My attempt to build an improved Prusa i3 MK3 3D printer clone with Full Bear frame from scratch
- Purchase the parts and the materials according to the Bill of Materials section below
- Print required 3D printed tools and parts as listed below
- Note the print priority:
- Priority 1 parts are required for assembling the printer
- Priority 2 parts are useful for continious printer operation
- Priority 3 parts are not essential, mostly decorative parts
- It is possible to print priority 2 and priority 3 parts once the printer is assembled, using the printer itself
- Note the print priority:
- Follow the Prusa i3 Bear Full Upgrade MK3 Assembly Instruction steps 1 - 9 to assemble the v-slot frame, mount Y rods and Y motor
- Note: The feet and the power supply lower mount can be installed later
- Note: Use thread locker for metal thread to metal thread (not metal thread to plastic)
- Follow the Original Prusa i3 MK3S kit assembly guide - Y-axis assembly steps 24 - 27 to assemble the Y carriage
- Note: Lubricate linear bearings before installation
- Follow the Prusa i3 Bear Full Upgrade MK3 Assembly Instruction step 10, bullets 1 - 5 to mount the Y carriage on the Y rods (330 mm)
- Note: Do not follow the Y belt installation instructions - bullets 6 - 9
- Follow the Original Prusa i3 MK3S kit assembly guide - Y-axis assembly steps 33 - 42 to assemble and tension the Y belt, and consume 15% of gummy bears
- Note: All3D Makers MK3 Y carriage does not have threaded M3 holes for Y belt holder and tensioner. I had to use longer M3x14 mm screws and nylock nuts to secure these parts. Prusa MK3 uses M3x10mm screws instead.
- Follow the Bear Extruder And X Axis Assembly - X axis to build the X axis.
- Note: Lubricate linear bearings before installation
- Follow the Prusa i3 Bear Full Upgrade MK3 Assembly Instruction steps 11 - 13 to install Z motors and Z rods (320 mm), mount the X axis, and Z tops
- Follow the Bondtech for Prusa i3 - Assembly and Installation Manual to build the extruder and mount it on the X axis. Refer to Bear X axis and Extruder - Bondtech Prusa Upgrade Extruder Assembly Guide for X carriage mounting instructions and drawings. Install the X belt, and tighen it using two M3x18mm screws on X idler
- Follow the Original Prusa i3 MK3S kit assembly guide - Heatbed and PSU assembly steps 1 - 17 to assemble the heatbed
- (If priority 2 parts are available) Follow the Prusa i3 Bear Full Upgrade MK3 Assembly Instruction steps 14 and 15 to mount the LCD and the power supply unit.
- Note: The LCD module I've got has a slightly bigger than standard PCB, and I had to file it to make it fit.
- (If priority 2 parts are available) Follow the Universal Zaribo Einsy Box instructions to install the Einsy Enclosure
- Note: The Bear Einsy enclosure is slightly wider than it should be to fit properly. I had to file a corner to make it fit.
- (If priority 3 parts are available) install end caps according to the Prusa i3 Bear Full Upgrade MK3 Assembly Instruction steps 14 and 19
- Follow the Original Prusa i3 MK3S kit assembly guide - Electronics assembly to wire the motors, the headbed, and the extruder to Einsy Rambo module.
- (If priority 3 parts are available) route and secure the cables according to the Prusa i3 Bear Full Upgrade MK3 Assembly Instruction step 18
- Perform the pre-flight check according to the Original Prusa i3 MK3S kit assembly guide - Preflight check
- Calibrate the printer according to the Prusa i3 Bear Full Upgrade MK3 Assembly Instruction steps 20 and 21.
- (If priority 2 parts were not initially printed) Print priority 2 parts, and follow the steps 8 and 9 above to mount the LCD module, the power supply unit, and the Einsy enclosure.
