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The Original Prusa i3 MK3S is constantly evolving. Based on your feedback and improvements from Josef Prusa's team, the printer is getting new features and redesigned parts for easier assembly. All the changes are described below. In case you need help, please ask below the particular step in online manual or contact our support team.

  1. Versions of the MK3S manual:
    • Versions of the MK3S manual:

    • 02/2019 - Initial version 3.10

    • 03/2019 - Updated to version 3.11

    • 07/2019 - Updated to version 3.12

  2. 03/2019 - Chapter 2 (Y-axis)
    • 03/2019 - Chapter 2 (Y-axis)

    • PSU holders assembly now depends on the type of the PSU, which is in your kit.

    • 03/2019 - Chapter 7 (HB & PSU)

    • Chapter 7 is now in two versions depending on the PSU type, which is in your kit.

    • New PSU is fully black, old PSU has silver casing.

    • Manual version 3.11

  3. 05/2019 - Chapter 7 (HB & PSU)
    • 05/2019 - Chapter 7 (HB & PSU)

    • Heatbed-cable-cover design improved to prevent collision with the extruder cables, which sometimes occurred. All screws are now facing down.

    • New design with circular holes in the top part. The smaller part has hexagonal holes.

    • Old design with hexagonal holes in the top part. The smaller part has circular holes.

    • Manual version 3.11

  4. 07/2019 - Chapter 1 (Introduction)
    • 07/2019 - Chapter 1 (Introduction)

    • The printer's package contains a lubricant, which is intended for maintenance. No need to use it now the bearings are lubricated. There is a dedicated online manual on how to clean the printer and apply the lubricant. See Printer maintenance tips

    • Several tweaks and new photos across the entire manual.

    • Manual version 3.12

  5. 09/2019 - Chapter 1 (Introduction) Added warning about the ESD protection. Keep the electronics in the bag until needed for the assembly.
    • 09/2019 - Chapter 1 (Introduction)

    • Added warning about the ESD protection. Keep the electronics in the bag until needed for the assembly.

    • 09/2019 - Chapter 5 (Extruder)

    • There is a new hardware revision of the IR-sensor with some optimisations. Filament detection is the same.

    • Manual version 3.13

Finish Line

75 other people completed this guide.

Jakub Dolezal

Member since: 02/20/2017

225 Guides authored


Prusa Research Member of Prusa Research


3 Members

367 Guides authored


Just finished my build this is my first printer

fantastic instructions I had no problems apart from I ran out of sweets

I didn't follow the correct sweet dosage may I suggest when purchasing a printer that you include an option for extra sweets this will stop others having the same problem

ps great product fantastic manual worth every penny who ever put the instructions together is a genius

many thanks s.m.strang

steven strang - Reply

I've built my MK3S this weekend, and the manual was very comprehensive. I did have a couple of minor problems - In chapter 5 I followed the instruction not to mix up M3x20 & M3x18 screws: I kept all the long screws to the side. I didn't realise there were also three M3x14 screws, also easily confused with the M3x18 screws, so I used one of them to secure the FS lever instead of an M3x18. 16 pages later, it said use three M3x14 screws to secure the hotend fan but I only had two so I had to take it all apart again. It might be worth saying to sort all the screws into piles of different lengths beforehand rather than just two types. I also got a bit worried that there was an unused screw hole on the side of the extruder (in the X-carriage near the hotend fan), but I've been told that it is a hold-over from the previous model's limit sensor and therefore no longer used. It might be worth mentioning in section 5 that it's meant to be left unused.

Matthew Meek - Reply

Hi Matthew, thank you for the feedback - we’ll try to make some adjustments.

Filip M - Official Prusa CS -

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