box_frame/x-end.scad

   1 // PRUSA iteration3
   2 // X end prototype
   3 // GNU GPL v3
   4 // Josef Průša <iam@josefprusa.cz> and contributors
   5 // http://www.reprap.org/wiki/Prusa_Mendel
   6 // http://prusamendel.org
   7
   8 // Also includes code from Wilson and Wilson2, (c) Marty Rice
   9 // https://github.com/mjrice/wilson
  10
  11 // major issues with rev 3
  12
  13 // - motor side screw hole conflicts with switch / other rear mount is
  14 //   inaccessible without removing the leadscrew from the nut
  15
  16 use <bushing.scad>
  17 include <configuration.scad>
  18
  19 pushfit_d = bushing_xy[0] * 2 + 0.2;
  20 thinwall = single_wall_width * 6; // 3 perimeters
  21 vertical_bushing_base_size = bushing_z[1]*2 + 2 * thinwall;
  22
  23 x_box_length = 45; // TODO: auto-adjust based on bearing size?
  24
  25 // todo: add ghost bearing model to make it easier to spot check if
  26 // everything is aligned
  27 module vertical_bushing_base(){
  28      translate(v=[-2-vertical_bushing_base_size/4,0,x_box_height/2]) cube(size = [4+vertical_bushing_base_size/2,vertical_bushing_base_size,x_box_height], center = true);
  29      cylinder(h = x_box_height, r=vertical_bushing_base_size/2, $fn = 90);
  30 }
  31
  32 module vertical_bushing_holes(){
  33   // FIXME: is extra cut necessary? check conf_bushing
  34   bushing_cut_extra = 0.2; // padding so it's not too tight
  35   translate(v=[0,0,-4]) cylinder(h = x_box_height + 3, r=bushing_z[1] + bushing_cut_extra, $fn = 60);
  36   translate(v=[0,0,x_box_height-4]) cylinder(h=x_box_height,r=bushing_z[1]-1,$fn=60);
  37   // TODO: is slit too wide or too low? Wilson increased width from 1
  38   // -> 2 mm, slit also might need to end 1-2mm before the base
  39   #rotate(a=[0,0,-50]) translate(v=[thinwall*2 + 1,0,x_box_height/2 - 2]) cube(size = [bushing_z[2]/2, 2 ,x_box_height], center = true);
  40   translate([0,0,-1]) cylinder(h=9,r1=bushing_z[1]+thinwall/2+1,r2=4,$fn=60);
  41 }
  42
  43 module nut_trap_base () {
  44      // TODO: cube doesn't line up with edge of base, cylinder is slightly asymmetrical
  45      // adapt newer nut trap from prusa i3 mk3 instead of wilson2
  46      cube(size=[16,21,8],center=true);
  47      translate ([2,0,0]) cylinder(h=8,r=12.5,$fn=50,center=true);
  48 }
  49
  50 module nut_trap () {
  51      union() {
  52                // center post of brass nut
  53                    cylinder(h=12,r=5.45,$fn=50,center=true);
  54                    // holes for m3 screws in brass nut
  55                    translate(v=[8,0,0]) cylinder(h=12,r=1.8,$fn=20,center=true);
  56                    #rotate([0,0,90]) translate(v=[8,0,0]) cylinder(h=12,r=1.8,$fn=20,center=true);
  57                    rotate([0,0,180]) translate(v=[8,0,0]) cylinder(h=12,r=1.8,$fn=20,center=true);
  58                    #rotate([0,0,270]) translate(v=[8,0,0]) cylinder(h=12,r=1.8,$fn=20,center=true);
  59      }
  60 }
  61
  62 // x position of edge of main block (facing frame), for attaching objects to it
  63 function x_base_back() = -10 - bushing_xy[0] - x_box_width/2;
  64 // y position of edge of main block facing away from x-axis
  65 function x_base_outside() = vertical_bushing_base_size/2;
  66 // y position of edge of main block facing toward the x-axis
  67 function x_base_inside() = -x_box_length/2 - vertical_bushing_base_size/2;
  68
  69 module x_end_base(){
  70 // Main block
  71 translate(v=[-10 - bushing_xy[0], -x_box_length/2 + vertical_bushing_base_size/2,x_box_height/2]) cube(size = [x_box_width,x_box_length,x_box_height], center = true);
  72 // Bearing holder
  73  vertical_bushing_base();
  74 //Nut trap
  75  translate(v=[-4+zmotor_delta_x,-17-zmotor_delta_y,4]) nut_trap_base ();
  76 }
  77
  78 // TODO: x translation of belt and smooth rods needs to adapt to
  79 // x_end_width and motor/idler pulley position.
