belt-slot-cut-jig.scad

   1 // -*- C -*-
   2
   3 // todo
   4 //  various registration marks
   5 //   protrustions at ends at strap width and middle
   6 //   grooves on top face at 1/4,1/2,3/4 length and 1/2 width
   7
   8 crewpunch_slop = 0.3;
   9
  10 holder_min_wall = 2;
  11 holder_attach_near_wall = 3;
  12
  13 holder_attach_xsz = 5;
  14 holder_ctie_width = 4.0 + 0.5;
  15 holder_ctie_thick = 2.0 + 0.5;
  16 holder_attach_walls = 3;
  17 holder_attach_roof = 2.5;
  18
  19 jig_interval = 25;
  20 strap_width = 25;
  21 strap_thick = 3;
  22 edgewall_width = 3;
  23
  24 punch_travel = 8;
  25
  26 main_slop = 0.5;
  27
  28 jig_max_len = 160; // print diagonally
  29 //jig_max_len = 30;
  30
  31 registrationgroove_width = 0.8;
  32 registrationgroove_depth = 1.2;
  33
  34 registrationprotrusion_poke = 3;
  35 registrationprotrusion_slope = 0.75;
  36
  37 jig_overlap = 1;
  38
  39 // from careful measurement
  40
  41 crewpunch_shape =
  42   [[  6, [0.6, 6.0], [1.6, 12.3] ],
  43    [  8, [1.1, 6.2], [1.9, 12.5] ],
  44    [ 10, [1.6, 6.5], [2.1, 12.8] ],
  45    [ 12, [1.8, 6.6], [2.3, 12.7] ],
  46    [ 14, [2.1, 6.8], [2.6, 13.0] ],
  47    [ 16, [2.4, 6.9], [2.7, 13.2] ]];
  48
  49 crewpunch_shaft_max_y = 7.5;
  50
  51 crewpunch_systematic_size_error = +0.36;
  52
  53 crewpunch_min_y = 4.7 - crewpunch_systematic_size_error;
  54
  55 crewpunch_smallest_shape = crewpunch_shape[0];
  56 crewpunch_biggest_shape = crewpunch_shape[len(crewpunch_shape)-1];
  57
  58 // computed
  59
  60 attach_ysz = holder_attach_walls*2 + holder_ctie_width;
  61 holder_front_all = crewpunch_shaft_max_y - crewpunch_biggest_shape[1][1]
  62   + attach_ysz;
  63
  64 holder_block_zsz = crewpunch_biggest_shape[0] - crewpunch_smallest_shape[0];
  65 holder_xsz = crewpunch_biggest_shape[2][0] + crewpunch_biggest_shape[2][1] +
  66   holder_min_wall*2;
  67 crewpunch_biggest_y =
  68   crewpunch_biggest_shape[1][0] + crewpunch_biggest_shape[1][1];
  69 holder_ysz = crewpunch_biggest_y + holder_min_wall + holder_front_all;
  70
  71 attach_offset = 0.5 * (holder_front_all - holder_attach_near_wall);
  72
  73 jig_main_zsz = holder_block_zsz + punch_travel;
  74
  75 jig_ends_extra = 2;
  76
  77 //jig_iters = (jig_max_len - jig_ends_extra) / jig_interval;
  78 jig_iters=2;
  79 echo(jig_iters);
  80
  81 // objects
  82
  83 module CrewPunch(){
  84   ourslop = crewpunch_slop - crewpunch_systematic_size_error;
  85   hull(){
  86     for(layer=crewpunch_shape){
  87       translate([0,0, layer[0]]){
  88         for(xind=[0,1]) //translate([xind?0:1,0,0])
  89           for(yind=[0,1]) //translate([0,yind?0.5:0,0])
  90             mirror([xind?1:0,0,0]) mirror([0,yind?0:1,0]){
  91               translate([-0.1,-0.1,-0.1])
  92                 cube([0.1 + layer[2][xind] + ourslop,
  93                       0.1 + layer[1][yind] + ourslop,
  94                       0.2]);
  95             }
  96       }
  97     }
  98   }
  99 }
 100
 101 module PunchHolder(cutouts=true){
 102   translate([-holder_xsz/2,
 103              -holder_ysz + holder_min_wall + crewpunch_biggest_y/2,
 104              0]){
 105     difference(){
 106       translate([0,attach_offset,0])
 107         cube([holder_xsz, holder_ysz - attach_offset, holder_block_zsz]);
 108       if (cutouts)
 109         translate([crewpunch_biggest_shape[2][1] + holder_min_wall,
