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  1. 2 and 2.5 mm allen key
    • 2 and 2.5 mm allen key

    • Needle-nose pliers

  2. New spool holder ( black color) Older spool holder (orange color)
    • New spool holder ( black color)

    • Older spool holder (orange color)

    • Heatbed-cable-cover

    • Both versions of the spool holder have the same functionality.

  3. M4x10 with dome head (2 pcs)
    • M4x10 with dome head (2 pcs)

    • 12V/240W Power supply with cover

  4. Using 2.5mm Allen key, tie the PSU to the frame. Don't tighten the M4x10 screws completely, we will get to that later.
    • Using 2.5mm Allen key, tie the PSU to the frame. Don't tighten the M4x10 screws completely, we will get to that later.

  5. Starting mid of August 2017 is MK2S  kit shipped with redesigned PSU-Y-Part !!! Note this part is already assembled on the Y-axis frame. This photo is just to highlight changes in the design.
    • Starting mid of August 2017 is MK2S kit shipped with redesigned PSU-Y-Part !!!

    • Note this part is already assembled on the Y-axis frame. This photo is just to highlight changes in the design.

    • Older design has deeper holes for nuts with M3x18 bolts.

    • Newer design has shallow holes for nuts with M3x25 bolts.

    • In case M3x25 bolts aren't included in the bag 7. PSU & HB please use bag 9. SPARE.

  6. M3x18 or M3x25 bolts (2 pcs) M3w washers (2 pcs)
    • M3x18 or M3x25 bolts (2 pcs)

    • M3w washers (2 pcs)

    • M3n nuts (2 pcs)

    • Insert M3n nuts in PSU-Y-part nut traps.

    • To insert nuts inside traps, you can use similar "on screw" technique as for the extruder assembly. For more go back to 1. Introduction, Step 8.

  7. Using 2.5mm allen key, tie the PSU-Y-part to the PSU-cover. Return to the screws on the frame from Step 4 and tighten them as well. See the last picture. If there is a gap, use the bolts to contract it.
    • Using 2.5mm allen key, tie the PSU-Y-part to the PSU-cover.

    • Return to the screws on the frame from Step 4 and tighten them as well. See the last picture.

    • If there is a gap, use the bolts to contract it.

  8. Guide the low voltage cables from the PSU under the threaded rods to the other side of the frame as shown in the picture. Tie the low voltage power cables to both threaded rods.
    • Guide the low voltage cables from the PSU under the threaded rods to the other side of the frame as shown in the picture.

    • Tie the low voltage power cables to both threaded rods.

    • Do not tighten them too much, otherwise you can damage cable insulation.

  9. Check the switch position on the side of the PSU if it's in correct position. Make sure that the power supply is not connected to mains!
    • Check the switch position on the side of the PSU if it's in correct position.

    • Make sure that the power supply is not connected to mains!

    • Correct position means that the switch is on the side with your mains voltage. (If you have 110/120 V mains [mostly America] the switch has to be on the left, if you have 220/230 V [Europe and the rest of the world] the switch should be on the right ).

    • You can change the switch position with flathead screwdriver.

    • This is very important part, if the power supply is configured incorrectly it can be damaged!

  10. Unpack your heatbed and check, which version you have:
    • Unpack your heatbed and check, which version you have:

    • without soldered cable, please proceed to Step 11

    • with soldered cable, please proceed to Step 21

  11. For the following step please prepare: Heatbed MK42 12V (1x)
    • For the following step please prepare:

    • Heatbed MK42 12V (1x)

    • Power cable (1x)

    • M3x10 screw (2x)

    • M3w washer (2x)

    • M3nN nylock nut (2x)

    • IT IS VERY IMPORTANT to connect the power cable correctly. Before you start the assembly have a look at the pins. The one on the left with "GND" sign must be connected to the BLACK WIRE.

  12. Place the black wire above the pin with "GND" sign. Make sure you are using the rounded connector. Place the washer above the rounded cable connector. Press the M3x10 screw through all parts.
    • Place the black wire above the pin with "GND" sign. Make sure you are using the rounded connector.

