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Initial work is beginning on plans inspired by McWire Cartesian Bot 1 2 plans, but we have switched to the WolfStrap concept to make our lives easier.

What we need to do yet

  1. Set up a microcontroller for driving motors from serial control
  2. Computer software to convert 3D model from Blender, etc. to something like G-Code
  3. Program the microcontroller to accept the above code

Since that wiki page is failing, here are some Flickr images: RepRap McWire Photos

Defining Metrics For Wood Part Size

Note: Overkill is allowed. For non-slab parts, an excess of size will not negatively impact performance. As we have an excess of wood, we can easily make this larger.

Wood sizes are:

  1. Type: Height Width
  2. Thick: 3/4" * 2.5"
  3. Thin: 3/4" * 1.5"


  1. Base & Y-Axis
    1. Base-X-axis = {Thick} (SliderX) + (Extruder Thick width)
    2. Base-Y-axis = {Thick} (SliderY) + (X-Vert-Support width) + (dist X-Vert-Support to edge of Base) + (dist extruder head to extruder mount) || {Thick} 4/3 * (SliderY)
      1. Only the Y axis has it's slider mounted; the X-axis is held above the working surface.


  1. X Axis & Support
    1. X-Axis = {Thin} (SliderX) + 2*(Support Height) + (Extruder Thick width)
    2. X-Vert Support = {Thick} (Z-Slider) + (Z-Extruder) + 2*(X-Axis Thick Width) + (X-Nut Thin Height) + (Base Thick Width)
      1. We have this awkward size because the extruder must be able to move through this whole volume; the extruder is long to allow it to print a height. Again, we can just overkill this part.


  1. Z-Axis
    1. Z-Axis = {Thin} (SliderX)


  1. Slabs
  2. Z-Extruder = {Thick} (Mounting Bracket) + (Clearance, 1")
  3. Z-Motor = {Thick} 2(Z-Slider Thin Width) + (Z Nut, Thin Height) || (Motor Width) + (Z-Slider Thin Width)
  4. Y-Nut = {Thin} 3/4*(Y-Axis) =< (Y-Axis)
  5. X-Nut = Z-Nut = {Thin} 2"


Therefore:

part class part thickness length # needed " needed total
Base Base-X-Axis Thick 20.5" 2x 41"
Base-Y-Axis Thick 24" 2x 48"
X Axis & Support X-Axis Thin 23.5" 2x 47"
X-Vert Support Thick 30" 2x 60"
Z-Axis Z-Axis Thin 18" 2x 36"
Slabs Z-Extruder Thick 5" 1x 5"
Z-Motor Thick 3.75" 1x 3.75"
Y-Nut Thin 13.5" 1x 13.5"
X-Nut & Z-Nut Thin 2" 2x 4"

For a total of 157.75" of thick and 105" of thin. As a reference, we have 16' = 192" of each.

Mechanical values

  • leadscrews X & Y 16 threads/in.
  • Z leadscrew 20 threads/inch
  • motor 1.8 deg./step

∴ X, Y quantum res. = 3200 and Z quantum res. 4000

  • for ease of computation, {X, Y, Z} virtual resolution will be 800