use global fragment number for caster standoff

[challenge-bot] / caster-standoff.scad

diff --git a/caster-standoff.scad b/caster-standoff.scad
index 27d2ba6c351fcef22e8e9a3cf7295b7210c01509..c9d60d96ddda70f2529ad352e313d4b3e47f90a9 100644 (file)
--- a/caster-standoff.scad
+++ b/caster-standoff.scad
@@ -4,6 +4,9 @@
 // https://gitorious.org/ozzloy/challenge-bot
 // https://github.com/waynegramlich/challenge-bot
 
+// use 10 ish for development, 100 or so for printing
+$fn = 10;
+
 standoff_radius = 14.732 / 2; // 0.580 / 2 inches from spec sheet
 standoff_height = 55; // eyeballed
 
@@ -11,7 +14,7 @@ nut_short_side = 4.7; // from calipers
 nut_height = 1.6; // from calipers
 
 // eyeballed caster flange height, (0.580/5) inches, times 2 to be stronger
-caster_flange_height = 2.9464;
+caster_flange_height = 5;
 caster_flange_width = 20.32;  // 0.800 inches
 caster_flange_screw_radius = 2.286 / 2;  // 0.090 inches
 caster_flange_screw_length = 8; // eyeballed
@@ -19,21 +22,18 @@ caster_flange_screw_length = 8; // eyeballed
 deck_grid_width = 25.4; // measured center to center on grid on pegboard
 deck_flange_height = 2.9464;
 deck_flange_screw_radius = 3.556 / 2;  // For #6 machine screws
-deck_flange_radius = deck_grid_width * 1.22;
+deck_flange_radius = (deck_grid_width) / 2 + deck_flange_screw_radius + 3;
 
 module deck_flange(){
   difference(){
     cylinder(h = deck_flange_height, r = deck_flange_radius);
     for(ii = [-1, 1]){
-      translate([deck_grid_width * ii, 0, -.1])
+      translate([deck_grid_width / 2 * ii, 0, -.1])
         cylinder(h = deck_flange_height * 1.1,
-                 r = deck_flange_screw_radius,
-                 $fn = 20);}
-    for(ii = [-1, 1]){
-      translate([0, deck_grid_width * ii, -.1])
+                 r = deck_flange_screw_radius);
+      translate([0, deck_grid_width / 2 * ii, -.1])
         cylinder(h = deck_flange_height * 1.1,
-                 r = deck_flange_screw_radius,
-                 $fn = 20);}}}
+        r = deck_flange_screw_radius);}}}
 
 module deck_flange_reinforcement(){
   translate([-deck_flange_radius,
@@ -50,12 +50,10 @@ module deck_flange_reinforcement(){
 module caster_flange_screws(){
   translate([standoff_radius, 0, 0])
     cylinder(h = caster_flange_screw_length,
-             r = caster_flange_screw_radius,
-             $fn = 20);
+             r = caster_flange_screw_radius);
   translate([-standoff_radius, 0, 0])
     cylinder(h = caster_flange_screw_length,
-             r = caster_flange_screw_radius,
-             $fn = 20);}
+             r = caster_flange_screw_radius);}
 
 module caster_flange(){
   side_radius = caster_flange_width / 2 - standoff_radius;
@@ -72,45 +70,51 @@ module nut(size, height){
 
 module nuts(){
   translate([standoff_radius, 0, nut_height/2])
-    nut(nut_short_side, nut_height);
+    nut(nut_short_side, nut_height + .1);
   translate([-standoff_radius, 0, nut_height/2])
-    nut(nut_short_side, nut_height);}
+    nut(nut_short_side, nut_height + .1);}
+
+module _2_screw (){
+  //measured with calipers
+  screw_length = 8;
+  thread_radius = 2.17 / 2 - 0.1; // subtract 0.1 to make squeeze fit
+  head_height = 1.8;
+  head_radius = 4.1 / 2;
+  cylinder(r = thread_radius, h = screw_length);
+  cylinder(r = head_radius, h = head_height);}
 
-module caster_standoff(){
+module caster_standoff_deck_side(){
   difference(){
-    union(){
-      cylinder(h = standoff_height, r = standoff_radius);
-      translate([0, 0, standoff_height - caster_flange_height])
-        caster_flange();}
+    cylinder(h = standoff_height - caster_flange_height,
+             r = standoff_radius);
     translate([0, 0, standoff_height - caster_flange_screw_length * 1.1 + 0.1])
       scale([1, 1, 1.1])
         caster_flange_screws();
     translate([0, 0, standoff_height - (caster_flange_height + nut_height)])
-      nuts();}
+      nuts();
+    translate([0, 0, standoff_height]){
+      // make hole to get to screw head depth
+      cylinder(r = 4.1 / 2, h = 3, center = true);
+      translate([0, 0, -0.7])
+        rotate([180, 0, 0])
+          _2_screw(r = 0.5, h = 5);}}
   deck_flange();
   for(ii = [0:3]){
     rotate([0, 0, 45 + 90 * ii])
       deck_flange_reinforcement();}}
 
-module caster_top_half(){
-  difference(){
-    caster_standoff();
-    cylinder(r1 = deck_flange_radius * 4 / 3,
-             r2 = 0,
-             h = standoff_height * 3 / 4);}}
-
-module caster_bottom_half (){
+module caster_standoff_caster_side(){
   difference(){
-    intersection (){
-      caster_standoff();
-      cylinder(r1 = deck_flange_radius * 4 / 3,
-                    r2 = 0,
-                    h = standoff_height * 3 / 4);}
-    // leave a little room for glue
-    translate([0, 0, standoff_height * 3 / 4 - 1]) cylinder(r = 2, h = 2);}}
+    caster_flange();
+    translate([0, 0, caster_flange_height - 0.7]){
+      rotate([180, 0, 0]){
+        _2_screw();}}
+    // make hole to get to screw head
+    translate([0, 0, caster_flange_height - 0.8]){
+      cylinder(r = 4.1 / 2, h = 10);}
+    translate([0, 0, -.1]){
+      caster_flange_screws();}}}
 
-// move the top half and flip it over for printing
-translate([0, deck_flange_radius + standoff_radius + 1, standoff_height]){
-  rotate([0, 180, 0]){
-    caster_top_half();}}
-caster_bottom_half();
+caster_standoff_deck_side();
+translate([caster_flange_width / 2 + deck_flange_radius + 1, 0, 0]){
+  caster_standoff_caster_side();}