    • Place the washer above the rounded cable connector.

    • Press the M3x10 screw through all parts.

    • Hold the screw and carefully turn the heatbed upside down.

    • Place the M3nN nut on the top of the M3 screw and tighten it slightly.

    • Turn the heatbed back, using pliers and Allen key tighten the screw. We need to adjust cable position in the next step, therefore do not tighten the screw too firmly.

    • Repeat this procedure for the second (red) wire.

  13. Before proceeding further, please check again the cable is connected correctly to the heatbed. BLACK wire must be connected to the "GND"
    • Before proceeding further, please check again the cable is connected correctly to the heatbed.

    • BLACK wire must be connected to the "GND"

    • RED wire must be connected to the "VCC"

    • The cable cover, which will be applied later requires the connectors to be slightly inclined towards each other. Press them gently, but leave a gap between them.

    • Now, tighten both screws using the Allen key and the pliers.

  14. For the following steps, please prepare:
    • For the following steps, please prepare:

    • Heatbed MK42 (1x)

    • Textile sleeve (1x)

    • M3n nut (3x)

    • M3x10 screw (3x)

    • Heatbed-cable-cover (1x)

    • In case the power cable is fixed by screws (not soldered) the heatbed-cable-cover slightly differs from the picture, but the following assembly process is identical.

  15. Insert M3n nuts in the printed part. In case you can't press the M3n nut in, don't use excessive force. Take the M3 bolt and  thread it from the opposite side of the printed part, as you tighten the screw, it will pull the nut in. Be careful not the break the printed part during tightening. In case the power cable is fixed by screws (not soldered) the heatbed-cable-cover slightly differs from the picture, but the following assembly process is identical.
    • Insert M3n nuts in the printed part.

    • In case you can't press the M3n nut in, don't use excessive force. Take the M3 bolt and thread it from the opposite side of the printed part, as you tighten the screw, it will pull the nut in. Be careful not the break the printed part during tightening.

    • In case the power cable is fixed by screws (not soldered) the heatbed-cable-cover slightly differs from the picture, but the following assembly process is identical.

  16. Place the heatbed-cable-cover on the heatbed to cover the soldered cables and LED. Tighten the cover to the heatbed using M3x10 screw and Allen key. Be careful not to pinch (break) any wires from the heatbed!
    • Place the heatbed-cable-cover on the heatbed to cover the soldered cables and LED.

    • Tighten the cover to the heatbed using M3x10 screw and Allen key. Be careful not to pinch (break) any wires from the heatbed!

  17. Do not stretch the black/white thermistor cable, leave some slack under the heatbed, so when the heatbed moves during print, the cable won't get stretched resulting in disconnection from the centre of the heatbed. Guide the black thermistor cable next to the heatbed heater cable and wrap it few times around (see the photo). The thermistor cable is in black or white colour, their functionality is the same.
    • Do not stretch the black/white thermistor cable, leave some slack under the heatbed, so when the heatbed moves during print, the cable won't get stretched resulting in disconnection from the centre of the heatbed.

    • Guide the black thermistor cable next to the heatbed heater cable and wrap it few times around (see the photo).

    • The thermistor cable is in black or white colour, their functionality is the same.

  18. Use the textile sleeve and wrap the cables from the heatbed. Start by few centimeters of the sleeve behind the heatbed cover. When the first "wrap" is ready, slide it inside the heatbed cover. Ensure it is at least 5-6 mm.
    • Use the textile sleeve and wrap the cables from the heatbed. Start by few centimeters of the sleeve behind the heatbed cover.

    • When the first "wrap" is ready, slide it inside the heatbed cover. Ensure it is at least 5-6 mm.

    • Before you continue with wrapping the sleeve, we need to fix it in the cable cover. Please proceed to the next step.

  19. Place second part of the cover on the top of the  textile sleeve. Make sure the thermistor cable is in the middle going through a cutout in the printed part!!! Otherwise, you will pinch and possibly break the cable!!! Insert two screws M3x10 and tighten them, proceed with caution and tighten both screws equally.
    • Place second part of the cover on the top of the textile sleeve.

