OSE Prusa

From Open Source Ecology
Jump to: navigation, search

OSE Prusa

Based on a Chinese version of the Prusa i3 printer, this represents a simple and low-part-count option for the Open Source Ecology product system. (Nov. 22, 2019 We are in the process of replicating this printer and will assemble it in Guyana in late November, 2019.) OSE Prusa Slideshow

Bill of Materials

OSE Prusa Bill of Materials

Build Instructions

  1. Purchase and organize all parts from the Bill of Materials.
  2. Follow the suggested directions in the following sections:

Frame

  1. Make cuts in the 20mmx20mm aluminum extrusions: 400mmx3; 250mm*2; 320mm*2
  2. Slide T-Nuts for the Y Axis Idler, Motor Mount and Mounting Brackets onto the 250mm aluminum extrusions
  3. Slide T-Nuts for the Z-Axis Motor Mounts and Vertical Frame Mounts on two 400mm aluminum extrusions
  4. Complete the 290mmx400mm horizontal frame by assembling a rectangle using the 290mm and 400mm extrusions and four corner brackets.
  5. Place three corner brackets and one printer foot / printer foot bracket as feet for the horizontal frame.

X-Axis

  1. Attach the X-Axis Motor to the X-Axis Motor Mount.
  2. Place three LM8UU Linear Bearings in the X-Axis Carriage Bracket and fasten them in place with small zip ties.
  3. Attach the X-Axis Motor Mount and X-Axis Carriage Bracket to the X-Axis Motor with two 8mm smooth rods (300mm).

Y-Axis

  1. Attach the Y-Axis Motor to the Y Axis Motor Mount and both onto the Horizontal Frame.
  2. Attach the Y-Axis Pulley to the Y Axis Idler Using an M5 bolt and nut.
  3. Attach the Y-Axis Idler to the Horizontal Frame.
  4. Assemble two 320mm extrusions with one 400mm extrusion to form the vertical frame.
  5. Attach the Vertical Frame to the Horizontal Frame using two corner brackets and T-Nuts.
  6. Attach LM8UU bearings to each of the Bed Mounting Brackets using Zip Ties.
  7. Attach the Bed Mounting Brackets and Y-Axis Belt Holder to the aluminum bed plate.
  8. Slide two 8mm rods through the LM8UU bearings.
  9. Attach the Aluminum Bed Plate to the Horizontal Frame using the Y Axis Mounting Brackets. Make sure they are parallel and that the bed slides easily before tightening the screws.
  10. Attach the Y Axis Belt around the Y-Axis Motor, Idler and Belt Holder.
  11. Use small Zip Ties to hold the Y-Axis Belt in place with reasonable tension.
  12. Further tension the Y-Axis Belt with a Clothes Pin Spring.

Z-Axis

  1. Attach the Z-Axis Top Left and Right Brackets to the front of the Vertical Frame Crossbar using T-Nuts.
  2. Attach the Z-Axis Motors to the Z-Axis Motor Mounts using M3 bolts.
  3. Attach the Z-Axis Couplers to the Z-Axis Acme Rods using the associated set-screws.
  4. Place the Z-Axis Couplers on the Z-Axis Motor Axles.
  5. Place the 8mm Smooth Rods in the related holes on the Z-Axis Motor Mounts.
  6. Place the Brass Nuts of X-Axis on the Z-Axis by turning the Z-Axis Acme Rods.
  7. Place the Z-Axis Smooth Rods in the related holes on the Top Left and Right Brackets.
  8. Tighten the Top Left and Right Brackets when you have made the Z-Axis Vertical and ensured that the X-Axis may move smoothly up and down.

Extruder

  1. Attach the Aluminum Extruder Block to the lower two holes of the Extruder Motor and Extruder Mounting Bracket using M3 screws.
  2. Attach the Extruder Tube through the 6mm threaded hole of the Aluminum Extruder Block.
  3. Wind two 6mm nuts up the Extruder Tube to make sure that it stays in place. The top of the Extruder Tube should be even with the top of the Aluminum Extruder Block.
  4. Attach the Extruder Heater Block and Brass Nozzle to the Extruder Tube.
  5. Attach the Extruder Idler to the Extruder Idler Bracket using an M4 screw and Nut
  6. Attach the Extruder Bracket and Idler Bracket to the two top holes of the Extruder Motor using M3 screws.
  7. Place the Extruder Tensioner Spring in the Extruder between the Idler Bracket and the Extruder Bracket.

