Table of Contents

Original Prusa i3 MK3s

Miron Zadora is lending his printer to the lab

This printer is no longer present

Costs

See costs.

Materials

See Approved filaments

The printer can be used for printing with PLA or PETG filament, with a 1.75mm diameter.
Other filaments have to be discussed on the mailing list. If you wish to print with ABS then additional ventilation will be required to deal with styrene fumes.

TPU or TPE flexible filaments (such as NinjaFlex) may be used but only on the Textured steel sheet or with the use of talcum powder or painters tape on the smooth steel sheet
SMOOTH SHEET WILL GET DAMAGED IN CASE YOU PRINT TPU DIRECTLY ON IT!!! (TPU fuses with the PEI surface)

How to print with TPU filament on the Prusa Mk3s

  1. In PrusaSlicer, select the “Generic FLEX” filament profile
    1. If it is not highlighted, click “Add/Remove fillaments” and in the windows that appeared select
      Printer: (All), Type: FLEX, Profile: Generic FLEX, and tick the box next to Generic FLEX and click Finish
  2. With Generic FLEX selected, go to the Filament Settings tab in PrusaSlicer and modify the nozzle temperature for first layer and other layers to the fillament manufacturer recommended settings
  3. Slice file, and load the filament as before
  4. Swap the smooth steel sheet with the textured steel sheet
  5. Switch from Smooth1 to Textur1 by pressing the knob with the Sheet option highlighted in the main menu
    1. The prusa has a setting in the main menu for switching steel sheet profiles, so that different z-leveling values can be saved separately.
  6. Loosen the feeder gear tension to the lowest it will go with an allen key: https://help.prusa3d.com/article/idler-screw-tension_177367
    1. Make sure the screw is still fully in the nut on the right side of the head
  7. To be safe, turn down the printing speed to about 60% by turning the knob counterclockwise while in the main menu
    1. you may find this is not necessary if the filament sticks well
    2. if you don't want to do this every print, you can modify the speed settings in prusaslicer instead
  8. When done, change the sheet, sheet profile, unload filament and tighten the idler screw so that it is flush with the surface

Rules

Software

PrusaSlicer - very user friendly, has a simple and an expert mode, suited for new and experienced users alike

If you wish to use a different slicer you can ask on the mailing list. But unless you have a very good reason to use a different one it's advised to stick with the listed options.

Calibration

The Prusa MK3s will automatically calibrate before every print.
Do not use the calibration option on your own without a previous discussion on the mailing list.

Different materials may require different Z-offsets. If you want to change the Z-offset, make sure to first note down the previous setting and change it back when you're done.

Firmware

Printer is using an unmodified version of the the original Prusa MK3s firmware. We have no intention of changing this.

Printing Instructions

Unless you are experienced with 3D printing it is highly recommended that you ask on the mailing list for help with your first few prints.

If you want some guidance here is a perfect quick start guide from Prusa Research: https://www.prusa3d.com/new-user-mk3/

Revo RapidChange nozzles

It's now possible to print more detailed or larger prints as the new nozzles can be quickly unscrewed by hand and swapping them takes less then a minute.

The normal nozzle size is 0.4mm, and is marked with a RED cover. Make sure you have the correct one installed before starting a print and please swap back to 0.4 when you're finished with a differently sized one

We currently have 0.25, 0.4, 0.6 and 0.8mm brass nozzles, hopefully hardened ones for abrasive materials will be released later.

Documentation

https://prusa3d.com/downloads/manual/prusa3d_manual_mk3_en.pdf