chiark / gitweb /
belt-slot-cut-jig: round off the corners of the holder
[reprap-play.git] / belt-slot-cut-jig.scad
index c613c8f45358e0445cd82391a0ea63ea5415c517..cca4e27647b69a3ea63cbcab047ffeeb6c786ff7 100644 (file)
@@ -8,7 +8,7 @@
 crewpunch_slop = 0.3;
 
 holder_min_wall = 2;
-holder_attach_near_wall = 3;
+holder_attach_near_wall = 5;
 
 holder_attach_xsz = 5;
 holder_ctie_width = 4.0 + 0.5;
@@ -16,6 +16,8 @@ holder_ctie_thick = 3.0 + 0.5;
 holder_attach_walls = 3;
 holder_attach_roof = 2.5;
 
+holder_corner_round = 2.0;
+
 jig_interval = 25;
 strap_width = 26.75 + 0.7;
 strap_thick = 3;
@@ -54,31 +56,42 @@ crewpunch_shaft_max_y = 7.5;
 
 crewpunch_systematic_size_error = +0.36;
 
-crewpunch_min_y = 4.7 - crewpunch_systematic_size_error;
-
 crewpunch_smallest_shape = crewpunch_shape[0];
 crewpunch_biggest_shape = crewpunch_shape[len(crewpunch_shape)-1];
 
-crewpunch_skew_angle = 2.0; //degrees
-crewpunch_skew_yoff = 0.6; //mm
+crewpunch_skew_angle = 3.5; //degrees
+crewpunch_skew_yoff = +1.1; //mm
 
 // computed
 
+punch_dx = 0.5 * (-crewpunch_biggest_shape[2][0]
+                 +crewpunch_biggest_shape[2][1]);
+punch_dy = 0.5 * (+crewpunch_biggest_shape[1][1]
+                 -crewpunch_biggest_shape[1][0]) + crewpunch_skew_yoff;
+
 attach_ysz = holder_attach_walls*2 + holder_ctie_width;
 
 holder_block_zsz = crewpunch_biggest_shape[0] - crewpunch_smallest_shape[0];
 holder_xsz = crewpunch_biggest_shape[2][0] + crewpunch_biggest_shape[2][1] +
   holder_min_wall*2;
 
-holder_front_all = crewpunch_shaft_max_y - crewpunch_biggest_shape[1][1]
-  + attach_ysz + crewpunch_systematic_size_error + crewpunch_skew_yoff
-  + holder_xsz/2 * sin(abs(crewpunch_skew_angle));
+holder_skewangle_yextra = holder_xsz/2 * sin(abs(crewpunch_skew_angle));
+
+holder_max_y = punch_dy + crewpunch_biggest_shape[1][0] + holder_min_wall
+  + crewpunch_systematic_size_error + holder_skewangle_yextra;
+
+holder_attach_max_y = punch_dy
+  - max(crewpunch_biggest_shape[1][1], crewpunch_shaft_max_y)
+  - crewpunch_systematic_size_error - holder_skewangle_yextra;
+
+holder_block_min_y = punch_dy
+  - crewpunch_biggest_shape[1][1] - holder_attach_near_wall +
+  - crewpunch_systematic_size_error - holder_skewangle_yextra;
 
-crewpunch_biggest_y =
-  crewpunch_biggest_shape[1][0] + crewpunch_biggest_shape[1][1];
-holder_ysz = crewpunch_biggest_y + holder_min_wall + holder_front_all;
+holder_all_min_y = holder_attach_max_y - attach_ysz;
 
-attach_offset = 0.5 * (holder_front_all - holder_attach_near_wall);
+jig_max_y = max(holder_max_y + main_slop, strap_width/2) + edgewall_width;
+jig_min_y = min(holder_all_min_y - main_slop, -strap_width/2) - edgewall_width;
 
 jig_main_zsz = holder_block_zsz + punch_travel;
 
