docs: add readme, images

README.md

@@ -0,0 +1,53 @@
+# Lock Puzzle
+
+A 3D-printed puzzle box written in OpenSCAD.
+
+![The puzzle box in its closed state](images/lockpuzzle_rendered_locked.png)
+
+![The puzzle box in its opened state](images/lockpuzzle_rendered_unlocked.png)
+
+## Usage
+
+### Rendering
+
+1. Make sure you have OpenSCAD installed.
+2. In the file `render.sh`, change at least the `LENGTH` variable to the length of your chosen password.
+    - You can also change other settings such as the alphabet, or the diameter of the box.
+	- The default diameter (and the one the printed model has been tested with) is 50mm.  The lock mechanism takes 20mm off this, so the inner diameter is 30mm.
+	- The length of the box currently depends on the length of the password, and is `(LENGTH*10+15)mm`.  The length of the inner space is `(LENGTH*10)mm`.
+3. Run `./render.sh`, which will create all the STL files you'll need in the `out/` directory.
+    - If you are using an OpenSCAD version without support for the Manifold rendering engine, remove the `--backend=manifold` argument.
+
+### 3D Printing
+
+Print the following objects:
+
+- 1 x `case.stl`
+- 1 x `plug.stl`
+- 1 x `key_dial_${character}.stl` for every character in your password.
+- LENGTH x `ring_click.stl`
+- 1 x `ring.stl`
+
+### Assembly
+
+1. Start with the printed case:
+
+    ![Rendering of the main case of the lock](images/lockpuzzle_assembly_01.png)
+2. Add the first ring to the case as shown here.  Note that the outward-pointing position indicator and the sideways-pointing "clicker" must be oriented exactly as shown here:
+
+    ![The first ring placed on the case](images/lockpuzzle_assembly_02.png)
+3. Add the first dial case as shown here.
+
+    ![The first dial placed on the case](images/lockpuzzle_assembly_03.png)
+4. Repeat steps 2 and 3 until you reach the last dial.
+
+    ![The remaining rings and dials placed on the case](images/lockpuzzle_assembly_04.png)
+5. Add the final ring to the case as shown here.  Note the absence of the clicker.
+
+    ![The final ring placed on the case](images/lockpuzzle_assembly_05.png)
+6. Turn all dials so that the cutout lines up with the long slot in the case.  Turning the dials might require quite some force at first, but after a few turns the clicker will wear down a bit, which will make the dials easier to turn.
+
+    ![All dials lined up with the slot in the case](images/lockpuzzle_assembly_06.png)
+7. Finally, insert the plug all the way, then turn the dials to lock the puzzle box:
+
+    ![The plug inserted into the case, closing the puzzle box](images/lockpuzzle_assembly_07.png)

case.scad

@@ -15,10 +15,13 @@ module case(n=5, diameter=50, tolerance=0.2, $fn=60) {
           }
           // cutouts for e-clips
           rotate([0,0,45]) {
-            for (i = [0:n]) {
-              translate([0,0,10*i+3]) {
-                cube([5, diameter, 3], center=true);
-                cube([diameter, 5, 3], center=true);
+            for (j = [0:2]) {
+              rotate([0,0,120*j]) {
+                for (i = [0:n]) {  
+                  translate([0,diameter/4,10*i+3]) {
+                    cube([5, diameter/2, 3], center=true);
+                  }
+                }
               }
             }
           }
@@ -36,6 +39,7 @@ module case(n=5, diameter=50, tolerance=0.2, $fn=60) {
 //  DEFAULTS FOR COMMAND LINE INVOCATION
 
 ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+
 N = 5;
 DIAMETER = 50;
 TOLERANCE = 0.2;