- (If priority 3 parts were not initially printed) Print priority 3 parts, and follow the steps 10 and 12 above to install end caps and route the wires
- Download Bondtech Firmware Variation Updates For Prusa 3D Printers - For MK3S Using AllMetal V6
- Flash the firmware using PrusaSlicer Configuration -> Flash printer firmware menu
To be completed
To be completed
| Assembly/Component Type | Description | Quantity | Price | Possible sources and notes |
|---|---|---|---|---|
| Aluminum Frame and Hardware | Full Bear MK3 Upgrade Kit - Detailed BOM | 1 | $124.99 | ALL3D Makers MK3 Bear Upgrade |
| 3D Printed Tool | Full Bear MK3 - build_helper_106mm | 1 | Filament | Print (priority 1) |
| 3D Printed Tool | Linear Bearing Greasing cap - Linear_Bearing_Greaser_-_LM8UU | 1 | Filament | Print (priority 1) |
| 3D Printed Tool | Bondtech Extruder PTFE Cutter 6.3 mm | 1 | Filament | Print (priority 1) |
| 3D Printed Part | Full Bear MK3 - rod_holder | 4 | Filament | Print (priority 1) |
| 3D Printed Part | Full Bear MK3 - y_idler_23 | 1 | Filament | Print (priority 1). Note: 5 mm bore version for E3D 2GT 20T idler |
| 3D Printed Part | Full Bear MK3 - y_motor_mount | 1 | Filament | Print (priority 1) |
| 3D Printed Part | Full Bear MK3 - z_motor_mounts | 1 (total of 2 parts) | Filament | Print (priority 1) |
| 3D Printed Part | Full Bear MK3 - z_motor_mount_front | 2 | Filament | Print (priority 1) |
| 3D Printed Part | Full Bear MK3 - z_tops | 1 (total of 2 parts) | Filament | Print (priority 1) |
| 3D Printed Part | Full Bear MK3 - foot | 4 | Filament | Print (priority 2) |
| 3D Printed Part | Full Bear MK3 - psu_lower_mount | 1 | Filament | Print (priority 2) |
| 3D Printed Part | Full Bear MK3 - psu_upper_mount | 2 | Filament | Print (priority 2) |
| 3D Printed Part | Full Bear MK3 - lcd_support_a | 1 | Filament | Print (priority 2) |
| 3D Printed Part | Full Bear MK3 - lcd_support_b | 1 | Filament | Print (priority 2) |
| 3D Printed Part | Full Bear MK3 - cable_clip_lcd | 6 | Filament | Print (priority 3) |
| 3D Printed Part | Full Bear MK3 - cable_clip_round | 5 | Filament | Print (priority 3) |
| 3D Printed Part | Full Bear MK3 - cable_clip_ziptie | 3 | Filament | Print (priority 3) |
| 3D Printed Part | Full Bear MK3 - end_caps | 2 (total of 4 parts) | Filament | Print (priority 3) |
| 3D Printed Part | Full Bear MK3 - end_cap_z_axis | 2 | Filament | Print (priority 3) |
| 3D Printed Part | Bear Extruder and X Axis MK3 - x_carriage | 1 | Filament | Print (priority 1) |
| 3D Printed Part | Bear Extruder and X Axis MK3 - x_end_motor | 1 | Filament | Print (priority 1) |
| 3D Printed Part | Bear Extruder and X Axis MK3 - x_end_idler | 1 | Filament | Print (priority 1) |
| 3D Printed Part | Bear Extruder and X Axis MK3 - x_end_idler_idler_mount | 1 | Filament | Print (priority 1). Note: 5 mm bore version for E3D 2GT 20T idler |
| 3D Printed Part | Bear Extruder and X Axis MK3 - cable_guide_back_a | 1 | Filament | Print (Priority 1). |
| 3D Printed Part | Bear Extruder and X Axis MK3 - cable_guide_back_b | 1 | Filament | Print (Priority 1). |
| 3D Printed Part | Bear Extruder and X Axis MK3 - bondtech_x_carriage_mk3 | 1 | Filament | Print (priority 1) |
| 3D Printed Part | Bear Extruder and X Axis MK3 - x_carriage_back | 1 | Filament | Print (priority 1) |
| 3D Printed Part | Bondtech Extruder MK3S Sensor Add-on | 1 | Filament | Print (priority 3) |
| 3D Printed Part | Original Prusa i3 MK3S - y-belt-holder | 1 | Filament | Print (priority 1) |
| 3D Printed Part | Original Prusa i3 MK3S - y-belt-tensioner | 1 | Filament | Print (priority 1) |
| 3D Printed Part | Original Prusa i3 MK3S - z-screw-cover | 2 | Filament | Print (priority 1) |
