of the box, courtesy of the E3D V6 hotend – a hotend built specifically for high-temperature performance.

For the most part, there’s no need to use glue or hairspray or other adhesion tricks on the MK2S print bed. It includes a PEI surface for superb adhesion, ensuring that the first layer is always on point, which, in turn, leads to better print results. However, there are certain materials that seem to have a harder time sticking to the surface than other materials. That’s the only time you’ll need to resort to other means to make sure the print bed has enough adhesion.

While the build platform is non-removable, it’s easy to remove finished prints, even the larger ones, once the build platform has cooled down. Similar to the point in the previous paragraph, there are certain materials that will prove to be more stubborn than others and will require some effort before the 3D-printed object comes off the plate. In which case, it’s best to take things slowly, especially if the object is on the large side.

The overall design of the MK2S is simple and functional. Josef Prusa definitely sends out the message that the MK2S is an all-business machine designed to impress people with its performance rather than its looks.

The Features

The MK2S is an open source 3D printer. Josef Prusa is completely committed to the open source movement, sharing his new products’ information shortly after the first unit ships out. Prusa Research is not one of those companies who market their products as open source in order to get more customers, but when asked for the source files, suddenly go the other way and make up lame excuses. Everything about the MK2S is readily available on the internet.

The P.I.N.D.A. probe attached next to the hotend is probably the most notable feature on the MK2S. The small probe has a hand in two operations: First, it’s the key component in the MK2S’s automatic bed leveling technology, helping turn the initial print bed calibration into a trivial matter. And second, it helps the MK2S compensate for skewed axes. In layman’s terms, the latter means the MK2S will compensate if you didn’t manage to put the frame in perfect alignment during the assembly.

In line with its open source nature, the MK2S is compatible with third-party filaments and can be paired with different slicers. The open filament system means you’re free to use filaments from the most popular brands on the market, including the ones from Hatchbox, while the compatibility with different slicers means you can use whatever software that best suits your needs.

While the MK2S has no filament sensor included, it’s easy to stop the operation mid-print in order to change the filament. Not everyone gets excited about filament sensors, though. The people who find it useful are usually beginners who are not yet adept at estimating the amount of filament needed. Those who have been 3D printing for a long time can live without a filament sensor.

For connectivity, the MK2S can connect via USB and SD card. The latter option is the most convenient as well as the most recommended – it works like a charm. And unlike some 3D printers, the MK2S rarely runs into SD card issues, and during the times it runs into an error, the culprit is usually the SD card itself. The MK2S is also compatible with OctoPrint, so there’s that option if you want to be fancy and add convenience to your operation.

The Setup

One of the best ways to learn the ins and outs of 3D printing is to start from scratch, so it’s recommended that you go for the cheaper MK2S kit instead of the pre-assembled one. The first half of this section covers the DIY experience, with the initial setup and calibration in the second half.

Without a doubt, the MK2S is the most beginner-friendly DIY kit on the market. It arrives in a well-secured package that includes everything you need to put it together, including tools and spare parts. There’s no need for soldering during the assembly. It ships with an extremely detailed instruction manual that takes you all the way to the end, as well as a 3D printing handbook, which talks about the basics of 3D printing.

The assembly takes about four to six hours, depending on your familiarity with electronics. For the best experience, you can also use the online version of the manual in tandem with the printed one. That way, you can zoom in on the images, especially in the most technical areas of the assembly. There are also videos on the internet to help you out in certain areas.

As mentioned in the features section, the MK2S has automatic bed leveling, so the print bed calibration is not an issue during the initial setup. Once you’re done with the assembly, the software installation, and the initial calibration, you can start printing right away. The MK2S ships with excellent settings, so there’s no need to tinker with the print settings at the onset. Just load the filament and the test model and watch it go to work.

For the slicer, Prusa Research recommends Slic3r Prusa Edition for intermediate users and PrusaControl for beginners. Both slicers are easy to use. The former, obviously, has more options, while the latter is more straightforward. The MK2S is also compatible with other slicers, including Simplify3D, often regarded as one of the best slicers.

The Performance

The beginner-friendly setup of the MK2S carries over to the print preparation. It’s easy to load the filament, and the LCD interface offers a straightforward operation. The print bed heats up fast as well. The heat distribution is remarkably even – the print bed actually compensates for the corners cooling down at a faster rate than the inner areas, leading to better prints for high-temperature materials.

Out of the box, the MK2S is capable of producing excellent results, teasing you of what it can do when configured to the best settings. Most 3D printers require a significant amount of tinkering at the onset before they can produce a successful print that doesn’t look like crap. That’s not the case with the MK2S.

When fully optimized, the MK2S can create incredibly detailed 3D models with a level of smoothness that can make other 3D printers envious. If set to the best settings, the MK2S can go up against the high-end Ultimaker 3 and more than hold its own. Seriously, the print quality of the MK2S is phenomenal, one of the biggest reasons consumers love it. Also, it’s a very quiet 3D printer, which is amazing considering it’s got an open frame.

The MK2S offers a lot of room for experimentation for intermediate users. It has a good build volume, so you’re not just limited to small items. And as mentioned, it has an open filament system, which allows you to experiment with more advanced materials. The MK2S can produce excellent results with all sorts of filaments, provided it’s got the correct print settings for the material being used.

Though the MK2S has a single extruder setup, it’s still possible to print an object with two colors, but it needs effort on your part. The MK2S has a pause-resume function. So, for a multi-color print, you can manually pause the print and change the filament mid-print. Using the GCode file, you can also set it to stop at a specific point in the print so you can change the filament. Both methods are not the most convenient, but they get the job done.

Tech SpecsProsCons
Resolution: 50 microns

Volume: 9.8 x 8.3 x 8 in

Filament: 1.75 mm

Type: ABS, PLA, Nylon, HIPS, PETG, Flexible, and others

Weight: 14 lb

Connect: USB, SD card

· Open source

· Easy to assemble (DIY kit)

· Large community

· Outstanding print quality

· Automatic mesh bed leveling

· Heated print bed with good adhesion

· Open filament system

· Comprehensive instruction manual

· Reliable customer support

· No enclosure

· Non-removable build plate

The Verdict

The MK2S is one of the best 3D printers that you can get today, edging out some of the more expensive products on the market. If you want a 3D printer that’s easy to use, prints extremely well, and has a large community, this product is for you. It’s an excellent entry-level 3D printer for beginners and a reliable primary 3D printer for hobbyists.

Rating: 4.8/5