From 9e5a94b5f5e654ca686785056b697411c69f3092 Mon Sep 17 00:00:00 2001
From: Vitaliy Filippov <vitalif@yourcmc.ru>
Date: Tue, 29 Dec 2015 22:56:09 +0000
Subject: [PATCH] fix sizes & make customisable

---
 ball-amort/ball_amort.scad | 56 ++++++++++++++++++++------------------
 1 file changed, 30 insertions(+), 26 deletions(-)

diff --git a/ball-amort/ball_amort.scad b/ball-amort/ball_amort.scad
index cbc8ca7..945fa8c 100644
--- a/ball-amort/ball_amort.scad
+++ b/ball-amort/ball_amort.scad
@@ -1,47 +1,51 @@
 $fn = 50;
+tube_length = 4; // tube length in studs
+piston_length = 3; // piston length in studs
+travel_length = piston_length-2; // piston travel in studs
+
+travel = min(travel_length, piston_length-2, tube_length-2);
 
 //difference() { union() {
 
 difference() {
-  cylinder(r=4, h=4*8);
-  ball_end_n();
-  translate([0, 0, 6]) cylinder(r=3.2, h=4*8);
-  translate([-5, -0.5, 4*8-6]) cube(size=[10, 1, 3], center=false);
+  translate([0, 0, 2.3]) cylinder(r=4, h=tube_length*8-2.3);
+  translate([0, 0, 2.3]) ball_end_n();
+  translate([0, 0, 8]) cylinder(r=3.2, h=tube_length*8);
+  translate([-5, -0.5, tube_length*8-6]) cube(size=[10, 1, 3], center=false);
 }
 
-color([1, 0.5, 0.5]) translate([0, 0, 6*8]) rotate([180, 0, 0])
+color([1, 0.5, 0.5]) translate([0, 0, (tube_length+piston_length-1)*8]) rotate([180, 0, 0])
 {
   difference() {
-    union() {
-      cylinder(r=3, h=3*8);
-      cylinder(r=4, h=8);
+    translate([0, 0, 2.3]) union() {
+      cylinder(r=3, h=piston_length*8-2.3);
+      cylinder(r=4, h=8-2.3);
     }
-    translate([-5, -0.7, 14-3]) cube(size=[10, 1.4, 8+3], center=false);
-    ball_end_n();
+    translate([-5, -0.7, (piston_length-travel-1)*8+3]) cube(size=[10, 1.4, travel*8+3], center=false);
+    translate([0, 0, 2.3]) ball_end_n();
   }
 }
 
 //rotate([90, 0, 0])
-color([0.5, 0.5, 1]) translate([-4, -0.5, 4*8-6])
+color([0.5, 0.5, 1]) translate([-4, -0.5, tube_length*8-6])
 cube(size=[8, 1, 3], center=false);
 
-// } translate([0, -50, -1]) cube(size=[10, 100, 50]); }
+//} translate([0, -50, -1]) cube(size=[10, 500, 500]); }
 
-module ball_end() {
-  difference() {
-    ball_end_p();
-    ball_end_n();
-  }
-}
-
-module ball_end_p() {
-  union() {
-    translate([0, 0, 1.7+3.2+1-4]) difference() { sphere(r=4); translate([-5, -5, -6]) cube(size=[10,10,5]); }
-    cylinder(r=4, h=2);
-  }
-}
+//rotate([10, 0, 0]) axleround(h=8);
 
+// ball end shift 2.3mm down
 module ball_end_n() {
-  translate([0, 0, 1.7]) sphere(r=3.2);
+  translate([0, 0, 1.7]) sphere(r=3.05);
   translate([0, 0, -0.1]) cylinder(r=2.9, h=2);
 }
+
+module axleround(h = 24, axleradius = 2.3, axlemesh = 1.7) {
+  translate([0, 0, -h/2]) difference() {
+    cylinder($fn=16, r=axleradius, h=h);
+    translate([axlemesh/2, axlemesh/2, -1]) cube([axleradius, axleradius, h+2]);
+    translate([axlemesh/2, -axlemesh/2-axleradius, -1]) cube([axleradius, axleradius, h+2]);
+    translate([-axlemesh/2-axleradius, axlemesh/2, -1]) cube([axleradius, axleradius, h+2]);
+    translate([-axlemesh/2-axleradius, -axlemesh/2-axleradius, -1]) cube([axleradius, axleradius, h+2]);
+  }
+}