Heavy Mendel

Description

Heavy Mendel, a self replicating 3D printer/mill/PCB engraver

The design is inspired by the triangular frame of the reprap mendel, It will be heavier and more rigid to be able to mill plastic, engrave circuit board and print at high speed. Differences compared to the standard mendel :

• vertical X axis to quickly change the tool (extruder or spindle)
• M10 and M12 threaded rods instead of M8 for better frame stiffness
• 10mm smooth rods instead of 8mm for better axis stiffness
• Precision doubling belt configuration inspired by Madkite's design : http://www.thingiverse.com/thing:8852
• nema23 steppers for the X and Y axis instead of nema17
• Each axis will be equipped with 4 printed linear bearings : http://www.thingiverse.com/thing:16946

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Cable drive system

3D Files

stl files

• Frame stl files : http://reprap.org/wiki/File:Heavy_Mendel_frame_stls.zip
• X axis stl files : http://reprap.org/wiki/File:Heavy_Mendel_X_axis_stls.zip
• Y axis stl files : http://reprap.org/wiki/File:Heavy_Mendel_Y_axis_stls.zip
• Z axis stl files : http://reprap.org/wiki/File:Heavy_Mendel_Z_axis_stls.zip

sketchup files

• Frame : http://reprap.org/wiki/File:Heavy_Mendel_frame_sketchup.zip
• X axis : http://reprap.org/wiki/File:Heavy_Mendel_x_axis_sketchup.zip
• Y axis : http://reprap.org/wiki/File:Heavy_Mendel_y_axis_sketchup.zip
• Z axis : http://reprap.org/wiki/File:Heavy_Mendel_z_axis_sketchup.zip
• Complete printer : http://reprap.org/wiki/File:Heavy_Mendel_complete_sketchup.zip

Electronics

Stepper driver

• Schematic : http://reprap.org/wiki/File:Heavy_Mendel_stepper_driver_schematic.pdf
• Board : http://reprap.org/wiki/File:Heavy_mendel_stepper_driver_board.pdf
• PCB : http://reprap.org/wiki/File:Heavy_mendel_stepper_driver_PCB.pdf
• Kicad project files : http://reprap.org/wiki/File:Heavy_mendel_stepper_driver.zip

soft start

• Schematic : http://reprap.org/wiki/File:Heavy_mendel_Soft_start_schematic.pdf
• Board : http://reprap.org/wiki/File:Heavy_mendel_soft_start_board.pdf
• PCB : http://reprap.org/wiki/File:Heavy_mendel_soft_start_pcb.pdf
• Kicad project files : http://reprap.org/wiki/File:Heavy_mendel_soft_start.zip

axis panel

• Schematic : http://reprap.org/wiki/File:Panel_axis_schematic.pdf
• Board : http://reprap.org/wiki/File:Panel_axis_board.pdf
• PCB : http://reprap.org/wiki/File:Panel_axis_pcb.pdf
• Kicad project files : http://reprap.org/wiki/File:Panel_axis.zip

extruder panel

• Schematic : http://reprap.org/wiki/File:Panel_extruder_schematic.pdf
• Board : http://reprap.org/wiki/File:Panel_extruder_board.pdf
• PCB : http://reprap.org/wiki/File:Panel_extruder_pcb.pdf
• Kicad project files : http://reprap.org/wiki/File:Panel_extruder.zip

probe

• Schematic : http://reprap.org/wiki/File:Probe_schematic.pdf
• Board : http://reprap.org/wiki/File:Probe_board.pdf
• PCB : http://reprap.org/wiki/File:Probe_pcb.pdf
• Kicad project files : http://reprap.org/wiki/File:Probe.zip

extruder switch

• Schematic : http://reprap.org/wiki/File:Heavy_mendel_Extruder_switch_schematic.pdf
• Board : http://reprap.org/wiki/File:Heavy_mendel_Extruder_switch_board.pdf
• PCB : http://reprap.org/wiki/File:Heavy_mendel_Extruder_switch_pcb.pdf
• Kicad project files : http://reprap.org/wiki/File:Heavy_mendel_Ext_switch.zip

