⬢Torx TX10 key

⬢Torx TX6 key

⬢Torx TX8 key

⬢2.5 mm Allen key

⬢Universal wrench

⬢Nose pliers

⬢Side cutters recommended for cutting zip ties

⬢Prusa lubricant (1x) supplied with your printer

⬢PG-assembly-adapter (1x)

The following step is only necessary if you have a filament loaded in the current toolhead.

⬢Unload the filament from the hotend. On the screen, navigate to Filament -> Unload Filament and select the tool, you want to working on.

⬢Remove the filament from the hotend. It is not necessary to completely remove it from the printer. Just a few centimeters (inches) above the extruder.

⬢Cool down the printer to room temperature. On the screen, navigate to Preheat -> Cooldown.

⬢On the printer screen, navigate to Control -> Pick/Park Tool -> Park Current Tool.

⬢Turn the power switch OFF (symbol "O").

⬢From the rear side of the printer, unplug the PSU cable.

⬢On the selected toolhead you want to work on:

⬢On the selected toolhead you want to work on:

⬢Using a T10 screwdriver, remove the M3x30 screw holding the fan-shield.

⬢Turn the nextruder with the print fan facing up.

⬢Remove the M3x8rt screws from the tool-changer using a T10 screwdriver..

⬢Unplug the toolchanger cable. Press the safety latch while disconnecting the connector.

⬢Remove the toolchanger from the Nextruder.

⬢Loosen the M3x16 screw, just a few turns are enough to release the dwarf-cover-door. No need to removing the screw completely.

⬢Open the dwarf-cover-door widely.

⬢Remove two M3x20rT screws from the heatsink fan using a T10 screwdriver.

⬢Push the idler-swivel upward.

⬢Pull the idler-lever downward in order to release tension on the gearbox.

⬢Fully loosen three M3x25 screws from the printed gearbox cover. Keep the screws in the assembly, don't remove them completely.

⬢Carefully slide the gearbox assembly off. It is necessary to remove the entire assembly in one piece. This means PG-cover (top plastic cover), PG-ring (brass ring), PG-assembly (metal gears), and main-plate (bottom plastic plate), all joined by M3x25 screws.

⬢Set the gearbox assembly and the extruder motor aside.

⬢Unplug the hotend thermistor cable from the Dwarf board. Press the safety latch while disconnecting the connector.

⬢Unplug the hotend heater cable from the Dwarf board. Press the safety latch while disconnecting the connector.

⬢With a Torx TX 8 key loosen the grub screw in the extruder. Do not remove the screw completely. A few turns are enough to release the hotend assembly in the heatsink.

⬢Carefully pull the hotend assembly out of the heatsink.

⬢At the same time pull the disconnected hotend cables from below the heatsink.

⬢Unplug all remaining cables from the Dwarf board. Press the safety latch while disconnecting each connector.

⬢Remove the heatsink assembly and set it aside.

⬢Remove the two M3x10 screws from the heatsink with a 2.5 mm Allen key.

⬢Separate the heatsink and the print fan.

⬢Set the print fan aside. We will need it later again.

⬢Remove the two M3x30 screws to remove the idler-swivel from the heatsink.

⬢Remove the idler-swivel from the heatsink.

⬢Remove the festo with a universal wrench.

⬢Unscrew the M2.5x6rT screw to remove the Hall filament sensor.

⬢Carefully remove the Hall filament sensor.

⬢Release the set screw from the bottom of the heatsink to remove the NTC thermistor.

⬢Pull the NTC thermistor out from the heatsink.

⬢Very carefully pull the filament sensor out from the heatsink using the needle-nose pliers.

⬢Remove the grub screw from the heatsink.

⬢Place the Hall filament sensor into the similarly shaped pocket in the heatsink.

⬢Fix it with M2.5x6rT screw. Tighten it very carefully, you can crack the electronics board.

⬢Insert the grub screw into the slot closer to the bottom of the heatsink. See the picture.

⬢Insert the Prusa ball holder assembly into the heatsink. Make sure the steel ball part is closer to the side of the heatsink.

⬢Push the assembly into the heatsink.

⬢Tighten the idler-swivel with two M3x30 screws.

⬢The tip of each screw should be flush with the plastic part on the other side.

⬢On the extruder motor side, insert the NTC thermistor into the hole in the heatsink.

⬢Secure it with the M3x4T grub screw. Screw it all the way in. Tighten gently, but firmly using two fingers and the short side of the T6 Torx key. Applying more force may cause permanent damage to the thread.

⬢Align the heatsink with the motor assembly.

⬢Gearbox assembly (1x) you took from Nextruder

⬢PG-assembly-adapter (1x)

⬢Dismantle the gearbox assembly into its component parts:

⬢Using a paper towel clean all the parts from grease.

⬢In the following steps, we will reassemble the entire gearbox assembly to ensure proper installation.

⬢Attach the PG-assembly-adapter on the PG-assembly. Note the pockets for the gears in the adapter.

