Next Day Reprap

Prusa Mendel Build Manual

Prusa Mendel Build Manual

Step by Step Detailed Instructions for building your Prusa Mendel

reprap prusa mendel kit

Prusa Mendel Build Manual

Reprap Prusa Mendel Build Manual

Reprap Prusa Mendel Build Manual Contents

Reprap Prusa Mende Build Manual

A fully comprehensive step by step guide for building your Prusa Mendel 3D Printer Kit. Getting up and running and 3D printing.

If you wish you can download the full PDF Reprap Prusa Mendel Build Manual on our 3D Printer Downloads page.

The following instructions will take you through every step to build and commission your printer. All the parts required are included in your kit. We recommend you read through the complete manual to familiarize yourself with the process before starting. We also recommend you read the following important points about your kit and the parts it contains.

Note about Plastic Parts

All our plastic parts are printed on the same printers that you will be building. The parts are built at varying densities to suit their application. Some are required to be stronger than others.

You should take special care when inserting bearings or nuts into plastic part recesses. Some parts have more fragile areas. When inserting bearings ensure the part is held firmly on a flat surface, ensuring there is no force on fragile areas. Then push the bearing into the recess, increase the force until the bearing clips into place. If you cannot get the bearing in place, using a pair of large pliers and a small amount of force should ensure they go all the way in, always ensure you keep the bearing level and avoid pushing in at an angle.

Plastic parts will wear over time. You should regularly follow the the maintenance tips in the manual to ensure your printer remains reliable. We recommend that if your first purpose is not to build yourself or a friend a second printer then you should print a spare set of parts for your own. This will help you in the future should a critical part wear out. This is also a great way to familiarize yourself with the print process and all the files you need are included on the CD-Rom.



Health & Safety

High voltage High Temperature

This is a kit of components for assembly into a 3D Printer by the end user. Building and using the printer is potentially very dangerous as it involves electricity and high temperatures.

Building the printer will require a certain amount of physical dexterity, common sense and a thorough understanding of what you are doing. We have provided fully comprehensive build documentation to enable you to build your Prusa Mendel 3D Printer Kit in a safe manner, we have pre assembled many of the more complicated components, such as the electronics to make it easier for you.

However ultimately we cannot be responsible for your health and safety whilst building or operating the printer, with that in mind be sure you are confident with what you are doing prior to commencing with building or buying. Read all of the manual to enable you to make an informed decision.

Building and operating involves electricity, so all necessary precautions should be taken and adhered to, the printer runs on 12V supplied by a certified power supply, so you shouldn’t ever have to get involved with anything over 12V but bear in mind there can still be high currents involved and even at 12V they shouldn’t be taken lightly.

High temperatures are involved with 3D Printing, the Extrusion nozzle of the hot end runs at 230°C, the heated bed runs a 110°C and the molten plastic extruded will initially be at around 200°C, so special care and attention should be made when handling these parts of the printer during operation.

We wouldn’t recommend leaving your printer running un attended, or at least until you are confident to do so. We cannot be held responsible for any loss, damage, threat, hurt or other negligent result from either building or using the printer.



Prusa Mendel Parts Help and Support


0.0 Prusa Mendel Build Manual Bill of Materials

Reprap Prusa Mende Build Manual
The complete list of components supplied in the Prusa Mendel 3D Printer Kit

0.0 Ancillaries

  • 0.1 Full Printed Prusa Mendel Build Manual
  • 0.3 Software CD/Flash Drive
  • 0.4 33M 20mm Kapton Tape
  • 0.5 Cable Ties
  • 0.11 .25 Kg White 3mm ABS Filament
  • 0.12 Silver Tape
  • 0.13 Cable Tidy

1.0 Electronics

1.1 Fully assembled RAMPS 1.4 Wired & Soldered with Hot end power & Thermistor cables attached, complete with Pololu Steppers and attached to the Arduino Board.

Prusa Mendel Bill of Materials Fully Assembled RAMPS 1.4


1.2 RAMPS Power Cables

Prusa Mendel Bill of Materials RAMPS Power Cables


1.3 3x Mechanical Endstops with Completed Wiring

Prusa Mendel Bill of Materials Mechanical Endtsops


1.4 550W ATX PSU (240v)

Prusa Mendel Bill of Maerials 500W ATX PSU


1.5 ATX Power Supply Adaptor (to switch PSU on)

Prusa Mendel Bill of Materials ATX Power Supply Switch


1.6 Reprap V2 Heatbead with Surface Mount LEDs/Resistor & Soldered Power Cable (inc Thermistor)

Prusa Mendel Bill of Materials Reprap V3 Heat Bed


1.7 5 x Nema 17 Stepper Motors with Crimps & Connectors

Prusa Mendel Bill of Materials Crimps & Connectors


1.8 Fully assembled Hot End wired for Power & Thermistor with Mini Fit Molex connectors

Prusa Mendel Bill of Materials Hot End


1.9 UK Mains Power Lead (Kettle Type) & 1M USB 2.0 Cable

Prusa Mendel Bill of Materials Power Lead


2.0 Rod

  • 2.1 6x 300mm A2 Stainless 1.25mm Pitch Threaded Rod
  • 2.2 2x 450mm BZP 1.25mm Pitch Threaded Rod
  • 2.3 1x 320mm BZP 1.25mm Pitch Threaded
  • 2.4 6x 380mm BZP 1.25mm Pitch Threaded Rod
  • 2.5 2x 330mm Bright Stainless Steel Round Rod
  • 2.6 2x 400mm Steel Round Rod
  • 2.7 2x 400mm Steel Round Rod
  • 2.8 1x 19mm Steel Round Rod ( Extruder Idler)
  • 2.9 1x 50mm Threaded Rod (X Idler)
Prusa Mendel Bill of Materials Smooth Rod


3.0 Nuts & Bolts

  • 3.1 6 x M2 16mm Hex Socket Bolts
  • 3.2 30x M3 10mm Hex Socket Bolts
  • 3.3 15x M3 20mm Hex Socket Bolts
  • 3.4 2x M3 40mm Hex Socket Bolts
  • 3.5 2x M4 50mm Hex Socket Bolts
  • 3.6 2x M4 45mm Hex Head Bolts
  • 3.7 4x M4 40mm Countersunk Hex Socket Bolts
  • 3.8 6x M8 30mm Fender/Penny Washers
  • 3.9 6x M2 Nuts
  • 3.10 28x M3 Nuts
  • 3.11 8x M4 Nuts
  • 3.12 86x M8 Nuts
  • 3.13 2x M3 Nylock Nuts
  • 3.14 1x M8 Nylock Nuts
  • 3.15 12x M2 Washers
  • 3.16 56x M3 Washers
  • 3.17 16x M4 Washers
  • 3.18 100x M8 Washers
  • 3.19 1x Hobbed Bolt
  • 3.20 1x M3 10mm Grub Screw (Extruder Small Gear)
Prusa Mendel Bill of Materials Nuts and Bolts


4.0 Bearings, Pulleys & Couplings

4.1 12x LM8UU Bearings (1 Spare)

Prusa Mendel Bill of Materials 12x LM8UU Bearings


4.2 9 x 608ZZ Bearings (1 Spare)

Prusa Mendel Bill of Materials 9 x 608zz bearings


4.3 2x 12 tooth T5 XL Aluminum Pulleys

Prusa Mendel Bill of Materials 2x T5 12 tooth XL Alu Pulleys


4.4 2x Machined Aluminium 8mm to 5mm Couplings

Prusa Mendel Bill of Maerials 2x 5mm to 8mm Rigid Machined Couplings


5.0 Springs

5.1 4x Heat Bed Springs

Prusa Mendel Bill of Materials 4x Heat bed Springs


5.2 2x Z Axis Springs

Prusa Mendel Bill of Materials 2x Z Axis Springs


5.3 2x Extruder Springs

Prusa Mendel Bill of Materials 2x Extruder Springs


6.0 Timing Belts

6.1 2x 1M T5 6mm Timing Belts

Prusa Mendel Bill of Materials 2x 1M T5 6mm Timing Belts


7.0 Build Plate / Bed

7.1 Laser Cut Aluminum Build Bed

Laser Cut Aluminum Build Bed


7.2 Laser Cut Ply Build Bed Top

Prusa Mendel Bill of Materials Laser Cut Ply Build Bed Top


7.3 6 x 51mm Bull Dog Clips



7.4 Build Plate Top Mirror 225mm x 225mm

Prusa Mendel Bill of Materials Laser Cut Ply Build Bed Top


8.0 Printed Parts

8.1 4x Bar Clamps

Prusa Mendel 4x Bar Clamps


8.2 2 x Rod Clamps

Prusa Mendel 2 x Rod Clamps


8.3 4 x Belt Clamps

Prusa Mendel 4 x Belt Clamps


8.4 3 x Endstop Holder

Prusa Mendel 3 x Endstop Holder


8.5 4 x LM8UU Bearing Pillows

Prusa Mendel 4 x LM8UU Bearing Pillows


8.61 x Extruder 8.6.1 1 x Extruder Idler
8.6.2 1x Extruder Large Gear
8.6.3 1x Extruder Small Gear

Prusa Mendel 1 x Extruder


8.7 2 x Frame Vertex

Prusa Mendel 2 x Frame Vertex


8.8 4x Frame Vertex with Foot

Prusa Mendel4x Frame Vertex with Foot />
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8.9 2x Lower Z Mount

Prusa Mendel Bill of Materials 2x Lower Z Mount


8.10 1 x X Motor Mount

Prusa Mendel  1 x X Motor Mountt


8.11 1 x X Idler

Prusa Mendel Bill of Materials 2 x 1M T5 6mm Belt


8.12 1x Y Motor Mount

Prusa Mendel 1x Y Motor Mount


8.13 2x Z Motor Mounts

Prusa Mendel Bill of Materials 2x  Z Motor Mounts


8.14 1 x X Carriage

Prusa Mendel 1 x X Carriage


8.15 1 x Hot End Clamp

Prusa Mendel  Hot End Clamp


8.16 1 RAMPS Box

Prusa Mendel RAMPS Box


Now we have familiarised ourselves with the Prusa Mendel 3D Printer Kit contents we can now proceed to 2.0 Reprap Prusa Mendel Frame Assembly .





