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 // todo: make x-end height global and make anything relying implicitly
  12 // on the height of the x-end use that for positioning.
  13
  14 // bearing height, strain relief (&& maybe make dependent upon the bearing diameter)
  15
  16 // major issues with rev 3
  17
  18 // - motor side screw hole conflicts with switch / other rear mount is
  19 //   inaccessible without removing the leadscrew from the nut
  20
  21 // - New idler anti-pitching ribs are too big (new idler I wasn't
  22 //   using is larger so the existing ones worked fine for that one...)
  23 //   NOTE: new idler is meant for integrated toothed idler...
  24
  25 use <bushing.scad>
  26 include <configuration.scad>
  27
  28 pushfit_d = bushing_xy[0] * 2 + 0.25;
  29 thinwall = single_wall_width * 6; // 3 perimeters
  30 vertical_bushing_base_size = bushing_z[1]*2 + 2 * thinwall;
  31
  32 x_box_length = 45; // TODO: auto-adjust based on bearing size?
  33
  34 module vertical_bushing_base(){
  35      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);
  36      cylinder(h = x_box_height, r=vertical_bushing_base_size/2, $fn = 90);
  37 }
  38
  39 module vertical_bushing_holes(){
  40   // FIXME: is extra cut necessary? check conf_bushing
  41   bushing_cut_extra = 0.2; // padding so it's not too tight
  42   translate(v=[0,0,-4]) cylinder(h = x_box_height + 3, r=bushing_z[1] + bushing_cut_extra, $fn = 60);
  43   translate(v=[0,0,x_box_height-4]) cylinder(h=x_box_height,r=bushing_z[1]-1,$fn=60);
  44   // TODO: is slit too wide or too low? Wilson increased width from 1
  45   // -> 2 mm, slit also might need to end 1-2mm before the base
  46   #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);
  47   translate([0,0,-1]) cylinder(h=9,r1=bushing_z[1]+thinwall/2+1,r2=4,$fn=60);
  48 }
  49
  50
  51 module nut_trap_base () {
  52      // TODO: cube doesn't line up with edge of base, cylinder is slightly asymmetrical
  53      // adapt newer nut trap from prusa i3 mk3 instead of wilson2
  54      cube(size=[16,21,8],center=true);
  55      translate ([2,0,0]) cylinder(h=8,r=12.5,$fn=50,center=true);
  56 }
  57
  58 module nut_trap () {
  59      union() {
  60                // center post of brass nut
  61                    cylinder(h=12,r=5.45,$fn=50,center=true);
  62                    // holes for m3 screws in brass nut
  63                    translate(v=[8,0,0]) cylinder(h=12,r=1.8,$fn=20,center=true);
  64                    #rotate([0,0,90]) translate(v=[8,0,0]) cylinder(h=12,r=1.8,$fn=20,center=true);
  65                    rotate([0,0,180]) translate(v=[8,0,0]) cylinder(h=12,r=1.8,$fn=20,center=true);
  66                    #rotate([0,0,270]) translate(v=[8,0,0]) cylinder(h=12,r=1.8,$fn=20,center=true);
  67      }
  68 }
  69
  70 // x position of edge of main block (facing frame), for attaching objects to it
  71 function x_base_back() = -10 - bushing_xy[0] - x_box_width/2;
  72 // y position of edge of main block facing away from x-axis
  73 function x_base_outside() = vertical_bushing_base_size/2;
  74 // y position of edge of main block facing toward the x-axis
  75 function x_base_inside() = -x_box_length/2 - vertical_bushing_base_size/2;
  76
  77 module x_end_base(){
  78 // Main block
  79 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);
  80 // Bearing holder
  81  vertical_bushing_base();
  82 //Nut trap
  83  translate(v=[-4+zmotor_delta_x,-17-zmotor_delta_y,4]) nut_trap_base ();
  84 }
  85
  86 // TODO: x translation of belt and smooth rods needs to adapt to
  87 // x_end_width and motor/idler pulley position.
  88
  89 module x_end_holes(){
  90  vertical_bushing_holes();
  91  // Belt hole
  92  translate(v=[-1,0,0]){
  93  // Stress relief
  94  translate(v=[-5.5-10+1.5,-bushing_z[1]-4,30]) cube(size = [20,1,28], center = true);
  95  // Cut out for belt (this is NOT centered because the motor isn't centered)
  96  x_box_offset = -x_box_length/2 + vertical_bushing_base_size/2;
  97  difference(){
  98         translate(v=[-5.5-10+1.5, x_box_offset ,30]) cube(size = [10, x_box_length + 1,28], center = true);
  99
 100         // Nice edges
 101         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);
 102         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);
 103         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);
 104         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);
 105
 106  }
 107 }
 108
 109  // FIXME: z rod placement isn't consistent with carriage
 110  pushrod_extra_z = 2.5;
 111
 112  // FIXME: confirm length of smooth rod doesn't change when x_box_length or bearing size changes
 113  // should also make sure this is long enough if x-ends somehow end up larger than 50mm
 114  //Bottom pushfit rod
 115  #translate(v=[-15,-41.5,bushing_xy[0]+pushrod_extra_z]) rotate(a=[-90,0,0]) pushfit_rod(pushfit_d,50);
 116  // Top pushfit rod
 117  translate(v=[-15,-41.5,xaxis_rod_distance+bushing_xy[0]+pushrod_extra_z]) rotate(a=[-90,0,0]) pushfit_rod(pushfit_d,50);
 118
 119 // Nut trap
 120  translate(v=[zmotor_delta_x,-17-zmotor_delta_y,3]) rotate ([0, 0, 45]) nut_trap ();
 121 }
 122
 123
 124 // Final prototype
 125 module x_end_plain(){
 126  difference(){
 127   x_end_base();
 128   x_end_holes();
 129  }
 130 }
 131
 132 x_end_plain();
 133
 134
 135 module pushfit_rod(diameter,length){
 136  translate([0,-0.3,0])  cylinder(h = length, r=diameter/2, $fn=30);
 137  translate([0,0.3,0])  cylinder(h = length, r=diameter/2, $fn=30);
 138  // TODO: reintroduce teardrop holes?
 139 // difference(){
 140 //      translate(v=[0,-diameter/2.85,length/2]) rotate([0,0,45]) cube(size = [diameter/2,diameter/2,length], center = true);
 141 //      translate(v=[0,-diameter/4-diameter/2-0.4,length/2]) rotate([0,0,0]) cube(size = [diameter,diameter/2,length], center = true);
 142 // }
 143
 144 }