Electronics

  1. Solder wires on the Heated Bed.
  2. Attach the Bed Thermistor to the Heated Bed
  3. Place the Heating Resistor in the Extruder Heater Block.
  4. Place the Extruder Thermistor in the Extruder Heater Block.
  5. Place the X, Y and Z End-Stops in their Respective Positions on the Printer.
  6. Prepare a Power Cable for the Power Supply.
  7. Prepare Wires to run from the Power Supply to the RAMPS Board.
  8. Prepare the Pololu Heat Sinks for the Pololu Drivers
  9. Carefully Insert the Pololus in Position on the RAMPS Board.
  10. Place the RAMPS Board on the Arduino.
  11. Place the RAMPS and Arduino on the Back of the Vertical Frame Using the T-Nuts (already on the vertical frame) and M4 screws.
  12. Run the wires of each electronics device along the frame to the RAMPS Board. Wrap the Extruder Wires and Y-Axis Wires in a Spiral Cable Carrier. Attach the wires neatly and securely to the framw using zip ties.
  13. Attach all wires to the RAMPS Board.

Part Library

Here are the parts for the printer: (Nov. 23, 2019 - Note that the Y Belt Holder still needs to be drawn up in FreeCAD; we are still working on some minor edits to some of the parts - for the moment, we are drilling some holes in them for example)

Extruder

This printer makes use of the OSE D3D Simple Extruder

Build Notes - December 1, 2019

  • The build was completed relatively quickly despite the fact that the printed parts were all first prototype copies. Most of the bolt holes had to be drilled slightly. There were several other parts that needed additional holes drilled:

3D Printing Issues

  1. X-Axis Motor Mount - Additional hole to allow for the smooth rod to pass through. Enlarge motor mount holes. Increase diameter of brass nut holes (4 for 3m bolts and one for the brass nut itself)
  2. X-Axis Idler - Additional hole to allow for the smooth rod to pass through. Enlarge holes for bearing bolt. Increase diameter of brass nut holes (4 for 3m bolts and one for the brass nut itself)
  3. Extruder Mount Bracket - increase the width of the GT2 belt slightly
  4. Y-Axis Motor Mount - Increase hole diameter of motor mount holes.
  5. Y-Axis Idler - increase diameter of holes for the bearing bolt
  6. Z-Axis Top Brackets - 4mm holes for attachment to frame
  7. Z-Axis Motor Mounts - 3mm holes need to enlarge.
  8. Bed Brackets - Small notches for zip ties.

Other Issues

  1. Extruder Aluminum Block - Holes were not quite the right separation - had to be drilled slightly

Notes for Tiffany and Ganesh

  • to prepare the OSE Prusa for its first print test.
  • Here is a checklist of items to prepare:
  1. Install the spring on the extruder.
    1. The idler bracket may need to be removed to do so.
    2. If the spring is too tight, the extruder motor may not be able to turn.
      1. Try increasing the extruder Pololu voltage to some value between 0.5V and 1.0V if this is the case (keep the voltage as low as possible)
    3. If the spring is too loose, the gear will slip on the filament. Try putting a small object under the spring to slightly increase its tension.
  2. Slightly shorten a few of the screws on the Extruder.
  3. Solder the two fans with longer wires. Cut the fan wire and solder the longer piece in between so that you may plug the Extruder fan to the board at the D9 terminals.
  4. Position the large fan on the top frame crossbar at a 45 degree angle from vertical, directed towards the RAMPS and Arduino. Plug the large fan directly into the 12V power supply.
  5. Tighten the springs on the printer bed so that it stays in place as the Y-Axis moves
  6. Fasten the power supply to the side of the printer.
  7. Run the Z-Axis motor wires and Endstop Wires along the frame and secure them with Zip Ties
  8. Create a roller for the filament. A metre stick suspended by two boxes may act as a quick start in this regard.
  9. Realign and reposition the Z-Axis Endstop so that the extruder tip stops just above the printer bed.
  10. Cover the bed with masking tape.
Retrieved from "https://wiki.opensourceecology.org/index.php?title=OSE_Prusa&oldid=204716"