Prusa Mendel Parts Help and Support


2.0 Frame Assembly

2.1 Parts Required

Parts Required
  • 2 x Lower Z Mount
  • 2 x Frame Vertex
  • 4 x Frame Vertex
  • 4 x Bar Clamp
  • 1 x Y Motor Mount
  • 2 x Z Motor Mount
  • 6 x 380mm Threaded Rod
  • 4 x 300mm Threaded Rod
  • 1 x 320mm Threaded Rod
  • 2 x 450mm Threaded Rod
  • 4 x M8 Fender Washers
  • 80 x M8 Washers
  • 78 x M8 Nuts
  • 4 x 608 Bearings

2.2 Assembly

Step 1

Take one Lower Z Mount and push in one 608 Bearing. Push down against a solid flat surface to ensure the bearing sits flush in the plastic part.

Reprap Prusa Mendel Frame Assembly Step 1


Step 2

Take one 380mm Threaded Rod and thread on the following parts from left to right. M8 Nut/M8 Washer/Vertex with Foot/M8 Washer/M8 Nut/M8 Nut/M8 Washer/Lower Z Mount/M8 Washer/M8 Nut/M8 Nut/M8 Washer/Vertex with Foot/M8 Washer/M8 Nut. Space the parts as in the photo below. Leave approximately 5mm of thread showing on the end of the rods. The Lower Z mount should be central on the rod. Do not over tighten the M8 Nuts. Leave them finger tight at this stage.

Reprap Prusa Mendel Frame Assembly Step 2


Step 3

Take one 380 mm Threaded Rod and thread on the following parts from left to right. M8 Washer/M8 Nut/M8 Nut/M8 Washer/Frame Vertex/M8 Washer/M8 Nut. Space apart as in the photo below.

Reprap Prusa Mendel Frame Assembly Step 3


Step 4

Take another 380 mm Threaded Rod and thread on the following parts from left to right. M8 Nut/M8 Washer/M8 Nut. Push this rod through the Frame Vertex from step 3 and attach an M8 washer and M8 nut to secure it. Your component should look like the photo below.

Reprap Prusa Mendel Frame Assembly Step 4


Step 5

Take your component from step one and thread it on to the component from step four. Add an M8 washer and M8 nut to the end of the threaded rods. Your component should look like the photo below.

Reprap Prusa Mendel Frame Assembly Step 5


Step 6

Now measure the distance between the inside edges of the printed frame vertices. Make this gap 290 mm. Loosely tighten the M8 nuts against the vertices and adjust evenly until all three sides are 290mm. The Lower Z Mount should be left loose and approximately in the centre of the rod. Check your measurements and tighten the M8 nuts against the vertices ensuring your frame side is stiff and even.

Reprap Prusa Mendel Frame Assembly Step 6


Step 7

Repeat steps 1 to 6 and you should now have two frame sides. Place these to one side

Reprap Prusa Mendel Frame Assembly Step 7


Step 8

Take one 300mm Threaded Rod and thread on the following parts from left to right. M8 Washer/M8 Nut/M8 Nut/M8 Washer. This component should look like the photo below.

Reprap Prusa Mendel Frame Assembly Step 8


Step 9

Take one 300mm threaded rod and thread on the following parts from left to right. M8 Washer/M8 Nut/M8 Nut/M8 Washer/Bar Clamp/M8 Washer/M8 Nut/M8 Nut/M8 Nut/Fender Washer/M8 Washer/608 Bearing/M8 Washer/Fender Washer/M8 Nut/M8 Nut/M8 Nut/M8 Washer/Bar Clamp/M8 Washer/M8 Nut/M8 Nut/M8 Washer.This component should look like the photo below.

Reprap Prusa Mendel Frame Assembly Step 9


Step 10

Take two 300mm threaded rods. Thread the Y Motor Bracket on to both rods as in the photo below.

Reprap Prusa Mendel Frame Assembly Step 10

Then thread all of the following parts on the upper threaded rod (The upper rod is the one that is furthest to the longer flat edge on the Y Motor Bracket), from left to right. M8 Washer/M8 Nut/M8 Nut/M8 Washer/Bar Clamp/M8 Washer/M8 Nut/M8 Nut/Fender Washer/M8 Washer/608 Bearing/M8 Washer/Fender Washer/M8 Nut/M8 Washer/Y Motor Bracket/M8 Washer/M8 Nut/M8 Nut/M8 Washer/Bar Clamp/M8 Washer/M8 Nut/M8 Nut/M8 Washer.

Then Thread the following parts on the lower threaded rod, from left to right. M8 Washer/M8 Nut/M8 Nut/M8 Washer/Y Motor Bracket/M8 Washer/M8 Nut/M8 Nut/M8 Washer. This component should look like the photo below.

Reprap Prusa Mendel Frame Assembly Step 10b


Step 11

Take two 450 mm threaded rods and thread them each with the following parts from left to right. M8 Washer/M8 Nut/M8 Nut/M8 Washer. Space them as in the photo below (leave approximately 100mm of threaded rod on each end).

Reprap Prusa Mendel Frame Assembly Step 11


Step 12

Take one 320 mm threaded rod and thread it with the following parts from left to right. M8 Washer/M8 Nut/M8 Nut/M8 Washer. Space them as in the photo below.

Reprap Prusa Mendel Frame Assembly Step 12


Step 13

The next steps will take you through joining your two triangle components together using the rods created in steps 8 to 12. Take one of the frame sides you completed in step seven and the threaded rod from step from step 12. Slide the threaded rod through the lower Z mount and add an M8 Washer and M8 Nut to secure it. Ensure the Lower Z mount has the 608 bearing facing up.

Reprap Prusa Mendel Frame Assembly Step 13


Step 14

Take the rod from step ten and thread through the vertex with foot as the photo below. Use an M8 Washer and M8 Nut on each rod to secure it. Ensure the longer flat edge of the Y Motor Bracket is at the bottom.

Reprap Prusa Mendel Frame Assembly Step 14


Step 15

Take the rod from step eight and thread through the lower hole on the second vertex foot. Use an M8 Washer and M8 Nut to secure it.

Reprap Prusa Mendel Frame Assembly Step 15


Step 16

Take the rod from step nine and thread through the upper hole on the second vertex foot. Use an M8 Washer and M8 Nut to secure it.

Reprap Prusa Mendel Frame Assembly Step 16


Step 17

Take a 450 mm Rod from step eleven and slide them through the upper frame vertices. Use an M8 Washer and M8 Nut to secure it.

Reprap Prusa Mendel Frame Assembly Step 17


Step 18

You can now attach the second frame side from step seven. Push it onto each of the roads ensuring the lower Z mounts both face outwards with the 608 bearing upwards. Secure the end of each of the threaded rods with an M8 Nut and M8 Washer. Your frame should look like the picture below.

Reprap Prusa Mendel Frame Assembly Step 18


Step 19

You can now adjust the width of the frame. Gently tighten the frame until the gap between the inside edges of the vertices is 250mm. Adjust each rod gradually tightening until all are 250mm gaps once tight your frame should be solid and sturdy on a level surface if you find your frame wobbles when on a flat surface check the spacing between vertices and ensure they are 290mm between vertices on the triangle sides and 250mm across the width. Adjust your frame in opposite corners by approximately 2 mm at a time until until your frame is solid. The lower Z mounts should still be loose and sit approximately central.

Reprap Prusa Mendel Frame Assembly Step 19


Step 20

Add a washer to each end of both 450 mm threaded bars that go through the upper vertices, then push on the Z Motor Mounts to each side. If you had to make adjustments for leveling you may find you need to add one or two extra M8 Washers between the frame vertices and Z motor mounts for them to sit flat in line with the upper frame vertices. Add an M8 Washer and M8 Nut to each rod and loosely tighten the rod clamp side, then firmly tighten the plain side. Once attached it should look like the picture below note that the clamp is loose.

Reprap Prusa Mendel Frame Assembly Step 20


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We can now proceed to 3.0 Y Axis Assembly



Prusa Mendel Parts Help and Support


3.0 Y Axis Assembly

3.1 Parts Required

Parts Required
  • 2x 400mm Smooth Rod
  • 4 x LM8UU Bearing

3.2 Assembly

Step 1

Ensure the M8 nuts holding the Rod Clamps in position are loose and then slide a 400mm Smooth Rod through from one side. Before pushing the rod into the second rod clamp slide two LM8UU Bearings on to the rod. Repeat this for both rods. It should look like the picture below.