@@ -100,7 +113,7 @@ module CrewPunch(){
            mirror([xind?1:0,0,0]) mirror([0,yind?0:1,0]){
              translate([-0.1,-0.1,-0.1])
                cube([0.1 + layer[2][xind] + ourslop,
-                     0.1 + layer[1][yind] + ourslop,
+                     0.1 + layer[1][1-yind] + ourslop,
                      0.2]);
            }
       }
@@ -108,37 +121,49 @@ module CrewPunch(){
   }
 }
 
+module MaybeRoundedCube(sizes, roundedness){
+  if (roundedness > 0) {
+    translate([roundedness, roundedness, 0]){
+      minkowski(){
+       cube([sizes[0] - roundedness*2,
+             sizes[1] - roundedness*2,
+             sizes[2]]);
+       cylinder(h=0.05, r=roundedness, $fn=20);
+      }
+    }
+  } else {
+    cube(sizes);
+  }
+}
+
 module PunchHolder(cutouts=true){
-  translations=[-holder_xsz/2,
-               -holder_ysz + holder_min_wall + crewpunch_biggest_y/2,
-               0];
-  translate(translations){
+  roundedness = cutouts ? holder_corner_round : 0;
     difference(){
-      translate([0,attach_offset,0])
-       cube([holder_xsz, holder_ysz - attach_offset, holder_block_zsz]);
+      translate([-holder_xsz/2, holder_block_min_y, 0])
+       MaybeRoundedCube([holder_xsz,
+                         holder_max_y - holder_block_min_y,
+                         holder_block_zsz],
+                        roundedness);
       if (cutouts)
-       translate([0,-crewpunch_skew_yoff])
-       translate(-translations)
        rotate([0,0,-crewpunch_skew_angle])
-       translate(translations)
-       translate([crewpunch_biggest_shape[2][1] + holder_min_wall,
-                  crewpunch_biggest_shape[1][0] + holder_front_all,
+       translate([punch_dx,
+                  punch_dy,
                   -crewpunch_smallest_shape[0]])
          CrewPunch();
     }
     difference(){
-      translate([holder_xsz/2 - holder_attach_xsz/2, 0, 0])
-       cube([holder_attach_xsz,
-             attach_ysz,
-             holder_block_zsz + punch_travel
-             + holder_ctie_thick + holder_attach_roof + 1]);
+      translate([-holder_attach_xsz/2, holder_all_min_y, 0])
+       MaybeRoundedCube([holder_attach_xsz,
+                         attach_ysz,
+                         holder_block_zsz + punch_travel
+                         + holder_ctie_thick + holder_attach_roof + 1],
+                        roundedness);
       if (cutouts)
        translate([-30,
-                  holder_attach_walls,
+                  holder_all_min_y + holder_attach_walls,
                   holder_block_zsz + punch_travel])
          cube([60, holder_ctie_width, holder_ctie_thick]);
     }
-  }
 }
 
 module RegistrationGroove(l){
@@ -155,10 +180,10 @@ module RegistrationGroove(l){
 module OneJig(){
   difference(){
     translate([-(jig_interval/2 + jig_overlap),
-              -(strap_width/2 + edgewall_width) - attach_offset,
+              jig_min_y,
               -strap_thick])
       cube([jig_interval + 2,
-           strap_width + edgewall_width*2 + attach_offset,
+           jig_max_y - jig_min_y,
            jig_main_zsz + strap_thick]);
     minkowski(){
       cube([main_slop*2, main_slop*2, 50], center=true);
@@ -214,7 +239,8 @@ module Jig(){
 }
 
 module JigT(){ ////toplevel
-  translate([0,0,jig_main_zsz])
+  rotate([0,0,-45])
+    translate([0,0,jig_main_zsz])
     rotate([180,0,0])
     Jig();
 }
@@ -223,16 +249,16 @@ module PunchHolderT(){ ////toplevel
   PunchHolder(true);
 }
 
-module Demo(){
+module Demo(){ ////toplevel
   %PunchHolder();
   Jig();
 }
 
 module Kit(){ ////toplevel
+  JigT();
   rotate([0,0,-45]){
-    JigT();
     translate([(jig_iters-1)*jig_interval/2,
-              -strap_width,
+              jig_min_y - holder_max_y - 5,
               0])
       PunchHolder();
   }