 110                    crewpunch_biggest_shape[1][0] + holder_front_all,
 111                    -crewpunch_smallest_shape[0]])
 112           CrewPunch();
 113     }
 114     difference(){
 115       translate([holder_xsz/2 - holder_attach_xsz/2, 0, 0])
 116         cube([holder_attach_xsz,
 117               attach_ysz,
 118               holder_block_zsz + punch_travel
 119               + holder_ctie_thick + holder_attach_roof + 1]);
 120       if (cutouts)
 121         translate([-30,
 122                    holder_attach_walls,
 123                    holder_block_zsz + punch_travel])
 124           cube([60, holder_ctie_width, holder_ctie_thick]);
 125     }
 126   }
 127 }
 128
 129 module RegistrationGroove(l){
 130   // runs along the +ve X axis for length l but at correct z pos
 131   translate([0, 0, jig_main_zsz + 0.1]) {
 132     rotate([90,0,90])
 133       linear_extrude(height=l)
 134       polygon([[-registrationgroove_width/2, 0],
 135                [ +registrationgroove_width/2, 0],
 136                [ 0, -registrationgroove_depth ]]);
 137   }
 138 }
 139
 140 module OneJig(){
 141   difference(){
 142     translate([-(jig_interval/2 + jig_overlap),
 143                -(strap_width/2 + edgewall_width) - attach_offset,
 144                -strap_thick])
 145       cube([jig_interval + 2,
 146             strap_width + edgewall_width*2 + attach_offset,
 147             jig_main_zsz + strap_thick]);
 148     minkowski(){
 149       cube([main_slop*2, main_slop*2, 50], center=true);
 150       PunchHolder(false);
 151     }
 152     translate([-100, -strap_width/2, -10])
 153       cube([200, strap_width, 10]);
 154    translate([-100,0,0])
 155      RegistrationGroove(200);
 156    for (xfrac=[-1/4,0,+1/4])
 157      translate([jig_interval * xfrac, -100, 0])
 158        rotate([0,0,90])
 159        RegistrationGroove(200);
 160   }
 161 }
 162
 163 module RegistrationProtrusion(){
 164   // points towards the positive x axis
 165   xsz = registrationprotrusion_poke;
 166   ysz = registrationprotrusion_poke;
 167   diag_sz = xsz * sqrt(2);
 168   zsz = diag_sz / registrationprotrusion_slope;
 169   hull(){
 170     translate([0, 0, 0.1]){
 171       linear_extrude(height=0.1)
 172         polygon([[   0, -ysz ],
 173                  [ xsz,    0 ],
 174                  [   0,  ysz ]]);
 175       translate([-0.1, 0, zsz ])
 176         rotate([0,0,45])
 177         cube(0.1);
 178     }
 179   }
 180 }
 181
 182 module Jig(){
 183   for(end=[0,1]){
 184     for(yfrac=[-1/2, 0, 1/2]){
 185       translate([ end
 186                   ? jig_interval * (jig_iters - 0.5)
 187                   : -jig_interval/2,
 188                  yfrac * strap_width,
 189                  0])
 190         rotate([0,0, end ? 0 : 180])
 191         translate([ jig_overlap, 0, 0 ])
 192         RegistrationProtrusion();
 193     }
 194   }
 195   for (i=[0:jig_iters-1]) {
 196     translate([jig_interval * i, 0, 0])
 197       OneJig();
 198   }
 199 }
 200
 201 module JigT(){ ////toplevel
 202   rotate([180,0,0])
 203     Jig();
 204 }
 205
 206 module PunchHolderT(){ ////toplevel
 207   PunchHolder(true);
 208 }
 209
 210 module Demo(){
 211   %PunchHolder();
 212   Jig();
 213 }
 214
 215 //CrewPunch();
 216 //PunchHolder();
 217 //PunchHolder(false);
 218 //OneJig();
 219 //Jig();
 220 //Demo();
 221 //JigT();
 222 //RegistrationProtrusion();
 223 //PunchHolderT();