Reprap Prusa Mendel Y Axis Assembly Step 1


Step 2

Slide the rods into the second rod clamps. Centre the rods 50mm from the inside edge of the frame vertices. Do not fully tighten yet. ensure the rod clamp has 1-2mm of play. These will be adjusted and tightened during the Y Carriage Assembly.

Reprap Prusa Mendel Y Axis Assembly Step 2
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We can now proceed to The 4.0 X & Z Axis Assembly



Prusa Mendel Parts Help and Support


4.0 X & Z Axis Assembly

4.1 Parts Required

Parts Required
  • 1 x X Motor Mount
  • 1 x X Idler End
  • 1 x X Carriage
  • 2 x Belt Clamps
  • 2 x Z Axis Springs
  • 2 x Rod Clamps
  • 2 x 300mm Smooth Rod
  • 2 x 400mm Smooth Rod
  • 2 x Rigid Aluminium Couplings
  • 7 x LM8UU Bearings
  • 8 x M3 Washer
  • 8 x M3 20mm Bolt
  • 8 x M3 Nut
  • 1 x 50mm Threaded Rod
  • 4 x M8 Nut
  • 2 x M8 Fender Washer
  • 5 x M8 Washer

4.2 Assembly

Step 1

This step may already be completed and your X Mounts will have bearings installed and secured with cable ties. If so go on to step two.

Take the X End Idler and push two LM8UU Bearings into the side recesses. Push in until the bearings locate fully in the bearing guides. Repeat this bearing installation on the X Motor Mount. Be careful not to put pressure on to the brackets on these parts.

Reprap Prusa Mendel X and Z Axis Assembly Step 1 Reprap Prusa Mendel X and Z Axis Assembly Step 1B


Step 2

Take one 300mm Threaded Rod and thread on one M8 nut approximately 100mm on from the left. Slide a Z Axis Spring on from the opposite end. Repeat this step so you have two rods.

Reprap Prusa Mendel X and Z Axis Assembly Step 2


Step 3

Take one rod push through the X end idler so that the spring is compressed inside the deep hexagonal recess on the part, then thread an M8 Nut on from the opposite end and thread on until it meets the X end idler base. Keep the spring compressed and twist the rod to locate the nut into the recess of the X End Idler. Once the lower nut is located, release the pressure on the spring and the rod should be held in place with the spring pushing out against the nuts. Twist the rod and ensure it twists through the nuts cleanly and smoothly. Repeat this with the second rod and X Motor Mount.

Reprap Prusa Mendel X and Z Axis Assembly Step 3 Reprap Prusa Mendel X and Z Axis Assembly Step 3B


Step 4

Now take two 400mm smooth rods and push in to the horizontal holes on the X end idler. Then slide two LM8UU Bearings onto the rod closest to the motor mounting point. Slide one LM8UU Bearing on to the other smooth rod. Check the picture below to ensure your bearings are on the correct rods.

Reprap Prusa Mendel X and Z Axis Assembly Step 4


Step 5

Slide the X Motor Mount onto the rods and then slide two 300mm smooth rods through the LM8UU bearings in each X end part. It should now look like the photo below.

Reprap Prusa Mendel X and Z Axis Assembly Step 5


Step 6

Take the XY axis you have made and position into the frame as in the photo below. Pass the axis through the centre of the frame. Straighten the axis and slide the threaded rods through the 608 bearings in the lower Z Mounts, now slide the smooth rods on the XY axis up into the Z Motor mount clamps. secure the top of the rods in the clamps by tightening the M8 nuts on the 450mm Threaded Rod top bars.

Reprap Prusa Mendel X and Z Axis Assembly Step 6


Step 7

Locate the bottom of the smooth rod in the cut-out on the lower Z Mount. Place an M3 Nut in each of the recesses on the lower Z mounts. secure the smooth rods using M3 20mm Bolts and M3 Washers and the two Rod Clamps.

Reprap Prusa Mendel X and Z Axis Assembly Step 7


Step 8

Take the X carriage and attach two Belt Clamps using 20 mm M8 bolts and Washers and push M8 Nuts into the recesses on the underside. Leave the belt clamps loose. Then place the X carriage onto the X axis bearings and ensure the bearings are located correctly. They should sit snug in the X carriage. Use small zip ties to secure the carriage.

Reprap Prusa Mendel X and Z Axis Assembly Step 8


Step 9

Take the 50mm threaded rod and thread on two M8 Nuts and an M8 Washer. Thread this though the hole on the X end idler. Then thread on the following parts. M8 Washer/Fender Washer/M8 Washer/608 Bearing/M8 Washer/Fender Washer/M8 Nut/M8 Nut. Tighten the M8 Nuts against each other to ensure the idler is tight and the rod does not wobble but the 608 bearing is free to spin.

Reprap Prusa Mendel X and Z Axis Assembly Step 9 Reprap Prusa Mendel X and Z Axis Assembly Step 9b


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We can now proceed to The 5.0 Y Carriage Assembly



Prusa Mendel Parts Help and Support


5.0 Y Carriage Assembly

5.1 Parts Required

Parts Required
  • 1 x Aluminum Bed
  • 4 x LM8UU Bearing Pillow
  • 2 x Belt Clamp
  • 8 x M3 10mm Bolt
  • 4 x M3 20mm Bolt
  • 12 x M3 Nut
  • 16 x M3 Washer

5.2 Assembly

Step 1

Take the four LM8UU bearing pillows and push M3 Nuts into each of the recesses. Attach the bearing pillows to the aluminum bed using 10 mm M3 Bolts and M3 Washers. On the opposite side of the aluminum bed attached two Belt Clamps using 20mm M3 Bolts and M3 Washers with M3 Nuts and M3 Washers on the underside.

Reprap Prusa Mendel Y Carriage Assembly Step 1 Reprap Prusa Mendel Y Carriage Assembly Step 1B


Step 2

Place the bed over the Y axis smooth rods. Check the below picture to ensure your bed is orientated the correct way. The belt clamps on the bed should line up with the 608 Bearings on the frame. Lineup the bearings on the Y smooth rods and carefully clip the pillows on to the bearing. Ensure you line up the bearings correctly before applying any pressure to the LM8UU bearing pillow. If you feel unsure about how much pressure is required you may find is easier to remove the Y smooth rods and slide off the 4 LM8UU Bearings. You can then install them in the pillows first. Then slide the whole bed back on and put the Y rods back in place. You can also loosen the M3 bolts holding the LM8UU Bearing Pillows to allow more adjustment. Once the bed is in place go round and gradually tighten the bar clamps holding the Y rods. While tightening slide the bed back and forward and adjust by tightening the M8 nuts against the bar clamps until they are all tight and the bed maintains a smooth action. Adding a small amount of bearing grease to the Smooth Rods can help ensure your bed runs smoothly.

Reprap Prusa Mendel Y Carriage Assembly Step 2
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We can now proceed to 6.0 – Motor – Belt – Endstop Assembly



Prusa Mendel Parts Help and Support


6.0 Stepper Motor / Belt and Endstop Assembly

6.1 Parts Required

Parts Required
  • 4 x Nema Stepper Motor
  • 2 x Aluminum Pulley
  • 2 x T5 Belt
  • 3 x Endstop Holder
  • 3 x Microswitch
  • 2 x Carbon Tube Insert
  • 6 x M2 15mm Bolt
  • 6 x M2 Nut
  • 12 x M2 Washer
  • 14 x M3 10mm
  • 17 x M3 Washer

6.2 Assembly

Step 1

Attach one aluminum pulley in to a Nema stepper motor ensuring the grub screw end is closest to the motor body the motor shaft should be flush with the pulleys edge. Tighten the grub screw against the flat side of the motor spindle. Mount the motor on to the Y motor mount using 10mm M3 Bolts.

Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 1 Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 1B


Step 2

Take another nema stepper motor and aluminum pulley and attach the pulley the opposite way round to the previous step. The grub screw end should be furtherest from the motor body. The motor shaft should be flush with the pulleys edge. Tighten the grub screw against the flat side of the motor spindle. Mount the motor on the X motor mount using 10mm M3 Bolts.

Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 2 Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 2B


Step 3

Mount two Nema stepper motors in the Z motor mounts with the shafts pointing down. Attach using four M3 10mm Bolts M3 Washers for each motor.

Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 3 Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 3B


Step 4

Attach an aluminum coupling to the top of the Z axis threaded rod and tighten the grub screw. Repeat for the second Z axis. Then lift the XZ axis assembly so that the aluminum couplings meet the Z motor shafts. Ensure the grub screws in the couplings line up with flat part of the motor shaft and once fully in position tighten the grub screws against the motor shafts. Once both couplings are in place they should support the X axis. Now level the the X axis by measuring the height from your work surface to the bottom of once of the X End plastic parts. Now hold the coupling still on that the side you measured and turn the coupling on the other side. the X Mount should move up or down, you can now adjust in the required direction until both X Mounts are the same height from your work surface.

Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 4


Step 5

Take a T5 Belt and run it around the X Idler Bearing and the X Motor pulley. Bring the ends together under the belt clamps on the X carriage. Pull the ends through until the belt is tight but does not strain the X idler mount. Tighten the M3 Bolts in the X Carriage to hold the belt in place.

Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 5


Step 6

Take the second T5 Belt and run around the 608 Bearings and the Y motor pulley, place the ends under the belt clamps on the aluminum bed and tighten the M3 bolts just enough to hold the belt still. now adjust the M8 Nuts either side of the 608 Bearings on the frame and move until the belt, bearings and pulleys all run in a straight line, gradually tighten the M8 Nuts, the Belt Clamps and the Y motor Mount while sliding the bed back and forward and ensure the belt runs straight, the bed should move smoothly, however you may feel some resistance from the stepper motors. Only a small amount of force should be needed to move the bed and it should not have a jerky motion. Once you are happy gradually tighten the Nuts and tighten the belt clamps down.

Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 6 Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 6 B


Step 7

Take a microswitch and attach it to an Endstop Holder using 20mm M2 Bolts with an M2 Washer on each side and an M2 Nut.

Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 7


Step 8

Using 20mm M3 Bolts with a washer and an M3 Nut placed in the End Stop Holder recess, attach the first Endstop assembly to the Z Axis Smooth Rod underneath the X Idler. It should be positioned so the microswitch is depressed when the X Idler comes down the Z axis and hits the microswitch, before hitting the print bed. Loosely attach and this will be adjusted when the print bed is assembled. Place the second of the Endstop assemblies on the X Axis smooth rod where is will be activated when the X Carriage returns along the X axis. Place the third assembly on the Y axis smooth rod to the right of the Y Motor, this will be activated by the aluminum bed.

Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 8 Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 8B Reprap Prusa Mendel Stepper Motor Belt & Endstop Assembly Step 8C


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We can now proceed to 7.0 Build Bed & Heated Bed Assembly



Prusa Mendel Parts Help and Support


7.0 Build Bed & Heated Bed Assembly

7.1 Parts Required

Parts Required
  • 1 x Wooden Bed
  • 4 x Bed Springs
  • 4 x M4 Countersunk Bolts
  • 1 x Bed Thermistor
  • 1 x Heated Bed
  • 1 x Aluminium Tape
  • 4 x M4 Nut
  • 12 x M4 Washer
  • 6 x Bulldog Clip

7.2 Assembly

Step 1

Lay the Wooden Bed with the countersunk holes face down and the cut out at the bottom. Using the Aluminum Tape attach the Bed Thermistor to the Wooden Bed. The thermistor should poke through the central hole on the bed about 1mm. Tape this securely and run the cable to the right.

Reprap Prusa Mendel Build Bed & Heated Bed Assembly Step 1


Step 2

Place the wooden bed over the Aluminum Bed on your printer. The Aluminum tape should be facing down and the cut out in the Wooden Bed should be at the front of the frame (The Y Motor Is the rear of the frame). Secure this in place using the M4 Countersunk Bolts. Thread the bolt through the Wooden Bed, Then thread on an M4 Washer, Bed Spring and M4 Washer, thread through the Aluminum Bed and add an M4 Washer and M4 Nut. Repeat this in each corner and then tighten down so that the springs compress to 2/3rds of the original length. Measure the gap between the wooden bed and aluminium bed in one sprung corner and then adjust the other corners to the same height. You can also use a small spirit level to ensure the bed is as level as possible. Place the spirit level on each side of the wooden bedand adjust the sprung bolts to get an even level at each edge. Then place the spirit level diagonally across the bed to and adjust the sprung bolts if necessary.

Reprap Prusa Mendel Build Bed & Heated Bed Assembly Step 2 Reprap Prusa Mendel Build Bed & Heated Bed Assembly Step 2B Reprap Prusa Mendel Build Bed & Heated Bed Assembly Step 2C


Step 3

Place the Heated Bed on the Wooden bed, thread the cables under the wooden bed and follow the thermistor cables out the left hand side. Position the centre of the Heated Bed over the thermistor in the centre of the wooden bed.

Reprap Prusa Mendel Build Bed & Heated Bed Assembly Step 3


Step 4

Now take the Mirror Build Plate top and some kapton tape ( 20mm Wide supplied with kit) and carefully cover the mirror in kapton tape. This is a bit like putting a screen protector on a mobile phone, use a card or something similar to evenly spread the kapton tape over the mirror ( try to avoid overlapping the kapton tape, as the hot end could foul on the marginal change in height and try and avoid air bubbles for the same reason). If you do get any air bubbles trapped, use a sharp knife or pin and prick the bubble slightly and you should be able to squeeze any air out.

Reprap Prusa Mendel Build Bed & Heated Bed Assembly Step 3 Reprap Prusa Mendel Build Bed & Heated Bed Assembly Step 3


Step 5

Now place the mirror over the heated bed and clamp it onto the heatbed & plywood build base using the 6 bull dog clips provided. Then remove the silver spring arms from the bull dog clips. You can just use 4 on the front and back if you wish. With the two bull dog clips on the side make sure they are positioned so that they don’t foul the hot end and also don’t fowl the sides of the frame (angled rods).

Reprap Prusa Mendel Build Bed & Heated Bed Assembly Step 3 Reprap Prusa Mendel Build Bed & Heated Bed Assembly Step 3 Reprap Prusa Mendel Build Bed & Heated Bed Assembly Step 3
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We can now proceed to 8.0 Extruder Assembly & Hot End Connection



Prusa Mendel Parts Help and Support


8.0 Extruder Assembly & Hot End Connection

8.1 Parts Required

Parts Required
  • 1 x Hot End End
  • 1 x Extruder
  • 1 x Extruder Idler
  • 1 x Extruder Large Gear
  • 1 x Extruder Small Gear
  • 1 x Hot End Clamp
  • 1 x Hobbed Bolt
  • 4 x M8 Washer
  • 1 x M8 Nylock Nut
  • 3 x 608 Bearing
  • 1 x 16mm Smooth Rod
  • 2 x M3 40mm Bolt
  • 2 x M3 Nylock Nut
  • 4 x M3 Washer
  • 2 x M4 50mm Bolt
  • 4 x M4 Nut
  • 6 x M4 Washer
  • 2 x Extruder Spring
  • 1 x Nema Stepper Motor
  • 1 x M3 Grub Screw
  • 1 x M3 Nut
  • 3 x M3 10mm Bolt

8.2 Assembly

Step 1

Take the 16mm Smooth Rod and slide through a 608 Bearing. Place this into the Extruder idler. Push in until the Smooth Rod is fully located. Using a 40mm M3 Bolt with M3 washer and M3 Nylock Nut attach the idler to the Extruder.

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 1


Step 2

Push a 608 Bearing in to the recess on the flat side of the extruder. Take the Hobbed Bolt and slide on the Extruder large gear. Then Thread on 4 M8 Washers, one 608 Bearing and 1 M8 Washer. Slide the hobbed bolt through the Extruder and through the 608 Bearing. Add 2 M8 Washers and an M8 Nylock Nut and tighten together until there is no wobble on the Hobbed Bolt but the Extruder Large Gear turns freely.

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 2


Step 3

Push 2 M4 Nuts in to the recesses on the top of the Extruder and pull up the the idler. Take two 40mm M4 Bolts and thread on each an M4 Washer, Idler Spring and M4 Washer. Push through the idler and screw into the M4 bolts in the recesses. Ensure the bolts screw in and compress the springs then loosen the bolts back off.

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 3


Step 4

Take the Extrude Small Gear and push an M3 Nut in to the recess, secure the nut using an M3 Grub Screw. Take a Nema Stepper Motor and Line up the grub screw with the flat part of the motor shaft and push the gear onto the shaft. The Motor shaft should be flush with the edge of the gear. Tighten the grub screw.

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 4


Step 5

Attached the motor to the Extruder using three 10mm M3 Bolts. when in position loosen the bolts a little and push the motor in so the gears fit as tightly as possible against the Large Gear. Then tighten the motor in place.

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 5


Step 6

Take the Hot End Clamp and push a M3 Nylock nut in to the recess on the side. Secure with a 40mm M3 Bolt and M3 Washer. The clamp can be very tight, this is to ensure the hot end stays in place. You may find it useful to use a longer M3 bolt. There will be one in the spare parts bag. Leave the clamp loose.

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 6

Push two 50mm Hex Top Bolts through the base of the extruder so the heads locate in the recesses. Slide the Hot end clamp on to the Hex Top Bolts. Ensure that the clamp opening is on the same side as the extruder gear. The clamp only fits on to the X Carriage one way so if it is the incorrect way round, your Extruder will be mounted backwards.

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 6 B


Step 7

Take your Hotend part and inspect it carefully before using. Check that the barrel is not loose and there are no gaps between components. There are two resistors running through the aluminum block, check there are no breaks on the connections. There is a smaller thermistor also in the top of the aluminum block. the glass bead on this should be inside the block. If it is protruding from the block or has slipped out completely, use a pair of tweezers and gently push it in to the aluminum block. Hold the Brass tip up to a light and look through the Hotend, Make sure you can see the pin hole and ensure there is no debris inside. Make sure the PTFE lining is pushed in fully and flush with the top of the Hotend.

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 7


Step 8

Take your Hotend Part and remove the white PTFE Disc. Push this in to the 16mm round recess on the bottom of the extruder. This disc acts as a barrier stopping the inner PTFE lining of the Hotend from being pulled out when the extruder reverses. Push it all the way through the clamp and in to the Extruder recess, ensure it is all the way in and flat.