| 3D Printed Part | Original Prusa i3 MK3S - plug-aligner | 1 | Filament | Print (priority 3) |
| 3D Printed Part | Universal Zaribo Einsy Box - 021._MK3_Bear_Einsy_Body_NO_RASP_v5.stl | 1 | Filament | Print (priority 2) |
| 3D Printed Part | Universal Zaribo Einsy Box - 020._MK3_Bear_Einsy_Cover_NO_RASP_v5.stl | 1 | Filament | Print (priority 2) |
| 3D Printed Part | Universal Zaribo Einsy Box - EinsyBox-CableCover1-2x.stl | 2 | Filament | Print (priority 2) |
| 3D Printed Part | Universal Zaribo Einsy Box - EinsyBox-CableCover2-1x.stl | 1 | Filament | Print (priority 2) |
| 3D Printed Part | LCD Cover for Prusa Bear Upgrade | 1 | Filament | Print (priority 2). Alternatives: Original Prusa i3 MK3S - LCD cover; LCD knob, or Prusa Bear LCD cover |
| 3D Printed Part | Original Prusa i3 MK3S - Heatbed cable cover | 1 | Filament | Print (priority 1) |
| Bearing | LMU8 Linear Bearing | 10 | $55.50 | Misumi LMU8 |
| Metal Rod | Z-Axis Rod - 8 mm diameter, 320 mm length | 2 | $24 | Misumi PSFJ8-320 |
| Metal Rod | Y-Axis Rod - 8 mm diameter, 330 mm length | 2 | $24 | Misumi PSFJ8-330 |
| Metal Rod | Z-Axis Rod - 8 mm diameter, 370 mm length | 2 | $24 | Misumi PSFJ8-370 |
| Belt | 2GT Belt | 2 | $14.54 | Misumi GBN8522GT-60 |
| Idler | 2GT 20 Tooth Idler, 6 mm width, 5 mm bore | 2 | £10.40 | E3D M-IDLER-T-GT2-P20-6-A-P5-H100 |
| Pulley | 2GT 16 Tooth Pulley, 6 mm width, 5 mm bore | 2 | £7.00 | E3D M-PULLEY-GT2-16T-6-P5-C-H155 |
| Dowel Pin | Dowel Pin 15.8 mm length, 5mm diameter | 2 | $1.69 | All3D Makers Bear X Axis Dowel Pin for E3D Gates 5mm bore idler |
| Electronics Assembly | Einsy Rambo 1.1 | 1 | $120.00 | UltiMachine EINSY RAMBo 1.1, All3D Makers MK3 EINSY RAMBo |
| Electronics Assembly | 2004 LCD Display - RepRapDiscount Smart Controller | 1 | $18.49 | All3D Makers MK3/MK2.5/MK2 LCD Display |
| Fan | Print cooling fan | 1 | $8.69 | All3D Makers MK3 Part Cooling Fan |
| Fan | Hotend fan | 1 | $13.69 | All3D Makers Sunon MF40100V1-1000U-G99 Hotend Cooling Fan |
| Electronics Assembly | PINDA 2 sensor | 1 | $15.99 | All3D Makers P.I.N.D.A 2 Inductive Sensor |
| Electronics Assembly | Filament sensor | 1 | $11.69 | All3D Makers MK3S IR Sensor Kit for New Bear Extruder |
| Heatbed | MK52 headbed | 1 | $68 | 3DPrintronics MK52 Heat bed for Prusa MK3. Note: Order 24V version with mounting hardware and thermistor. Optionally order MK3 Y carriage ($24), PINDA 2 sensor ($11), and Spring Steel Sheet ($45). |
| Electronics Assembly | MK3 24V Power Supply | 1 | $69.99 | All3D Makers 24V MK3 Power Supply Assembly with Power Panic |
| Motors kit | Stepper motors kit | 1 | $124.99 | All3D Makers Motor Kit for Bear Upgrade, MK2/3, Haribo and Zaribo Mod |
| Aluminum Y carriage | Prusa i3 MK3 Aluminum Y carriage | 1 | $38.99 | All3D Makers Prusa i3 MK3 Aluminum Y carriage |
| Spring Steel Sheet | MK3 Spring Steel Sheet | 1 | $25.75 | BuildTak FlexPlate MK3 - 9.5"x10" |
| Print Surface | Print Surface | 1 | $14.25 | BuiltTak Original 3D Printing Surface - 9"X10" |
| Miscellanous Hardware | U-Bolts for LMU8U Bearings and nyloc nuts | 1 set | $7.69 | All3D Makers U-Bolts for LMU8U Bearings |
| Miscellanous Hardware | Textile sleeves for headbed and extruder cables | 1 set | $5.69 | All3D Makers MK3/MK2.5 Heatbed and Extruder Textile Sleeve |
| Miscellanous Hardware | 3 mm x 50 cm Nylon Filament | 1 | $0.69 | All3D Makers MK3/MK2.5/MK2S Extruder Nylon Guide |
| Extruder | Bondtech MK2/MK2S/MK3 upgrade kit with Bondtech gears | 1 | $115 | All3D makers Prusa i3 MK2/MK2S Extruder Upgrade |
| Hotend | E3D V6, 1.75 mm nozzle, 24V | 1 | £43.00, $79.99 | E3D V6-175-24V, All3D Makers MK3 E3DV6 Assembled Hotend |
