10. squeeze ball even tighter

[challenge-bot] / 3d-printables / caster-standoff.scad

diff --git a/3d-printables/caster-standoff.scad b/3d-printables/caster-standoff.scad
index dae0ccfbd147973e5abe9476559a02bc3adb08ef..cf7be337620a2fa9eb88859cfcac1ce961c0398f 100644 (file)
--- a/3d-printables/caster-standoff.scad
+++ b/3d-printables/caster-standoff.scad
@@ -7,7 +7,17 @@
 // use 10 ish for development, 60 or so for printing
 $fn = 60;
 
-standoff_radius = 14.732 / 2; // 0.580 / 2 inches from spec sheet
+/* measured with calipers */
+ball_diameter = 12.7 + 1;
+ball_radius = ball_diameter / 2;
+
+wall_thickness = 1;
+holder_height = (25 / 32) * ball_diameter + wall_thickness;
+
+holder_radius = ball_radius + wall_thickness;
+holder_diameter = holder_radius * 2;
+
+standoff_radius = holder_radius; // 0.580 / 2 inches from spec sheet
 standoff_height = 48; // eyeballed
 
 // eyeballed caster flange height, (0.580/5) inches, times 2 to be stronger
@@ -44,35 +54,25 @@ module deck_flange_reinforcement(){
                 deck_flange_height * 1.1, // 1.1 is bigger than 1
                 deck_flange_radius]);}}}}}
 
-module caster_standoff(){
-  cylinder(h = standoff_height - caster_flange_height,
-           r = standoff_radius);
-  deck_flange();
-  for(ii = [0:3]){
-    rotate([0, 0, 45 + 90 * ii])
-      deck_flange_reinforcement();}
-  caster_deck_interlock_solid();}
-
 module ball_holder(){
-  /* measured with calipers */
-  ball_diameter = 12.7 + 0.5;
-  ball_radius = ball_diameter / 2;
-
-  wall_thickness = 1.5;
-  holder_height = ball_radius + wall_thickness * 2;
-
-  holder_outer_radius = ball_radius + wall_thickness;
-  holder_outer_diameter = holder_outer_radius * 2;
-
+  gap = wall_thickness * 4;
   difference (){
-    cylinder(r = holder_outer_radius, h = holder_height);
+    cylinder(r = holder_radius, h = holder_height);
     translate([0, 0, ball_radius + wall_thickness]){
       sphere(r = ball_radius);}
     translate([0, 0, holder_height / 2 + wall_thickness]){
-      cube([holder_outer_diameter + 0.1,
-            wall_thickness * 2,
-            holder_height],
+      cube([holder_diameter + 0.1, gap, holder_height],
            center = true);}}}
 
-ball_holder();
+module caster_standoff(){
+  cylinder(h = standoff_height,
+           r = standoff_radius);
+  deck_flange();
+  for(ii = [0:3]){
+    rotate([0, 0, 45 + 90 * ii])
+      deck_flange_reinforcement();}
+  translate([0, 0, standoff_height]){
+    ball_holder();}}
+
 //caster_standoff();
+ball_holder();