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 8 Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 8


Step 9

Take your Hot end and push in to the recess to butt up against the PTFE Disc. The Hotend must be pushed all the way in to the extruder. Do not leave any gap between the extruder, PTFE Disc and Hotend. Once in place, ensure the Hotend Clamp is pushed all the way up to the extruder and tighten the clamp around the Hotend.

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 9 Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 9


Step 10

Now take your Extruder/Hotend assembly and feed the Hotend cables down through the centre of the X Carriage part. The Gears on the extruder should face the front of the printer. The rear of the printer (the rear has the Y Motor Mount).

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 10 Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 10


Step 11

Once the cables are through line up the Hex Bots with the X Carriage and guide the whole assembly down.

Reprap Prusa Mendel Extruder Assembly & Hot End Connection Step 11


Step 12

Connect the other end on the Power Supply cables to the cables on your main power supply. The smaller connector has only one matching connector on the main power supply. The wider connector will atatch to any of the matching connectors on the main power supply.

Reprap Prusa Mendel Electronics Wiring & Connections Step 12


Step 13

Connect Power Supply cable to the green socket.

Reprap Prusa Mendel Electronics Wiring & Connections Step 13


Step 14

CWe have supplied a generic electronics enclosure (RAMPS Box). This isn’t specifically designed the Ramps board, so feel free to cut and modify the box in order to locate the electronics how you wish, a small hacksaw, or sharp knife should be suitable for cutting the box. We have done this as there are many ways of locating the electronics on or around the printer and we felt this should be up to you.

Please note however don’t put the cover on the box unless you are providing additional cooling ( fans etc) otherwise the RAMPS board won’t receive enough ventilation. All of our machines run without fan cooling, but the tops of the RAMPS Boards are left exposed, hence we don’t supply a fan.

Also we wouldn’t recommend making any of the wiring runs/routing permanent, until you have completed section 11.0 Commissioning and have completed your test prints and are sure everything is 100% connected correctly and working.

Reprap Prusa Mendel Electronics Wiring & Connections Step 14 Reprap Prusa Mendel Electronics Wiring & Connections Step 14

If you want to cover the box, you will need to implement additional cooling as the convection cooling effect without the lid on will no longer occur with the lid on. Some Examples You could connect a PC Case fan to one of the spare 5v molex connectors on the Power supply for a permanently running fan. You could mount pc headers onto one of the RAMPS Boards AUX Mounts and then control the fan using the host software.



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We can now proceed to 9.0 Wiring & Connections



Prusa Mendel Parts Help and Support


9.0 Wiring – Reprap Prusa Mendel Build Manual

9.1 Parts Required

Parts Required
  • Assembled RAMPS 1.4 Board
  • Stepper Motor Crimps and Connectors

9.2 Completing Connections

Everything has been pre connected and soldered other than the stepper motors which need to be crimped. (no soldering)

9.3 RAMPS 14 Board Diagram



9.4 Making Connections

You can now connect your printer to the RAMPS Hardware. Your RAMPS board already has two cables connected, these are for the Hotend thermistor and power, the ends are labeled. You should place your ramps board the to rear left hand side of your printer. Run the Hotend cables over the printer and drop through the upper threaded rods Connect these to your Hotend. As you connect your components to the ramps board use cable ties to hold the cables against the frame and ensure no cables are trapped or touching moving parts.

We recommend loosely tidying cables until your printer is fully running and then making permanent later. Make sure when connecting plastic connectors, that the pins are fully inserted in to the plastic plugs, but have not pushed the connector out of the plug housing.

Step 1

Start by connecting the Heated Bed power cable to the screw terminals labelled D8 on the Ramps Board.

Reprap Prusa Mendel Electronics Wiring & Connections Step 1


Step 2

Connect the Heated Bed Thermistor to connector labelled T1.

Reprap Prusa Mendel Electronics Wiring & Connections Step 2


Step 3

Connect the X Endstop Microswitch to the connector labelled x. Ensure the black cable is closest to the centre of the RAMPS board.

Reprap Prusa Mendel Electronics Wiring & Connections Step 3


Step 4

Connect the Y Endstop Microswitch to the connector labelled y. Ensure the black cable is closest to the centre of the RAMPS board.

Reprap Prusa Mendel Electronics Wiring & Connections Step 4


Step 5

Connect the Z Endstop Microswitch to the connector labelled z. Ensure the black cable is closest to the centre of the RAMPS board.

Reprap Prusa Mendel Electronics Wiring & Connections Step 5


Step 6

Connect the X Motor to the connector labelled X. Ensure the Red cable is closest to the green screw terminals on the RAMPS board.

Reprap Prusa Mendel Electronics Wiring & Connections Step 6


Step 7

Connect the Y Motor to the connector labelled Z. Ensure the Red cable is closest to the green screw terminals on the RAMPS board.

Reprap Prusa Mendel Electronics Wiring & Connections Step 7


Step 8

Connect the first Z Motor to the lower connector labelled Z. Ensure the Red cable is closest to the green screw terminals on the RAMPS board.

Reprap Prusa Mendel Electronics Wiring & Connections Step 8


Step 9

Connect the second Z Motor to the upper connector labelled Z. Ensure the Red cable is closest to the green screw terminals on the RAMPS board.

Reprap Prusa Mendel Electronics Wiring & Connections Step 9


Step 10

Connect the Extruder Motor to the connector labelled E0. Ensure the Red cable is closest to the green screw terminals on the RAMPS board.

Reprap Prusa Mendel Electronics Wiring & Connections Step 10


Step 11

Connect Power Supply cable to the green socket.

Reprap Prusa Mendel Electronics Wiring & Connections Step 11


Step 12

Connect the other end on the Power Supply cables to the cables on your main power supply. The smaller connector has only one matching connector on the main power supply. The wider connector will atatch to any of the matching connectors on the main power supply.

Reprap Prusa Mendel Electronics Wiring & Connections Step 12


Step 13

Connect Power Supply cable to the green socket.

Reprap Prusa Mendel Electronics Wiring & Connections Step 13


Step 14

We have supplied a generic electronics enclosure (RAMPS Box). This isn’t specifically designed the Ramps board, so feel free to cut and modify the box in order to locate the electronics how you wish, a small hacksaw, or sharp knife should be suitable for cutting the box. We have done this as there are many ways of locating the electronics on or around the printer and we felt this should be up to you.

Please note however don’t put the cover on the box unless you are providing additional cooling ( fans etc) otherwise the RAMPS board won’t receive enough ventilation. All of our machines run without fan cooling, but the tops of the RAMPS Boards are left exposed, hence we don’t supply a fan.

Also we wouldn’t recommend making any of the wiring runs/routing permanent, until you have completed section 11.0 Commissioning and have completed your test prints and are sure everything is 100% connected correctly and working.

Reprap Prusa Mendel Electronics Wiring & Connections Step 14 Reprap Prusa Mendel Electronics Wiring & Connections Step 14

If you want to cover the box, you will need to implement additional cooling as the convection cooling effect without the lid on will no longer occur with the lid on. Some Examples You could connect a PC Case fan to one of the spare 5v molex connectors on the Power supply for a permanently running fan. You could mount pc headers onto one of the RAMPS Boards AUX Mounts and then control the fan using the host software.



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We can now proceed to 10.0 Reprap Prusa Mendel Computer Setup



Prusa Mendel Parts Help and Support


10.0 Reprap Computer Setup

10.1 Reprap 3D Printer Connecting Hardware

Reprap Prusa Mendel Computer setup

10.1.1 Hardware Setup & Connection.

Parts Required

  • 0.3 Software CD ( or from the 3D Printer Software Downloads page).
  • 1.1 Fully Assembled RAMPS
  • 1.2 Ramps Power Cables
  • 1.4 550W Silent ATX Power Supply
  • 1.5 ATX Power Supply Adaptor
  • 1.9 Mains Power Lead & USB 2.0 Cable

Setting Extrude Lenght in Pronterface

Ensure your computer is in good working order and you have a free USB 2.0 port and a mains power socket within reach.

Boot up your computer and either insert the software CD that came with your Prusa Mendel 3D Printer Kit or navigate to 3D Printer Software Downloads . Create a folder called “REPRAP” wherever you want to work/run your 3D Printer from and then either Download Ver 1.0 (MUST BE THIS VERSION) of the Ardunio Dev Environment or copy from the CD the Folder called “ARDUINO 1.0” and place inside the newly created “REPRAP” folder.

Connect the green connector from the RAMPS Power Leads(1.2) to the green connector on the RAMPS board.

Now connect the 4 Pin Square connector on the RAMPS Power Cables(1.2) onto the the lone P4 Power connector on the ATX Power Supply(1.4) and connect the rectangular connector on the RAMPS Power Cables(1.2) onto one of the rectangular power connectors on the ATX Power Supply(1.4)

Now connect the ATX Power Supply Connector(1.5) onto the the 20Way ATX connector on the ATX Power Supply(1.4).

Now connect the Mains Power Lead(1.9) to the ATX Power Supply(1.4) and the other end to a spare mains socket.

Now connect the USB Cable(1.9) to the RAMPS Board(1.1) and connect the other end to the spare USB2.0 port on the computer. – You may notice a green light or two flash on the RAMPS Board.