    • Make sure the thermistor cable is in the middle going through a cutout in the printed part!!! Otherwise, you will pinch and possibly break the cable!!!

    • Insert two screws M3x10 and tighten them, proceed with caution and tighten both screws equally.

    • Don't tighten the screw completely on one side and then on the other (see the second picture)!

    • Your tightened cover should look like the last picture.

  20. Now, finish wrapping the cable into the textile sleeve.
    • Now, finish wrapping the cable into the textile sleeve.

    • When done, slightly twist the sleeve (not the cables inside). The sleeve will evenly wrap all around the cable bundle.

  21. If you assembled the optional nuts on the  Y-belt holder screws, you have to remove them.
    • If you assembled the optional nuts on the Y-belt holder screws, you have to remove them.

    • Remove the M3 nuts highlighted in the picture.

    • Remove only the nuts! The screws M3x12 must remain in place. You will need them to connect the heatbed and belt holder.

  22. M3x8r screws (4 pcs)
    • M3x8r screws (4 pcs)

    • Heatbed comes with the print surface (yellowish foil) already stuck on so DO NOT REMOVE IT and take extra care to prevent any damage to the surface.

  23. Using 2mm allen key, tighten the heatbed to the Y-carriage. Tighten the screws with care. The threads inside the heatbed can be easily damaged!
    • Using 2mm allen key, tighten the heatbed to the Y-carriage.

    • Tighten the screws with care. The threads inside the heatbed can be easily damaged!

    • The screws should fit directly into the threads, if they dont, you may have turned the Y-carriage upside down, see Chapter 2. Y-axis assembly for the correct assembly.

  24. Tighten the Y-belt holder to the heatbed using the supplied 2.5 mm Allen key. Make sure that the M3x12 screws are screwed into the heatbed and no space is left between the nut on the heatbed and the Y-carriage.
    • Tighten the Y-belt holder to the heatbed using the supplied 2.5 mm Allen key.

    • Make sure that the M3x12 screws are screwed into the heatbed and no space is left between the nut on the heatbed and the Y-carriage.

    • Tighten the screws with care. The threads inside the heatbed can be easily damaged!

    • If you have the Y-belt-holder with a slot, make sure that the screws are in the middle as shown in the picture.

  25. In case you have the heatbed cable cover already assembled (heatbed without soldered cable) please skip to Step 31 M3x8r screw (1 pc)
    • In case you have the heatbed cable cover already assembled (heatbed without soldered cable) please skip to Step 31

    • M3x8r screw (1 pc)

    • M3 nut (1 pcs)

    • Lead the black thermistor cable under the heatbed heater cable and wrap it few times around (see the photo).

    • Do not stretch the black thermistor cable, leave some slack under the heatbed, so when the heatbed moves during print, the cable won't get stretched resulting in disconnection from the centre of the heatbed.

    • Note the black cable from the heatbed can be also in white version, however, their function is the same (see the second photo).

  26. Insert M3n nut in place.
    • Insert M3n nut in place.

  27. Take the piece of filament that came with the parts ( length around 30 cm ). Push it all the way down in the filament holder hole in the heat bed cable cover. If you experience difficulties when inserting the filament use pliers to make a sharp tip on the filament. The filament is for whole harness support. Don't cut it, it'll go all the way with the wires to the electronics.
    • Take the piece of filament that came with the parts ( length around 30 cm ).

    • Push it all the way down in the filament holder hole in the heat bed cable cover. If you experience difficulties when inserting the filament use pliers to make a sharp tip on the filament.

    • The filament is for whole harness support. Don't cut it, it'll go all the way with the wires to the electronics.

  28. Make sure the filament is pointing to the right while the cable holder is oriented  upwards (see the nut) Ensure again your thermistor cable is not stretched under the heatbed and is going along the heatbed heater cable through the heatbed cover. Tighten the part to the heatbed using 2 mm Allen key. Be careful not to pinch (break) any wires from the heatbed!
    • Make sure the filament is pointing to the right while the cable holder is oriented upwards (see the nut)

    • Ensure again your thermistor cable is not stretched under the heatbed and is going along the heatbed heater cable through the heatbed cover.