  80
  81 module x_end_holes(){
  82  vertical_bushing_holes();
  83  // Belt hole
  84  translate(v=[-1,0,0]){
  85  // Stress relief
  86  translate(v=[-5.5-10+1.5,-bushing_z[1]-4,30]) cube(size = [20,1,28], center = true);
  87  // Cut out for belt (this is NOT centered because the motor isn't centered)
  88  x_box_offset = -x_box_length/2 + vertical_bushing_base_size/2;
  89  difference(){
  90         translate(v=[-5.5-10+1.5, x_box_offset ,30]) cube(size = [10, x_box_length + 1,28], center = true);
  91
  92         // Nice edges
  93         translate(v=[-5.5-10+1.5,x_box_offset,30+23]) rotate([0,45,0]) cube(size = [10,x_box_length + 1,28], center = true);
  94         translate(v=[-5.5-10+1.5,x_box_offset,30+23]) rotate([0,-45,0]) cube(size = [10,x_box_length + 1,28], center = true);
  95         translate(v=[-5.5-10+1.5,x_box_offset,30-23]) rotate([0,45,0]) cube(size = [10,x_box_length + 1,28], center = true);
  96         translate(v=[-5.5-10+1.5,x_box_offset,30-23]) rotate([0,-45,0]) cube(size = [10,x_box_length + 1,28], center = true);
  97
  98  }
  99 }
 100
 101
 102  // FIXME: confirm length of smooth rod doesn't change when x_box_length or bearing size changes
 103  // should also make sure this is long enough if x-ends somehow end up larger than 50mm
 104  // TODO: needs to shift top rod as diameter increases, wall is very
 105  // thing for 10mm, and fails entirely for 12mm
 106  translate([-10 - bushing_xy[0], 0, 0]) {
 107       // Top pushfit rod
 108       #translate([0, -41.5, 6]) rotate([-90, 0, 0]) pushfit_rod(pushfit_d, 50);
 109       // Bottom pushfit rod
 110       translate([0, -41.5, xaxis_rod_distance+6]) rotate([-90, 0, 0]) pushfit_rod(pushfit_d, 50);
 111  }
 112
 113 // Nut trap
 114  translate(v=[zmotor_delta_x,-17-zmotor_delta_y,3]) rotate ([0, 0, 45]) nut_trap ();
 115 }
 116
 117
 118 // Final prototype
 119 module x_end_plain(){
 120  difference(){
 121   x_end_base();
 122   x_end_holes();
 123  }
 124 }
 125
 126 x_end_plain();
 127
 128
 129 module pushfit_rod(diameter,length){
 130  translate([0,-0.3,0])  cylinder(h = length, r=diameter/2, $fn=30);
 131  translate([0,0.3,0])  cylinder(h = length, r=diameter/2, $fn=30);
 132  // TODO: reintroduce teardrop holes?
 133 // difference(){
 134 //      translate(v=[0,-diameter/2.85,length/2]) rotate([0,0,45]) cube(size = [diameter/2,diameter/2,length], center = true);
 135 //      translate(v=[0,-diameter/4-diameter/2-0.4,length/2]) rotate([0,0,0]) cube(size = [diameter,diameter/2,length], center = true);
 136 // }
 137
 138 }