Now switch the power switch on the back of the ATX Power Supply(1.4) to the on position. – The fan on the Power Supply should start to spin.

Now proceed to 10.1 Arduino Driver Installation

Prusa Mendel Parts Help and Support


11.0 Commissioning & Calibration

11.0 Commissioning the Reprap Prusa Mendel 3D Printer – Prusa Mendel Build Manual

These sections will take you through the final steps in setting up your printer and printing your first prints. Some areas of the commissioning will be related to your computer set up We recommend you read through both the computer set up sections and commissioning sections before starting either. These sections include instructions for setting up important parts of your printer and both should be carried out at the same time.

11.1 Frame Levelling



Step 1

It is important that your printer is kept level. After you have used your printer you should regularly check that it is level and the frame nuts are tight. This is especially important any time that you change or adjust any other hardware on your printer, such as your bed or a hot end.

Check that the surface your printer will be used on is level. Position your printer where it will be used. Remember to allow enough room for the bed to move fully and allow you some access to all sides. Leave space for your electronics and the Power supply. The build instructions suggest your RAMPS board is located to the rear left of the printer, however the cables are long enough for your to position things to suit your workspace. It can be useful to have good access to the main power supply on/off switch as this can act as a master cut off for your printer should you need to stop it quickly, this is not a recommended way to stop your printer though.

Now check that all nuts on your printer frame are tight. The printer should sit squarely and not twist. Don’t over tighten the plastics as they can crack. Regularly check your nuts are tight. Vibration from printing can loosen them over time. Keeping them tight can also reduce wear from them moving or rattling. It will reduce undue stress to plastic parts.

Frame Leveliing Step 1


Step 2

Take a small spirit level (A weighted piece of string will also work if you do not have a small spirit level) and hold it against one the smooth rods on the outside on the Z Axis. Loosen the M8 nuts next to the lower Z axis and move the axis until your Z Axis is level then tighten. Repeat this for both of the Z Axis. This ensures the Z axis moves up and down straight. Check this regularly. Its a good idea to check and tighten the couplings on the Z threaded rods and Z motors at the same time as adjustment on these will pull the z axis out of line.

Frame Leveliing Step 2


Step 3

Now measure then gap between your work surface and the base of the X End Motor Mount. Make a note of this and then hold the coupling tight on that Z Axis. Twist the opposing Z Axis coupling to raise or lower your X Idler Mount until it is the same height as the other X end. Check this regularly. If you find that when printing this is not staying level. This could be caused either by the couplings slipping or the stepper motors skipping steps. If the a stepper is missing steps (ie not turning when it should) refer to section “11.4 Adjusting Stepper Motor Drivers” and check the calibration of the Z Motor stepper driver. Note this shouldn’t be necessary as they have already been calibrated and performed a test print.

You can use this adjustment to fine tune your bed leveling. If you have a spirit level you can use it to ensure your X Axis is perfectly level by placing it across the ZX Axis smooth rods. Turn the Couplings until it’s level.

Frame Leveliing Step 3

Now proceed to 11.2 Bed Levelling



11.2 Bed Levelling



Step 1

Check that all four corners of your bed have the springs securely in place. Measure the height from your work surface to the wooden bed in one corner. Adjust the corner screws until all four corners are the same height.

Bed Leveliing Step 1


Step 2

If you have a spirit level you can use it to ensure your bed is perfectly level. Place it on each edge of the bed and adjust the bed screws to level.

Bed Leveliing Step 2


Step 3

If you are using a Heated bed plate We recommend you level your bed at each stage. You should level the wooden bed, then add your heated bed and use your bulldog clips to hold in place then check the level of your bed again and adjust it if needed. Additionally if you use one of our mirror beds or another glass layer we recommend you use bulldog clips to clamp the mirror and heated bed down and then check the level of the bed.

Bed Leveliing Step 3


Step 4

Now bring your Z axis down until the tip of the Hotend is approximately 10mm from the bed. If you have set up your computer you can use the software to lower the Axis. Be careful not to go too far as you risk damaging the Hotend nib against your bed. If you have not set the computer you can twist the couplings at the same time to bring both sides of the X Axis down. Once you have lowered the Axis Check it is still level and adjust it if needed.

Bed Leveliing Step 5


Step 5

If your computer is set up, turn off the motors. If you are not connected make sure your X Carriage and Bed are both free to move. Now while watching your Hotend nib move the bed back and forward. Watch to see if the gaps between your bed and the Hotend stays consitent. If you see that the gap changes, adjust the bed corners to bring it level. Do the same with the X Axis. Move the X Carriage side to side and watch the Hotend tip. Adjust the X Axis by truning the Z Axis couplings while holding the other still. This will raise or lower the end.

Bed Leveliing Step 5


Step 6

Repeat these steps while gradually lowering the X Axis down the Z Axis. Ensure the Hotend stays level above the bed until it is 1-2mm from the bed. Now slide a piece of paper between the nozzle tip and your bed. This will prevent your hot end from scratching your print surface while adjusting the Endstops.

Bed Leveliing Step 6

Now proceed to 11.3 Endstops

11.3 Endstops

The Endstops are used by your printer to know where so start and stopped. they are triggered when the metal pin on the microswitch is pressed, the motor on the coresponding axis will stop (reached home).

Step 1

The Z Axis end stop should be pushed up against the base of the X end so that the pin is depressed. Your Hotend should be close to the right height following the previous steps. Now using the software raise your Z axis up by 10-20 mm. Then lower your Z Axis by the smallest increments, position the end stop so the switch is pressed before the Hotend nozzle touches the bed surface. The correct gap between bed and nozzle tip is around .35mm Using the piece of paper you left between the nozzle tip and bed, lower the Z Axis until the nozzle is a close as possible but you can still move the paper. When your Endstop is at the right height tighten the clamp. Now move your hotend around on the x axis and check that the gap between your hotend and bed is the same across the bed. Check next with he Y axis by moving them bed. follow the bed leveling and frame leveling steps to make any adjustments.

Endstops Commissioning Step 1


Step 2

To get the X axis Endstop in the correct position, check that when the X Carriage moves along the rods, part of the extruder body should make contact with the switch. when the X Carriage is all the way across and the switch is depressed check that the Hotend nozzle tip is above the bed still and if it has gone past and will not catch on your bulldog clips. You can bring the Endstop in along the rod to adjust.

Endstops Commissioning Step 2


Step 3

Ensure the Y Endstop is in position to be activated by the Aluminum bed when it returns along its axis. Check that your bulldog clips and cables do not catch on it. Check from above that when in position the hotend does not run off the bed or hit a bulldog clip. Adjust it along the rod if required.

Endstops Commissioning Step 3


Step 4

With your Endstops in place and your frame and bed level ensure your computer software is set up and test the movement of your printer (as per section 10 Computer Setup. Make sure that your Axis move in the correct direction and check there is no excess strain on belts or pulleys. Check for any loose nuts and bolts.

Endstops Commissioning Step 3


Now proceed to 11.4 Pololu Stepper Driver Calibration

11.4 Adjusting Stepper Motor Drivers


Step 1
The Pololu A4988 Stepper Drivers have already been assembled, calibrated and mounted to your RAMPS Board. But it may be necessary to adjust them slightly if you are experiencing certain issues, such as missing steps ( when the print staggers in an Axial direction) or if you are experiencing extrusion consistency issues). Either way the following is for your reference to help you understand how the stepper drivers affect the printer.

We use low voltage Nema 17 Stepper Motors which can take a maximum current of 1.68A at a 2.8V the Polulo A4988 Stepper Driver can drive up to 2A, this is far higher than the level required, resulting in the stepper motors running a lot cooler.

There is a very fine line between too much current and too little current in relation to the accurate operation of the stepper motor itself.

The best starting point is about 0.7x the rated current, this is the maximum current the stepper driver can output before requiring a heat sink ( n.b Heatsinks are already fitted).

You can calculate the approximate required Vref Voltage value by applying the following calculations :

Vref = Stepper Motor Max Current x Factor Current x 0.4
Vref = 1.85A X 0.7A x 0.4 = 0.47V
So now select DC Current on your Multimeter to two decimal places.

calibrating pololu stepper drivers


Step 2

With power connected and on and the stepper motors connected, locate the Vref Adjustment Pot and looking at the stepper driver in the following orientation the 2nd pin in from the left along the top row and measure the current by putting the ground probe on the 2nd pin from the left on the top row and the positive probe on the adjustment pot, poke the probe into the pot until you get a reading on your multimeter. Make sure you don’t slip and touch any of the other pins as this could damage the stepper driver.

calibrating pololu stepper drivers Step 2 calibrating pololu stepper drivers Step 2a


Step 3

Now we have a reading of the Vref voltage, it should be between 0.40 and 0.50v, if we wish to adjust it we need to turn the pot slightly, if we turn it clockwise we’ll increase the current drawn and anti clockwise we’ll reduce it. Use an insulated small slotted screwdriver to turn the pot slightly. There is a flat side to the pot, usually this should sit at around the 10/11 O’Clock position.

calibrating pololu stepper drivers Step 3


Step 4

Now you have adjusted the pot slightly re-read the Vref voltage as in step 2 and you should see the change in the Vref from the adjustment you made, now you should have a feel for the amount of change in Vref in relation to the degree change of the pot. A value of between 0.4v and 0.5v is appropriate for the Stepper Motors in you kit.