| Screw | M4 x 10mm button socket screw | 2 | $0.42 | Fastenal MB2530010A20000 2 - power supply upper mount |
| Screw | M3 x 8mm socket cap screw | 6 | $1.06 | Fastenal MS2510008A20000 6 - Einsy enclosure |
| Screw | M3 x 10mm socket cap screw | 32 | $5.91 | Fastenal MS2510010A20000 3 - Y motor mount 2 - Y belt holder and tensioner 2 - headbed cable assembly 3 - headbed cable cover 6 - X end motor and idler 6 - X carriage 8 - Einsy enclosure 2 - LCD enclosure |
| Screw | M3 x 12mm socket cap screw | 8 | $1.67 | Fastenal MS2510012A20000 8 - Z motor mounts |
| Screw | M3 x 14mm socket cap screw | 2 | $0.18 | Fastenal MS2510014A20000 2 - Y belt holder and tensioner |
| Screw | M3 x 18mm socket cap screw | 13 | $5.89 | Fastenal MS2510018A20000 9 - X end motor and idler 3 - X carriage 1 - power supply lower mount |
| Screw | M3 x 30mm socket cap screw | 1 | $0.32 | Fastenal MS2510030A20000 1 - Y belt holder and tensioner |
| Screw | M3 x 40mm socket cap screw | 4 | $1.45 | Fastenal MS2510040A20000 4 - X carriage |
| Nut | M3 hex nut | 27 | $1.98 | Fastenal MN2510000A20000 2 - Y belt holder and tensioner 3 - headbed cable cover 3 - X carriage 8 - X end motor and idler 10 - Einsy enclosure 1 - power supply lower mount |
| Nut | M3 nyloc nut | 7 | $1.12 | Fastenal 1L2510000A20000 3 - Y belt holder and tensioner 2 - headbed cable assembly 2 - X end idler mount |
| Nut | M3 square nut | 8 | $1.60 | Fastenal 0161907 4 - X carriage 4 - Einsy Enclosure |
| Washer | M3 x 7 mm washer | 10 | $0.32 | Fastenal MW6330000A20000 8 - Z motor mounts 2 - headbed cable assembly |
| Filament | 1 kg PETG | 1 | $24.99 | Amazon eSUN 3D 1.75mm PETG Orange Filament 1kg |
| Lubricant | Super Lube 21030 Synthetic Grease | 1 | $4.69 | Amazon Super Lube 21030 Synthetic Grease (NLGI 2), 3 oz Tube |
| Thread Locker | Medium Strength (Blue) Thread Locker | 1 | $5.57 | Amazon Vibra-TITE 121 Medium Strength Removable Anaerobic Threadlocker, 10ml Bottle, Blue |
| Assembly/Component Type | Description | Quantity | Price | Possible sources and notes |
|---|---|---|---|---|
| 3D Printed Part | Bondtech extruder add-on - Sensor_Body_Bowden.stl | 1 | Filament | |
| 3D Printed Part | Bondtech-Prusa_i3_MK3S-Reverse_Bowden-Sensor_Cover.stl | 1 | Filament | |
| 3D Printed Part | Lever.STL | 1 | Filament | |
| 3D Printed Part | Bear Extruder and X Axis MK3 vslot_mount_pc4-m10 | 1 | Filament | |
| 3D Printed Part | Spool Holder for 20mm V-Slot | 1 | Filament | |
| Hardware | PTFE Tubing - 1.75 mm x 1 meter PC4-M10*0.9 Straight-Thru Fittings x2 |
1 set | $15.99 | Capricorn Premium Bowden Tubing SKU 2001 Note: When at tubing page, add fittings from the drop down list on the right. |
| Screw | M3 x 16mm socket cap screw | 1 | $0.11 | Fastenal MS2510016A20000 |
| Assembly/Component Type | Description | Quantity | Price | Possible sources and notes |
|---|---|---|---|---|
| 3D Printed Part | Full Bear MK3 - rambo_base_lower_mount | 1 | Filament | Print (priority 3) |
| 3D Printed Part | Full Bear MK3 - rambo_base_upper_mount | 1 | Filament | Print (priority 3) |
| 3D Printed Part | Full Bear MK3 - rambo_lid_lower_hinge | 1 | Filament | Print (priority 3) |
| 3D Printed Part | Full Bear MK3 - rambo_lid_upper_hinge | 1 | Filament | Print (priority 3) |
| 3D Printed Part | Original Prusa i3 MK3S - Einsy-base | 1 | Filament | Print (priority 3) |
| 3D Printed Part | Original Prusa i3 MK3S - Einsy-doors | 1 | Filament | Print (priority 3) |
| 3D Printed Part | Original Prusa i3 MK3S - Extruder-cable-clip | 1 | Filament | Print (priority 3) |
| 3D Printed Part | Original Prusa i3 MK3S - Heatbed-cable-clip | 1 | Filament | Print (priority 3) |