doc/how-to-build.txt

   1 --------------------------------------------
   2 How to Assemble the Reprap Wilson 3D printer
   3 Written by Martin Rice <mrice411@gmail.com>
   4 --------------------------------------------
   5
   6 1. Introduction / Overview of components
   7
   8         A detailed bill of materials with measurements can be found / generated from
   9         the wilson-bom.ods spreedsheet in /docs/.  Below is a concise overview of
  10         the purpose of the mechanical components you will need:
  11
  12         1.1 Frame Components
  13                 The frame is built from four pieces of 2020 Aluminum extrusion, two
  14                 threaded rods (M10 is the default), and plastic (RP) parts which
  15                 are used for joinery (and in some cases also for holding rods described
  16                 in section 1.2 below).  The plastic parts consist of 10 separate parts:
  17                 6 of which hold the extrusions, two of which hold the threaded rods
  18                 (the Y ends), and the final two which join the horizontal (threaded rod)
  19                 section to the upright frame.
  20
  21         1.2 Motion Control
  22                 The design uses three sets of linear rods (6 total) and four stepper
  23                 motors for motion control.
  24
  25                 Similarly to earlier reprap designs in the Mendel heritage, the Wilson
  26                 design has a horizontally mounted print bed which is restricted to
  27                 motion only in the Y-axis (front to back), and a carriage which moves
  28                 the     extruder along the X-axis (left to right).  The X and Y axis are
  29                 belt driven, by one stepper motor each that is mounted at one end of
  30                 the respective axis (these are called the "motor ends").  At the
  31                 opposite end of each axis is a bearing which keeps tension on each
  32                 belt (these are called the "idler ends").
  33
  34                 The entire X-axis assembly is moved along the Z-axis (up and down) by
  35                 two separate (but identically controlled) motors.  The Z-axis is not
  36                 belt driven but rather uses screws (generally M5 threaded rods) which
  37                 turn against a fixed nut at each end of the X-axis to provide
  38                 positioning.
  39
  40                 Limit switches located at one end or the other of each axis are used
  41                 by the printer firmware to "home" the extruder at the beginning of a
  42                 print.
  43
  44         1.3 Extruder
  45                 Plastic filament is extruded onto the print surface by a geared extruder
  46                 mounted to the X-axis carriage.  A fifth stepper motor turns a grooved
  47                 bolt (i.e. a hobbed bolt) against which the filament is held firmly by
  48                 a spring-mounted bearing.  The filament is forced through a heated end
  49                 with a tiny hole (generally 0.5mm or smaller) at a controlled pace to
  50                 construct the desired object.  A thermistor located at the hot end is
  51                 monitored to maintain the programmed extrusion temperature, which is
  52                 material dependent but generally around 200 degrees Celsius.
  53
  54 2. Assemble the Y axis (part 1)
  55
  56 2.1     The following parts are used during this step:
  57         a. The two M10 threaded rods
  58         b. The Y axis smooth rods
  59         c. The plastic Y end pieces (2)
  60         d. The two plastic frame brace supports
  61         e. 12 M10 nuts and washers
  62         f. Four linear bearings (LM8UU)
  63
  64 3. Assemble the Frame (part 1)
  65
  66 3.1     The following parts are used during this step:
  67         a. The two side pieces of 2020 aluminum extrusion (the longer ones, generally)
  68         b. One of the two horizontal pieces of 2020 aluminum extrusion (the shorter
  69            ones, generally)
  70         c. 36 T-slot nuts
  71         d. 28 M5 x 8mm screws
  72         e. The plastic Z motor holders (2)
  73         f. The plastic rear frame brackets (2)
  74
  75 4. Mount the Y axis to the frame
  76
  77 4.1     The following parts are used during this step:
  78         a. The partially-assembled Y axis from step 2.
  79         b. The partially assembled frame from step 3.
  80         c. Eight M5 x 8mm screws
  81
  82
  83 5. Assemble the X axis (part 1)
  84
  85 5.1     The following parts are used during this step:
  86         a. The two plastic X end pieces ("motor" and "idler")
  87         b. Eight linear bearings (LM8UU)
  88         c. The two X axis smooth rods
  89
  90 6. Mounting the X axis to the Z axis
  91
  92 7. Assemble the Frame (part 2)
  93
  94
  95