You should notice a physical change in the behaviour of the stepper motor as the Vref is manipulated, when it is too low the stepper motor will make a noise and vibrate as if it were moving but it will fail to move or move accuratley, if the Vref and hence current is too high the stepper motor will move in jerky overly highly torquey manner ( it will seem unnecessarily powerful for the printer) and after a certain point the motor won’t move again and will vibrate and get very hot.

Depending upon which motors are being used more heavily when printing will depict how warm/hot they get along with their respective heat sinks on the stepper drivers, so for example the Extruder stepper may well be considerably hotter than the z axis stepper motor as it is doing considerably more work




Now proceed to 11.5 Hot End

11.5 Hot End

In the Pronterface software check the figure in the Heater dialog box. Make this 230 if not already. Click “Set” in the next box. You can now click “Check temp”. Pronterface will show you a reading. You Hotend should get to 230 in a couple of minutes. The check box at the top in Pronterface labelled “Monitor Printer” will start Pronterface regular temperature checks and the latest temperature for Hotend and Bed will be displayed.

Commissioing Hot End
See also Hot End Maintenance For more on removing and installing your hot end.
Now proceed to 11.6 Heated Bed

11.6 Heated Bed

You can now turn on the heated bed. In the Pronterface software check your bed temp is 110 in the dialog box and click “Set”. The Bed is much slower to heat than the Hotend. Also any further layers on your heated bed will take longer to heat. If you are using a mirror or glass bed leave your bed heating for a further 10 minutes after Pronterface shows the temp has reached 110.

Commissioing Heated Bed

Now proceed to 11.7 Loading Filament

11.7 Loading Filament

Step 1

To load filament for the first time, start by ensuring your Hotend is at the correct temperature (230 for ABS). Ensure your motors are set to off in the Pronterface software. Remove the two sprung bolts from the Extruder Idler and pull the Idler down.

Loading Filament Prusa Mendel commissioning Step 1


Step 2

Take the end of your filament and ensure is has no kinks or twists in it. Take the end of your filament and using wire cutters or a stanley knife cut diagonally across the filament. This creates a pointed end to ease feed to filament on to your Hotend.

Loading Filament Prusa Mendel commissioning Step 2


Step 3

Feed the filament between the top threaded rods of the printer. Feed it down through the hole in the top of the extruder. When is gets to the hobbed bolt the filament will be pushed away from the lower hole. Use small pliers to push the filament down throught the lower hole. Once in turn the large gear on the extruder to feed the filament through.

Loading Filament Prusa Mendel commissionin Step 3 Loading Filament Prusa Mendel commissionin Step 3a Loading Filament Prusa Mendel commissionin Step 3b


Step 4

Keep feeding the filament until it reaches the bottom of the Hotend, you should see the filament start to ooze from the Hotend. If your filament stops moving before you see any released from the hotend first check your temperature and make sure your hotend is at 230. If it has cooled, get back to temperature before trying to remove or reload the filament. When hot reverse the direction of the extruder gear and pull the filament up and out. Always check that your hot end has not moved or been pushed out of the hotend clamp. trim back the filament and create a new sharp end with a knife. Re feed it in to the extruder.

The filament can have a curve from the reels, twisting the filament and feeding again can help when your filament is stopping before entering the hotend. If you it remains hard to feed filament through to the hot end and you are sure there is not debris or blockage in the extruder or hotend then another method is to hold your hotend with a pair of large pliers and loosen the hotend clamp. slide the hot end out. Then feed the filament down through the extruder and holing the hotend line up the filament from the bottom of the extruder and push the hotend up into place. Tighten the hot end clamp back up. Also make sure to check your Z endstop home position.

Loading Filament Prusa Mendel commissioning Step 4


Step 5

Now pull the Idler back up and put the two sprung bolts back in. Tighten the bolts so the bearing in the idler pushes the filament against the Hobbed bolt. Tighten them so that the springs compress to approximately 80% of their original length.

Loading Filament Prusa Mendel commissioning Step 5


Step 6

Now you can test extruding filament from the Pronterface software. Use Pronterface to move your axis so that the Hotend tip is approximately 50mm from the bed. In Pronterface check that the Extrude length is 5mm and click “Extrude”. You should see filament come out of your Hotend. Now increase the extrude length in pronterface to 50mm and click “extrude”. Watch the filament as is releases. You should see a consistent line extruded at a consistent speed. If your filament is extruding fast then slow or it is coming out at different thicknesses, adjust the tension on the two sprung extruder bolts. Tightening them will push the filament against the hobbed bolt increasing grip. If these are too tight the filament will grind against the hobbed bolt and not extrude.

Loading Filament Prusa Mendel commissioning Step 6

Now proceed to 11.8 Removing Filament

11.8 Removing Filament

Step 1

Always ensure you Hotend is up to temperature before removing filament (230 for ABS). Turn off the motors in the Pronterface software (Button Located on the top left hand side). Then remove the two Sprung bolts in the extruder idler.

Removing Filament Prusa Mendel commissioning Step 1


Step 2

Grip the filament above the extruder and pull up in one swift movement. This ensures the filament comes out cleanly and no blobs of plastic are left behind. You may find it helpful to turn the large gear on the extruder in reverse as you pull the filament up.

Removing Filament Prusa Mendel commissioning Step 2


Step 3

Whenever removing filament, always check your Hotend is fully located in the extruder recess before reloading. If necessary you can loosen the Hotend clamp an holding the Hotend with pliers or grips push up into position and retighten the Hotend Clamp.

Removing Filament Prusa Mendel commissioning Step 2


11.9 Changing Hot Ends

When changing a hot end always remove the filament before starting and always remove when the hot end is at full temperature (230°C. (Refer to 11.7).

We recommend allowing your hotend to cool before changing.

Loosen the hotend clamp and grip the hotend with large pliers around the aluminium heater block.

Removing Hot End Prusa Mendel commissioning Step 1 Removing Hot End Prusa Mendel commissioning Step 2 Removing Hot End Prusa Mendel commissioning Step 3 Removing Hot End Prusa Mendel commissioning Step 4

Take care not to crush the thermistor and resistor cables. Slide the hotend down and out of the extruder and through the hotend clamp. Then disconnect the cables.

When changing a hot end always check that the PTFE disc stays in place in the extruder recess.

Always check for debris in the extruder and hotend. If your hotend will remain out of your printer for some time place a strip of kapton tape over the hole and ensure the brass nib does not get damaged.

Refit or install your replacement by sliding through the hotend clamp and in to the extruder recess. Ensure it is all the way in and tighten the hot end clamp. Always check the Z endstop home position after changing hotends.
See also Hot End Maintenance For more on removing and installing your hot end.

11.10 Printing a Test Print


Assuming you have worked though section 10.0 Computer setup and installed all the required software & drivers, you are now ready to complete your 1st test print.

The printer should be powered up and connected to the computer (as in section 10.0) and Filament loaded into the extruder and hot end (Section 11.6)

Now open Pronterface ( by clicking on the pronterface.py shortcut that we created in section 10.0). Now connect to the printer and set the temperature of hot end (heater) and the heat bed and wait a few minutes whilst the printer gets up to temperature.

Now we need to generate some Gcode from an STL 3D Design file. The Gcode is the list of commands that is directly transmitted to the printer. In order to generate the G Code we need to use the “compose” function of Pronterface, this creates a graphical representation of your print bed, allows you to position the object on the heat bed and then pronterface generates the Gcode by using Skeinforge (Pronterface acts as a front end for Skeinforge).

Click compose and the following window will appear, then select load and navigate to your Reprap folder and the “STLs” folder inside the folder you should find a file called 20mm-box.stl, select this file and open.
Printing a Test Print - Prusa Mendel commissioning Step 1 Printing a Test Print - Prusa Mendel commissioning Step 2

Now you should have a green graphical representation of the object to be printed in the bottom left of the window. Click and hold on the object and drag it into the centre of the build area, note you can also rotate the object by holding down “alt” and scrolling.

Printing a Test Print -  Prusa Mendel commissioning Step 3

Now select done and the compose window will close and the pronterface dialogue will start showing a log of the G Code as it is being generated, depending upon how fast your computer is and the size and complexity of the object will affect the time taken to generate the G Code. On a relatively modern dual core machine it should take less than a minute or so to generate the code for the test cube, the log will indicate once it’s complete and an image should appear in the central window.

Printing a Test Print -  Prusa Mendel commissioning Step 4 Printing a Test Print -  Prusa Mendel commissioning Step 5

The Gcode that is generated is stored in a folder called “Temp STL” inside the Printrun/Pronterface application folder. If you want to keep the gcode you generated to save generating it again in the future, copy the generated g code file and store it somewhere else, then you can just select file open and open the Gcode file directly within pronterface.

Now ensure the printer is up to temperature by selecting check temp and or ticking the monitor printer box, once the hot end is up to 230°C and the heat bed is over 100°C you are ready to print. Assuming you have completed the bed leveling section earlier in this chapter, click the home all axis button the white button with a home symbol in the bottom left of the axis control button area.

The printer should now move all of the axis to their respective home positions, now you can press the print button.

