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Instructions: Fabrication Diagram

9. z Motors Mounting

6. Bed Metal Platform

Upper frame

7. Heated Bed Solder

8. Complete Bed Assembly

19.1-4

Assemble electronics

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Main Frame Assembly

10. Z

carriage Left

10. Z

carriage Right

10. 3D Printed Extruder Carriage

10. x Rod with Extruder

10. Extruder Carriage

Frame with Extruder Assembly

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Extruder

Belt

Chrome and Threaded Rods

12. Extruder Carriage with Extruder + Z Rods

3. Bottom frame

Y rails, rail mounts, linear bearings and carriage

Main Frame

13. front pulley assembly

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Build Details: Bed Idler

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  • Bed idler is built separately up to m4 t-nuts, then simply dropped in to frame.

1

2

Insert bolt through angle bracket hole

3

Add bearing sandwich with flanged bearings outside

4

Put on the second bracket, washer, locknut

5

Add m4x8 panhead bolt and t-nut (thread it on half way or 3 turns)

12 mm washer

QC: Stand up on allan wrench at 3, and don’t screw down nut all way at 4, and drop into rail + tighten, and then screw down nut all the way.

3:30

30 mm panhead bolt with 12 mm washer (12 mm washer not shown below)

Thread on t-nut half way

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Tools

  • M3 panhead uses 2 mm hex key
  • M4 panhead uses 2.5 mm hex key
  • M5 socket head uses 4 mm hex key
  • M4 socket head uses 3 mm hex key
  • 5/64 = 2 mm
  • 5/32= 4 mm

Sourcing;

  • 2 mm 10 piece insert - $10
  • 2.5 mm 10 piece inserts - $9

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Prusa i3 Build

Sat. Jan 30, 2016

See Prusa i3 Development

Steps: Documentation setup: 10 AM

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3D Printed:

Right Side

3D Printed:

Left Side

3D Printed:

Extruder Carriage

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Instructions: Alignment

  • Base frame: tighten securely on all 4 corners
    • Check perpendicularity with a precise square. +/- 1 mm over 40 cm
    • Once tightened loosely for fit and then retightened on a flat surface, precision is ok.
    • Precision comes from mount of print bed - bed bushings are mounted 90 mm off edge
    • Z precision comes from making the machine vertical - verticals are aligned 90 mm from the back of the frame

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Instructions: Configuration

  • Download Arduino and 3D printer code, upload to Arduino
  • Issue: x homing issue in 3D printer code
  • Download Repetier
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Workflow:

  • Download STL
  • Load into Repetier
  • Print!

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Assembly Guide Improvement Notes:

  • Alignment protocol and rationale is completely missing; this is the difference between fussing around for another day, vs following a protocol once
  • Full 3D CAD is missing
  • Instructions needed for starting the kapton tape roll unrolling;
  • Full Exploded Part Diagram should be up front
  • Label the printed parts
    • Use 3D printed labels
  • Do a Coffee Table Manual
    • Ex. Morgan (page 67) and Prusa (page 66) quality instructionals
  • Some pictures are missing (“Insert picture here”, page 3) and some pictures are inaccurate (“Ignore this and this in picture”, page 4)
  • Step 3.6 - don’t refer back to step 3, this step is actually different (no corner brackets) and it’s not clear whether it’s Step 3 or part 3 of that step
  • Step 3.8 - the picture looks different from what they tell you, there’s an extra L bracket
  • Step 3.9 - show orientation of corners - which goes inside the other? Show the motor mount in the photo to clarify orientation
  • Step 4.1 - use picture showing motor mount
  • Step 5.1 - show picture of measuring points
  • Step 5.2 - use picture that shows orientation of L bracket clearly
  • Step 6.4 - brackets should be put on bearings before they go on in Step 4.3
  • Step 7.5 - thermistor mounting is weak - should use some better way to secure thermistor.
  • Step 7.4 - Instructions do not say which side to solder on, nor L/R orientation of the wire - the loop orientation is shown only afterwards. Side does matter for performance - the heat elements should be facing up (next to glass).
  • Step 7.5 - Instructions do not say which side to solder thermistor - picture is shown only in next step. Overview of construction (exploded part diagrams) should cover the entire build, such as in FreeCAD. A FreeCAD script can be run to produce a video just by hiding/unhiding parts.
  • Step 9.2 - make the orientation of the plug on the motor clear in picture
  • Step 9.3 - 4.8 motor or 5.3 motor?
  • Step 10.1 - how far into the cylinder should the bearing go?
  • Step 10.3 - use a picture to show orientation of motor
  • Step 10.3 - this assembly ends up too loose, we added washers
  • Step 10.4 - align pulley teeth with hole in 3D Printed piece
  • Step 10.7 - this is difficult to get lined up, we need a trick
  • Step 10.7 - use picture that shows how far out nut should protrude after tightening
  • Step 10.9 - the casing for the bearing on the right of the photo was too tight, scraped as the bearing went in

