The range of 3D printers on the market has grown hugely since we started this site, with new models appearing all the time. There are a few that stand out as being especially influential though, and the Prusa i3 MK3S+ is one of those. When it first hit the market it offered an unbeatable balance of features, performance and value. It popularised the style of printer that moves the bed in the X and Y axes, with the Z axis handled by a rising beam that rides on the doorframe-style upper section. It also offered a lot of options for people who wanted one – from a fully assembled device ready to print out of the box, to a list of required hardware and free files for its printable parts.
Prusa Research haven’t let the grass grow under their feet, and the current version is the i3 MK3S+. This is an incremental upgrade over the 2019 MK3S – there’s also an upgrade kit available if you already have the 3S – but it’s supposed to be a step forward in performance and reliability. So how does it stack up?
What’s In The Box?
The easiest – and most expensive, of course – way to get printing with the Original Prusa i3 MK3S+ (and that’s the last time I’m bothering with that mouthful) is to order one fully assembled. A ready to go i3 costs £891.58 direct from Prusa, compared to £693.23 for the kit, so the price difference is significant, but if you’re not a tinkerer the prebuilt one does guarantee you’ll get a printer that’s properly put together and works straight out the box.
There’s no doubt, it is well put together. The early i3 models were a bit flimsy, with the Z axis frame built around threaded rod, but the MK3 switched to aluminium extrusions and that made a huge difference to the stability of the design. It’s not going to vibrate itself out of alignment as it prints; in fact it’s rock solid. Everything is properly secured and perfectly aligned; even the wiring is neat and tidy.
All MK3 versions have an extensive feature list, and it’s getting longer with each new iteration. The MK3S adds a magnetic print bed with a detachable, flexible sheet that makes removing completed prints effortless. It has upgraded, quieter stepper motors, power loss recovery to restart interrupted prints, a SuperPINDA temperature sensor and upgraded IR filament sensor.
How Does It Print?
The MK3S+ is an easy printer to work with. Filament loads automatically – just poke the end into the extruder, and a sensor will detect it and start turning the drive gear. It can handle a wide range of filament types too, including PLA, ABS and nylon. It comes with its own very competent slicing software, and also works well with Cura.
When it comes to actual printing there are a wide variety of layer thickness and speed settings, with slower speeds giving truly excellent results. If you’re in a hurry you can turn the speed up, but some resonance distortions can become visible – our advice is to only use this if you’re really in a hurry. Otherwise the extra time taken to print at a slower speed is well worthwhile. Average errors were well below 0.1mm, and while there’s some occasional fine stringing every print cleaned up easily and well.
This is an expensive printer for most hobbyists, but if you’re looking for the best possible print quality without spending upwards of £2,000, or you want a printer that can easily be upgraded and has a wide range of accessories available, the Prusa MK3S+ is an ideal choice. It’s been the inspiration for a whole class of printers, but none of its offspring have caught up with it yet. This is hard to beat if you want amazing quality at a reasonable price.