Extruder switching motor driver

• Schematic : http://reprap.org/wiki/File:Heavy_mendel_Servo_driver_schematic.pdf
• Board : http://reprap.org/wiki/File:Heavy_mendel_Servo_driver_board.pdf
• PCB : http://reprap.org/wiki/File:Heavy_mendel_Servo_driver_pcb.pdf
• Kicad project files : http://reprap.org/wiki/File:Heavy_mendel_Servo_driver.zip

temperature controller

• Schematic : http://reprap.org/wiki/File:Heavy_Mendel_Temp_controller_schematic.pdf
• Board : http://reprap.org/wiki/File:Heavy_Mendel_Temp_controller_board.pdf
• PCB : http://reprap.org/wiki/File:Heavy_Mendel_Temp_controller_PCB.pdf
• Kicad project files : http://reprap.org/wiki/File:Heavy_Mendel_Temp_controller.zip

extruders and fans power stage

• Schematic : http://reprap.org/wiki/File:Heavy_Mendel_Out_ext-fan_schematic.pdf
• Board : http://reprap.org/wiki/File:Heavy_Mendel_Out_ext-fan_board.pdf
• PCB : http://reprap.org/wiki/File:Heavy_Mendel_Out_ext-fan_PCB.pdf
• Kicad project files : http://reprap.org/wiki/File:Heavy_Mendel_out_ext-fan.zip

Bed and aux power stage

• Schematic : http://reprap.org/wiki/File:Heavy_Mendel_Power_out_schematic.pdf
• Board : http://reprap.org/wiki/File:Heavy_Mendel_Power_out_board.pdf
• PCB : http://reprap.org/wiki/File:Heavy_Mendel_Power_out_PCB.pdf
• Kicad project files : http://reprap.org/wiki/File:Heavy_Mendel_Pwr_outputs.zip

Extruder

The heater is made from an M6 insert with the external thread removed :

The tip is an acorn nut drilled with a 0,5mm drill-bit and hammered to reduce the hole size :

To keep the entrance of the hot-end cold, an assembly of aluminum plates and brass nuts forms a heat sink :

• Stl files : http://reprap.org/wiki/File:Heavy_Mendel_extruder_stls.zip
• Sketchup assembly : http://reprap.org/wiki/File:Heavy_Mendel_extruder_assembly.skp

Dual extruder

The unused tip is lifted by a few millimeters and closed by a rocking mechanism activated by a cheap RC servo (T2M D190)

• Stl files : http://reprap.org/wiki/File:Heavy_Mendel_dual_extruder_stls.zip
• Sketchup assembly : http://reprap.org/wiki/File:Heavy_Mendel_dual_extruder_assembly.zip

Heated Bed

It is built from 3mm glass, 10mm thick cork, small nails and for heating element, copper wire from a stepper motor found in an old printer.

Details :

The bed didn't heat-up enough on 12V if I connect it on the two sides, so I made the connexion between the center an the sides. It heats-up to 120°C on 12V, maybe higher if I didn't set the safety cutoff temperature at 120°C.

Small PCB 10x10cm heated bed :

• PDF : http://reprap.org/wiki/File:Heavy_Mendel_heat_bed_100x100.pdf
• SVG : http://reprap.org/wiki/File:Heavy_Mendel_heat_bed_100x100.svg

Accessories

chuck

• 4-jaws chuck : http://reprap.org/wiki/File:Heavy_mendel_Chuck.zip

hobbing tool

• Schematic : http://reprap.org/wiki/File:Heavy_Mendel_Hobbing_Tool_Schematic.pdf
• Board : http://reprap.org/wiki/File:Heavy_Mendel_Hobbing_Tool_Board.pdf
• stl files : http://reprap.org/wiki/File:Heavy_Mendel_Hobbing_tool_stls.zip

Heavy Mendel RepRap discussion forum