⬢Slide the PG-ring onto the adapter.

⬢Grasp the entire assembly in one hand so that it can be rotated with the PG-ring.

⬢With the other hand, slide the PG-ring onto the PG assembly in a wobbling motion (move the PG-ring left and right repeatedly) - a quarter turn is enough.

⬢Stop when the surfaces of the gears are approximately flush with the surface of the PG ring.

⬢Attach the main-plate on the heatsink. Note the orientation of the part. Use the cutout for the socket screw as a guide (lower left corner).

⬢Maintain the position of the PG-assembly and attach it on to extruder motor shaft.

⬢Make sure the PG-ring perfectly fits on the socket set screw.

⬢Very gently and freely rotate with the whole PG assembly (PG-assembly-adapter, PG-assembly and PG-ring) until it drops down so that there is minimal gap between the assembly and the main-plate. Do not push on the assembly.

⬢Remove the PG-assembly-adapter.

⬢Attach the PG-assembly-adapter back on the PG-assembly again to verify that all parts are properly seated.

⬢Rotate with the PG-assembly-adapter. The PG assembly must be easy to rotate without having to exert much force.

⬢Remove the PG-adapter. You will no longer need it during assembly. We recommend keeping it for maintenance.

⬢Ensure that the PG-assembly is not sticking out above the PG-ring. It should be positioned lower than the level of the PG-ring's surface or at the same level as the ring.

⬢There must be no gap between PG-ring and the Main-plate. If you see a gap, remove the planetary gear assembly and repositon it again.

⬢Open the Prusa Lubricant. Using the opposite side of the cap, puncture the hole in the opening of the tube.

⬢Apply a small amount of Prusa Lubricant all around the PG-ring and PG-assembly teeth.

⬢Using a paper towel, wipe off any excess lubricant on the front surfaces.

⬢Place the PG-case on the gearbox.

⬢Insert three M3x25 screws into the PG-case, but do not tighten them completely. They will be tightened later.

⬢Close the idler-lever and lock it in position with the idler-swivel.

⬢Plug the load cell sensor cable into the Dwarf board.

⬢Plug the filament sensor cable into the Dwarf board.

⬢Plug the heatsink thermistor cable into the Dwarf board.

⬢Prepare the Tool changer board & print fan assembly.

⬢Align the three metal spacers with the holes in the heatsink, make sure the board and fan cables are guided below the top spacer before you attach the heatsink, so that they are not pinched.

⬢Use the M3x10 screws to secure the heatsink & gearbox assembly to the spacers on the print fan cover. Start with the centre screw, taking care not to pinch any cables.

⬢Attach the hotend fan to the heatsink with its cable positioned as can be seen in the picture.

⬢Secure the heatsink fan with two M3x18rT screws.

⬢Plug the print fan cable into the Dwarf board.

⬢Plug the toolchanger cable into the Dwarf board.

⬢Plug the hotend fan cable into the Dwarf board.

⬢Attach the toolchanger board with the heat shield to the Nextruder.

⬢Secure the fan shield with a M3x30 screw.

⬢Insert the hotend into the heatsink.

⬢Plug in the hotend thermistor cable.

⬢Plug in the hotend heater cable.

⬢Close the printed Dwarf board cover on the Nextruder.

⬢Tighten the M3x12 screw.

⬢Secure the toolchanger with two M3x8rt screws.

⬢Connect the toolchanger cable.

⬢While pushing the hotend into the heatsink, tighten the grub screw with a Torx TX 8 key.

Starting from September 2024, you may receive a new black Fitting M5-4. The assembly and functionality remain identical to the blue one.

⬢Mount the festo on the top of the heatsink.

⬢Gently tighten the festo with a uni-wrench.

⬢Insert the PTFE tube into the festo connector as far as possible. Slighty tug on the PTFE tube to make sure it's firmly secured.

⬢Plug the Dwarf extruder cable to the Dwarf board.

⬢Slide the black nylon plate onto the screws in the Cheese board, and tighten them with a Torx T10 key.

⬢Carefully turn the printer so that the front side is facing towards you.

⬢Take the Nextruder and place it carefully next to the dock.

⬢Place the two metal inserts through the white holes in the dock. The magnets will help you dock the Nextruder.

⬢Check that the Nozzle seal lightly touches the nozzle.

⬢From the rear side of the printer, plug in the PSU cable.

⬢Turn the power switch ON (symbol "I").

⬢Run the tests from the Control - Calibration & Tests menu.

The wizard will test all important components of the printer. The whole process takes a few minutes. Some parts of the wizard require direct user interaction. Follow the instruction on the screen.

⬢Plug in the printer and turn it ON.

⬢Now we need to simulate the movement of the gearbox. On the LCD screen, navigate to Filament - Unload filament.

⬢As soon as the extruder's movement finishes, tighten the three M3x25 screws on the PG-case in the correct order (shown on the picture).

⬢Then loosen the screws slightly and repeat the process, tightening the screws in the correct order. This ensures that the gearbox is seated correctly.