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Assembly Guide Improvement Notes 2:

  • Extruder carriage is not moving smoothly on rods
  • Step 10.12 - it’s hard to push rods into holes, rotate don’t push.
  • Step 10.12 - when you put rods snug in holes, distance between is 295mm, should be 300mm. Show picture of measuring points.
  • Step 15.2 - picture shows different hardware from what’s in the box
  • Step 16 - Up-down orientation of motor L bracket is not mentioned, only in picture.
  • Step 13.1 - how tight? what should the vertical positioning be of the assembly in the holes?
  • Step 20 - state clearly orientation of connector
  • Step 21.4 - The wire ends attached in RAMPS connectors needs to be tinned, otherwise they’ll burn eventually.
  • Step 22.1 - Thermistor connector already mounted by Folgertech
  • Step 24 - All wire ends should be tinned. Bend PSU-ends of wires around screws (make “hook”) before tinning.

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Notes on Folgertech 2020 Prusa i3 design

Positive ones are black, negative ones are red

  • Licensing information not readily available
  • Hot end design is “as cheap as possible”. Will cause problems on high extrusion rates.
  • Extruder pinch (roller bearing) not readily visible. Complicates debugging if extrusion problems should occur
  • Power supply needs manual connecting. Dangerous and time consuming
  • Risk of shorting RAMPS by just plugging end stops backwards. Such small mistakes will definitely occur in workshops.
  • Risk of pushing out bearing balls when mounting x-carriage on rods. Rounding rod ends would mitigate this risk.
  • Two upgrades are planned from Folgertech:
    • Extended build plate 200 x 300 mm
    • Auto bed leveling with proximity sensor and aluminum plate
      • Access to this would give something to benchmark against
  • Motors look short -> won’t give much dynamic force -> limits max print speeds, less forgiving of small alignment mistakes
  • Glass print bed not included
  • RAMPS and power supply feed motor drivers 12V (RAMPS can’t feed much more). A higher voltage (>~ 17 V) would most probably give notably more force from motors due to voltage rise times in stepper driver.
  • RAMPS electronics need extension to support SD card. (Source for SD extension board €10, other source $2)
  • RAMPS sets microstepping manually (the kit supplier already did that)
  • RAMPS pins easily bent during transportation (requires some manual bending surgery)
  • Risk of mounting stepper driver chip backwards with RAMPS (Folgertech eliminated that risk by pre-assembling)
  • Large number of different screws and nuts is a problem during start of assembly
  • No specialized print surface tape (BuildTak or similar).
  • Heat bed needs to be soldered. The soldering needs to hold ~25 A
  • Rounded corners of 2020 extrusions makes calibration measuring harder
  • Wires are pre-cut and with connectors already
  • Motor wires identical length
  • Risk of easily over-tightening endstop holders. Not crucial but irritating.
  • Uses Kapton tape as heatshrink (page 37)

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Continued Notes on Folgertech 2020 Prusa i3 design

Positive ones are black, negative ones are red

  • Holes for M3 screws are too small for poking screws through. Very time consuming.
    • Examples: Step 6 for bearing mounts to the aluminum platform; extruder mounting to bearing carriage; Z Carriage left pulley; Z carriage right motor is ok - but need
  • Holes for linear bearings are also too small
  • Firmware not pre-configured
  • Four points to level print bed (instead of three)

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Folgertech 2020 Prusa i3 other builds

  • http://moosteria.blogspot.se/2015/05/3d-printer-project-part-2-unexpected.html
    • Took 10.3 hours for build, then to calibration...
  • Complete build described in 22 blog posts…

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Questions on Folgertech 2020 Prusai3 design

  • How large Y-rotation does X-carriage allow? (linear bearings sit close to each other)
  • Are zip ties around linear bearings rigid enough and simple enough to tighten?
  • What maximum feed rate does the spring-loaded direct extruder + hot end allow?
  • Is upper frame coupling to bottom frame rigid enough? (small metal L-mounts are used)

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Borosilicate sheet sources

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RAMPS Prices

  • Cheap clones: $5

http://www.ebay.com/itm/3D-Printer-Controller-Board-Module-For-Ramps-1-4-Reprap-Prusa-Mebdel-New-F5-/172015616360?hash=item280cee0168:g:ToIAAOSwAKxWXT4j

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  • Original: $80

https://ultimachine.com/content/ramps-pre-assembled-kit

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