    • Tighten the part to the heatbed using 2 mm Allen key. Be careful not to pinch (break) any wires from the heatbed!

  29. Use the spiral wrap and wrap the cables from the heatbed including the NYLON. Start by one or two wraps 1 cm behind the heatbed cover. When the first wrap is ready, slide it inside the heatbed cover.
    • Use the spiral wrap and wrap the cables from the heatbed including the NYLON. Start by one or two wraps 1 cm behind the heatbed cover.

    • When the first wrap is ready, slide it inside the heatbed cover.

    • DO NOT cut the filament, you'll need the full length.

  30. Place a zip tie around the heatbed holder to tighten the spiral wrap with cables. There is a channel around the cover designed for the zip tie. Tighten the zip tie, but do not overtighten it! You might pinch (break) the heatbed wires. Also, tighten the zip tie on the side of the cover. Cut the remaining part of the zip tie and continue with wrapping the spiral wrap.
    • Place a zip tie around the heatbed holder to tighten the spiral wrap with cables. There is a channel around the cover designed for the zip tie.

    • Tighten the zip tie, but do not overtighten it! You might pinch (break) the heatbed wires. Also, tighten the zip tie on the side of the cover.

    • Cut the remaining part of the zip tie and continue with wrapping the spiral wrap.

  31. Take a look on the printer from the top side and make sure that lines on heatbed are perfectly parallel with the X axis rods as shown in the picture. If they are not in parallel position, use 17 mm wrench to adjust the M10 nuts to get it correct. Use nuts only on the side close to left Z axis motor.
    • Take a look on the printer from the top side and make sure that lines on heatbed are perfectly parallel with the X axis rods as shown in the picture.

    • If they are not in parallel position, use 17 mm wrench to adjust the M10 nuts to get it correct. Use nuts only on the side close to left Z axis motor.

    • This is extremely important, if they are not parallel, you will have difficulties calibrating later on!

    • If you adjust the nuts, make sure that the M10 threaded rod is all the way down in the slot.

  32. Assemble the spool holders to the top of the frame as shown in the picture. To properly assemble the spool holder, let the "tooth" sit on the frame and then press in the direction of the arrows (rotate backwards, while slightly pressing downwards). Don't try to assemble spool holder by pushing it only from the top. More force is needed and you may damage the holder.
    • Assemble the spool holders to the top of the frame as shown in the picture.

    • To properly assemble the spool holder, let the "tooth" sit on the frame and then press in the direction of the arrows (rotate backwards, while slightly pressing downwards).

    • Don't try to assemble spool holder by pushing it only from the top. More force is needed and you may damage the holder.

    • Almost there! You're one step away from finishing! Continue by connecting the electronics in the next chapter - 8. Electronics assembly

Finish Line

552 other people completed this guide.

Josef Prusa

Member since: 01/05/2015

141 Guides authored

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11 Comments

45 minutes..... All going well!

James Miller - Reply

About 1 hour; struggled mostly with the sunken nuts to attach PSU.

Codrin Kruijne - Reply

I found that the m3x18 screw were too short. (steps 5 & 6) Needed m3x25 from spares.

RICHARD GUTHRIE - Reply

The M3x18 are not too short - the problem is the nuts don't go all the way in the traps even when tapped as described in the instructions.

(As Murphy once said: "If it doesn't work - don't force it. Use a bigger hammer." LOL!)

Joke aside, the way I did it was the following:

1. (before attaching the PSU) use one of the longer screws from the spare parts package to catch the nut;

2. pull the nut in the trap by turning the screw until resistance became greater than normal; that's a hint that the nut reached the traps' end;

3. remove the long screw;

4. attach the PSU. The screws come out of the nuts just a bit...exactly as they should.

Ferdinand Badescu - Reply

After assembly I noticed that the left side of my black frame sits about 1-2mm higher than the right side. I made ABSOLUTELY SURE that the frame was tightened quite hard on both sides, and it was all even at that point. Is this common?

Jason Wright - Reply

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