Printing a Test Print -  Prusa Mendel commissioning Step 6 Printing a Test Print -  Prusa Mendel commissioning Step 7

Once you have pressed print watch your printer lay down the first lines of plastic. Your plastic extrusion should come out smoothly and adhere to your print surface. Watch as the printer turns corners. Make sure the plastic sticks to the bed and doesn’t pull off. common causes are that the bed is not hot enough or the z axis endstop is to high. If your plastic is being squashed down against your bed by the hotend nib your Z axis endstop may be too low and you risk damaging the bed. This is when having your power supply main switch close can help avoid accidentally scraping the hotend nib on the bed. If your hotend does scrape your bed or hit a bulldog clip you should always check and reseat the hotend.

Watch as your printer builds the first layer. If the lines judder, check your bed and X axis movement. Check they both move smoothly. Add some bearing grease or a small dab of oil to the smooth rods to help the bearings. You should regularly twist the rods to avoid constant bearing wear. Then check the tension of the X and Y belts. They should have some flex but you should not be able to slip the teeth around the motor gear.

Your plastic should come out in smooth lines and consistent speeds. If it is not lift the Z axis and extrude 50mm through the hotend. Check whether it is consistent. Adjust the sprung bolts on the extruder and check by extruding again. If it remains inconsistent check your stepper motor drivers and check the teeth on your cogs. If your prints remain inconsistent but when tested straight through he extruder it is fine, you should check your skienforge settings.


Printing a Test Print -  Prusa Mendel commissioning Step 8

If the printer is not adhering or the layers are not in line you can pause your printer from pronterface. Raise the Z axis to move the hotend away and remove the misprint. Once you’ve resolved the cause you can reprint from pronterface. Always move your hotend to the home position before restarting your print.

When the cube is complete the hotend will move away. The bed and hotend will turn off and begin to cool. You should allow the print to cool before removing from the bed. Be careful not to damage the heated bed when removing prints.

Move your hotend to its home position and set the heated bed and hotend temperature and you are ready to print again.

Printing a Test Print -  Prusa Mendel commissioning Step 9 Printing a Test Print -  Prusa Mendel commissioning Step 10

Prusa Mendel Parts Help and Support


12.0 Maintenance of the Reprap Prusa Mendel 3D Printer – Prusa Mendel Build Manual

Some guidance and tips for looking after your 3d printer and helping to keep it working effectively and efficiently. The extent to which this guidance needs to be implemented will depend on how heavily you are using your 3D Printer. This guidance should be read in conjunction with the rest of this manual.

General

Visually check the printer before commencing a print to check everything is where it is supposed to be to prevent any unexpected problems, because the printer has many moving parts it is important to make sure nothing becomes disconnected or dislodged that goes un-noticed prior to commencing a print.

Endstops – Make sure they haven’t moved on their respective axis and that they are connected electrically
Axis – Make sure they are tightly gripped and don’t have any vertical or horizontal movement.

When sending manual commands to the printer from the Pronterface software, always pay attention to what the printer is actually doing and make sure you don’t issue any commands by accident. As a rule always move the axis in smaller steps ie 10mm at a time rather than 100mm at a time, this is because the printer is controlled serially and the commands will queue and execute sequently irrespective of what happens physically. Don’t ever over/aimlessly click on buttons in the software, as the commands will queue and keep sequentially operating.

For example, the z endstop becomes slightly loose and moves slightly, then when you home the z axis the endstop gets missed and the hot end crashes into your build bed, if you’re moving in smaller increments you are less likely to do any damage etc.

Because the printer communicates serially and commands are queued in batches, there can be a slight delay between pressing “pause” or “stop” and the printer actually stopping, so it’s handy to always have quick access to the power switch on the PSU, so in the event the printer behaves unexpectedly or you enter an inappropriate / erroneous command you can just cut the power before any damage is done ( this won’t damage the electronics).



12.1 Axis Lubrication

Regular lubrication of the X and Y Axis is important for the longevity and smooth running of your printer. These axis should always move without much resistance, if you were to lift one end of the printer the y carriage should move under it’s own weight by gravity. The rods can be lubricated with oil or grease. Ideally bearing grease should be used (from a local auto supplier) and apply generously to both the X Axis and Y Axis.

In terms of frequency, this will depend on how heavily you are using the printer, but as a general rule, the axis’s should never be “dry” to touch, they should be lightly lubricated.

When lubricating the axis it is also recommended to rotate the axis slightly to prevent bearing wear on the rod itself. Do this by loosening the bar clamps and rotating the rod slightly.



12.2 Hot End & Nozzle

Keep your Hot End Nozzle clean, don’t let molten plastic build up on it as this will cause issues when starting prints. Brillo/ Scotch Brite Pads or a scourer are a good way of keeping it clean. It’s easiest to keep it clean as you go, by using tweezers to remove excess plastic in between printing and not letting it stick to the nozzle.

Visually ensure wiring and connections haven’t moved and are still located in their correct positions, pay special attention to the hot end thermistor, if this moves away from the hot end heater block it will result in the electronics applying more power to the hot end to maintain it at a higher temperature as an offset to the thermistor being further away, this could result in the electronics cutting the power to the hot end as too much current is drawn. This would then result in the hot end cooling mid print, and then the filament will grind out in the extruder and you will need to reload the extruder and start the print again



12.3 Nuts & Bolts

Check the nuts and washers across the printer to ensure they are still tight and haven’t worked loose, as the printer move’s and vibrates a lot, it is prudent to check these regularly. It is important they don’t work loose as it can affect the geometry and stability of the 3D Printer



12.4 Extruder & Gears

The Extruder is one of the hardest working parts of the printer.

Every so often open the extruder Idler and clean out any loose plastic and plastic debris that may have built up on and around the hobbed bolt. Using a small tooth brush or hand held vacuum is very effective clear out any loose debris, obviously you should do this everytime you change filament anyway.

Visually check the drive and driven gears for wear and to ensure no teeth have broken or become damaged, this might not be obviously visible, make sure you look closely. This could result in uneven/consistent extrusion.

Check the drive and driven gears still consistently mate together tightly.

Check that the hot end is still tightly clamped into the extruder and is still located in it’s original position, in that it hasn’t moved or slipped at all.



12.5 Electronics

Always keep the electronics in an open, ventilated area, located in such away that you’re not going to drop any conductive debris on them ( such as nuts & washers etc).

Regularly check that the pc header connectors on the Ramps board haven’t worked loose or become disconnected, especially the Endstop and thermistor connections.

Every so often, check all of the slotted screw terminals on the the associated power connections on the RAMPS board and tighten them where necessary.

Make sure both the Bed Thermistor and Hot End Thermistors haven’t moved or dislodged from their positions on the printer.

Make sure the connectors on the endstops are still homed tight and in position.



12.6 Pulley Grub Screws & Belt Tensions

Make sure that the grub screws holding the X & Y Pulleys and the Extruder Drive Gear are tight and that the pulleys never/ can’t slip.

Over time and the more you use your 3d printer the X and Y timing belts will loosen slightly, so you need to check their tensions and tighten them if they have become loose or looser



12.7 Build Surface

Make sure you keep your build surface, clean, dry and free of oil/grease. In order for ABS Plastic to adhere to the build surface and to prevent warping, you will be using kapton tape on your build surface. The kapton tape will need to be replaced and re applied to the build plate when it gets damaged, scratched and scuffed. You can use your judgment as to when you need to, but to ensure a smooth base on the printed object, you’ll need to ensure the kapton tape is in good order.



12.8 Bed Leveling

When ever you move your printer or place it on a different surface, you should re level your bed as in section 11.0 Commissioning to ensure an even gap between the hot end nozzle and the build surface.

It is very important that your bed is correctly leveled, for example if the bed is too high in one corner of the build bed, when the hot end moves over that area of the bed it will drag and scrape on the bed, potentially damaging the hot end and the build bed surface.



12.9 Plastic Parts

Certain plastic parts on the printer are prone to wear more than other parts, so once you’re up and printing it would be prudent to print some spare parts for yourself.

Parts we recommend printing are the Extruder Drive Gear, The Extruder Driven Gear, The Extruder, X Carriage and Endstop Holders. The design files for these parts are included on the software CD that came with your Prusa Mendel 3D Printer kit or you can download them from our website http://www.nextdayreprap.co.uk/downloads . These parts are more prone to wear as they are either heavily used or regularly adjusted.



12.10 Bearings

You need to ensure all the LM8UU Bearings maintain their correctly seated placement within the plastic parts. This is especially important on the Y carriage, as these bearings can be knocked out of alignment with the bearing pillows, if the y carriage has been moved in an erroneous fashion. For example you move the y axis 100mm away from home by pressing the button in the pronterface software, but there is only 60mm left of free axis, so when the instruction is sent the printer keeps trying to move the Y Axis for another 40mm after it has hit the end, this could result in the bearings nudging within their mounting pillows. This would then cause the bed level to be changed without you realising, so when you went to print the hot end nozzle would either crash into part of the bed or be too far away from it.

Visually and physically check that all four of the LM88UU Bearings are mounted level and even within the printed plastic bearing pillows on the underside of the Y Carriage, if necessary re seat and align them ( as per section 5.0 Y Carriage Assembly).

For the X Carriage and Z Axis visually check the bearings are level and evenly located and that the cable ties are tight and tighten them as necessary.



Prusa Mendel Parts Help and Support