tilt toward ball caster for stability on stops

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

diff --git a/3d-printables/caster-standoff.scad b/3d-printables/caster-standoff.scad
index 935a61db282f9acad0a86e26a5f0d9ae5157fc9f..6163b54f33798eb4931058a8ccafd5cf7a20e299 100644 (file)
--- a/3d-printables/caster-standoff.scad
+++ b/3d-printables/caster-standoff.scad
@@ -8,7 +8,7 @@
 $fn = 60;
 
 standoff_radius = 14.732 / 2; // 0.580 / 2 inches from spec sheet
-standoff_height = 55; // eyeballed
+standoff_height = 48; // eyeballed
 
 nut_short_side = 4.7; // from calipers
 nut_height = 1.6; // from calipers
@@ -74,15 +74,27 @@ module nuts(){
   translate([-standoff_radius, 0, nut_height/2])
     nut(nut_short_side, nut_height + .1);}
 
-module _2_screw (){
+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;
+  head_radius = 4.1 / 2 + 0.2; // add 0.2 to allow head to fit
   cylinder(r = thread_radius, h = screw_length);
   cylinder(r = head_radius, h = head_height);}
 
+module caster_deck_interlock_solid(){
+  translate([-1, standoff_radius - 2.1, 0]){
+    cube([2, 2, standoff_height]);}
+  translate([-1, -standoff_radius + 0.1, 0]){
+    cube([2, 2, standoff_height]);}}
+
+module caster_deck_interlock_hole(){
+  translate([0, standoff_radius - 1, -0.1]){
+    cube([2.5, 2.5, standoff_height], center = true);}
+  translate([0, -standoff_radius + 1, -0.1]){
+    cube([2.5, 2.5, standoff_height], center = true);}}
+
 module caster_standoff_deck_side(){
   difference(){
     cylinder(h = standoff_height - caster_flange_height,
@@ -94,14 +106,15 @@ module caster_standoff_deck_side(){
       nuts();
     translate([0, 0, standoff_height]){
       // make hole to get to screw head depth
-      cylinder(r = 4.1 / 2, h = 3, center = true);
+      cylinder(r = 4.1 / 2 + 0.2, 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();}}
+      deck_flange_reinforcement();}
+  caster_deck_interlock_solid();}
 
 module caster_standoff_caster_side(){
   difference(){
@@ -111,9 +124,10 @@ module caster_standoff_caster_side(){
         _2_screw();}}
     // make hole to get to screw head
     translate([0, 0, caster_flange_height - 0.8]){
-      cylinder(r = 4.1 / 2, h = 10);}
+      cylinder(r = 4.1 / 2 + 0.2, h = 10);}
     translate([0, 0, -.1]){
-      caster_flange_screws();}}}
+      caster_flange_screws();}
+    caster_deck_interlock_hole();}}
 
 caster_standoff_deck_side();
 translate([caster_flange_width / 2 + deck_flange_radius + 1, 0, 0]){