e_ring.scad

@@ -1,80 +0,0 @@
-
-
-module e_ring(alphabet_length=26, dia=48, width=3, thick=2, spoke_depth=4.5, spoke_width=7, key_depth=3, key_length=4, tolerance = 0.2, indicator=false, clicker=false, $fn=60) {
-  
-  difference() {  // halfing
-    union() {
-      // outer ring
-      difference() {
-        cylinder(d=dia, h=width-4*tolerance, center=true);
-        cylinder(d=dia-2*thick, h=width+1, center=true);
-      }
-      // key spokes
-      difference() {
-        union() {
-          intersection() {
-            cube([spoke_width, dia, width], center=true);
-            cylinder(d=dia, h=width-4*tolerance, center=true);
-          }
-          intersection() {
-            cube([dia, spoke_width, width], center=true);
-            cylinder(d=dia, h=width-4*tolerance, center=true);
-          }
-        }
-        cylinder(d=dia-2*spoke_depth+2*tolerance, h=width+1, center=true);
-      }
-      // keys
-      difference() {
-        union() {
-          cube([key_length, dia-spoke_depth, width-4*tolerance], center=true);
-          cube([dia-spoke_depth, key_length, width-4*tolerance], center=true);
-        }
-        cube([dia-spoke_depth*2-key_depth*2, dia-spoke_depth*2-key_depth*2, width+1], center=true);
-      }
-      // indicator
-      if (indicator) {
-        rotate([0,0,45]) {
-          translate([-dia/2,0,0]) {
-            cube([1.5, width/2, width-4*tolerance], center=true);
-          }
-        }
-      }
-      // clicker
-      if (clicker) {
-        rotate([0,0,45+(floor(alphabet_length/4))*360/alphabet_length]) {
-          translate([-dia/2+3,0,0]) {
-            cube([3, 4, width-4*tolerance], center=true);
-          }
-          translate([-dia/2+3.5,0,width/2-0.5]) {
-            scale([0.5,1,1]) {
-              rotate([0,0,45]) {
-                cylinder($fn=4, h=1, d1=5.6, d2=3);
-              }
-            }
-          }
-        }
-      }
-    }
-    translate([-dia/2-2, -tolerance, -width]) {
-      cube([dia+4, dia, 2*width]);
-    }
-  }
-}
-
-
-//  DEFAULTS FOR COMMAND LINE INVOCATION
-
-ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
-DIAMETER = 50;
-TOLERANCE = 0.2;
-FN = 60;
-INDICATOR = false;
-CLICKER = false;
-
-
-e_ring(
-  alphabet_length=len(ALPHABET),
-  dia=DIAMETER-2,
-  indicator=INDICATOR,
-  clicker=CLICKER,
-  tolerance=TOLERANCE, $fn=FN);

key_dial.scad

@@ -1,26 +1,27 @@
 
-module key_dial(alphabet="ABCDEFGHIJKLMNOPQRSTUVWXYZ", key="A", width=7, dia=50, thick=5.5, key_width=4, key_height=3, text_depth=1, text_width=4, antipick=1.5, tolerance = 0.2, $fn = 60) {
+module key_dial(alphabet="ABCDEFGHIJKLMNOPQRSTUVWXYZ", key="C", width=7, dia=50, thick=5.5, key_width=4, key_height=3, text_depth=1, font_size=-1, antipick=1.5, tolerance = 0.2, $fn = 60) {
   key_indices = search(key, alphabet, 0);
   assert(len(key_indices[0]) == 1, "key character not unique");
   key_index = key_indices[0][0];
+  _font_size = font_size > 0 ? font_size : min(dia*PI/len(alphabet)/1.6, dia/10);
   rotate([-0.5/len(alphabet)*360,0,0]) {
     difference() {
       rotate([0,90,0]) {
-        cylinder($fn=len(alphabet), h=width, d=dia, center=true);
+        cylinder($fn=$fn, h=width, d=dia, center=true);
       }
       // inner ring
       rotate([0,90,0]) {
-        cylinder($fn=60, h=width+2, d=dia-thick*2, center=true);
+        cylinder($fn=$fn, h=width+2, d=dia-thick*2, center=true);
       }
       // key
-      rotate([((0.5)/len(alphabet)) * 360,0,0]) {
+      rotate([45+((0.5+key_index)/len(alphabet)) * 360,0,0]) {
         translate([0,0,dia/2-thick]) {
           cube([width+2, key_width, key_height*2], center=true);
         }
       }
       // anti-picking keys
-      for (i = [1:len(alphabet)-1]) {
-        rotate([((i+0.5)/len(alphabet)) * 360,0,0]) {
+      for (i = [1:len(alphabet)]) {
+        rotate([45+((i+0.5)/len(alphabet)) * 360,0,0]) {
           translate([width/2,0,dia/2-thick]) {
             cube([2*antipick, key_width, key_height*2], center=true);
           }
@@ -29,9 +30,12 @@ module key_dial(alphabet="ABCDEFGHIJKLMNOPQRSTUVWXYZ", key="A", width=7, dia=50,
       // text
       for (i = [0:len(alphabet)]) {
         rotate([((i+0.5)/len(alphabet)) * 360,0,0]) {
-          translate([0,0,dia/2-text_depth]) {
+          translate([-width/2-1,-dia/2,dia/2-0.3]) {
+            cube([width+2,dia,5]);
+          }
+          translate([0,0,dia/2-text_depth-0.3]) {
             linear_extrude(height=text_depth+1, convexity=3) {
-              text(alphabet[(i+key_index)%len(alphabet)], size=text_width, halign="center", valign="center");
+              text(alphabet[i], size=_font_size, halign="center", valign="center");
             }
           }
         }
@@ -44,10 +48,10 @@ module key_dial(alphabet="ABCDEFGHIJKLMNOPQRSTUVWXYZ", key="A", width=7, dia=50,
 //  DEFAULTS FOR COMMAND LINE INVOCATION
 
 ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
-KEY = "A";
+KEY = "C";
 DIAMETER = 50;
 TOLERANCE = 0.2;
-FN = 60;
+FN = 120;
 INDEX = 0;
 
 rotate([0,-90,0]) {

lockpuzzle.scad

@@ -1,38 +1,38 @@
 
 use <key_dial.scad>;
-use <e_ring.scad>;
+use <ring.scad>;
 use <case.scad>;
 use <plug.scad>;
 
 
-module lock(alphabet="ABCDEFGHIJKLMNOPQRSTUVWXYZ", password="CHAOS", text_width=4, diameter=50, tolerance=0.2, $fn= 60) {
+module lock(alphabet="ABCDEFGHIJKLMNOPQRSTUVWXYZ", password="CHAOS", diameter=50, tolerance=0.2, $fn=60) {
 
   n = len(password);
+  key_indices=search(password, alphabet);
 
   for (i = [0:n-1]) {
-    translate([i*10,0,0]) key_dial(alphabet, key=password[i], dia=diameter, text_width=text_width);
+    rotate([-key_indices[i]/len(alphabet)*360,0,0]) {
+      translate([i*10,0,0]) {
+        key_dial(alphabet, key=password[i], dia=diameter);
+      }
+    }
   }
 
   for (i = [0:n]) {
     translate([-5+10*i,0,0]) {
       rotate([0,0,180]) {
-        rotate([-45,0,0]) {
-          rotate([0,90,0]) {
-            e_ring(dia=diameter-2, indicator=true, clicker=i>0);
-          }
-        }
-        rotate([135,0,0]) {
-          rotate([0,90,0]) {
-            e_ring(dia=diameter-2);
-          }
+        rotate([0,90,0]) {
+          ring(dia=diameter-2, clicker=i>0);
         }
       }
     }
   }
 
-  case(n, diameter=diameter);
-
-  plug(n, diameter=diameter);
+  
+  rotate([45,0,0]) {
+    case(n, diameter=diameter);
+    plug(n, diameter=diameter);
+  }
 
 }
 

render.sh

@@ -1,20 +1,19 @@
 #!/bin/bash
 
 ALPHABET=ABCDEFGHIJKLMNOPQRSTUVWXYZ
-N=5
+LENGTH=5
 DIAMETER=50
 TOLERANCE=0.2
 FN=60
 
-ARGS=("-q" "-DALPHABET=\"$ALPHABET\"" "-DN=$N" "-DDIAMETER=$DIAMETER" "-DTOLERANCE=$TOLERANCE" "-DFN=$FN")
+ARGS=("--backend=manifold" "-q" "-DALPHABET=\"$ALPHABET\"" "-DN=$LENGTH" "-DDIAMETER=$DIAMETER" "-DTOLERANCE=$TOLERANCE" "-DFN=$FN")
 
 mkdir -p out
 
 openscad "${ARGS[@]}" -o out/plug.stl plug.scad
 openscad "${ARGS[@]}" -o out/case.stl case.scad
-openscad "${ARGS[@]}" -o out/e_ring.stl e_ring.scad
-openscad "${ARGS[@]}" -DINDICATOR=true -o out/e_ring_indicator.stl e_ring.scad
-openscad "${ARGS[@]}" -DINDICATOR=true -DCLICK=true -o out/e_ring_indicator_click.stl e_ring.scad
+openscad "${ARGS[@]}" -o out/ring.stl ring.scad
+openscad "${ARGS[@]}" -DCLICKER=true -o out/ring_click.stl ring.scad
 
 while read -rn1 char; do
     openscad "${ARGS[@]}" "-DKEY=\"$char\"" -o "out/key_dial_${char}.stl" key_dial.scad

ring.scad

@@ -0,0 +1,85 @@
+
+
+module ring(alphabet_length=26, dia=48, width=3, thick=2, spoke_depth=4.5, spoke_width=7, key_depth=3, key_length=4, tolerance = 0.2, indicator=false, clicker=false, $fn=60) {
+  
+  difference() {  // halfing
+    union() {
+      // outer ring
+      difference() {
+        cylinder(d=dia, h=width-4*tolerance, center=true);
+        cylinder(d=dia-2*thick, h=width+1, center=true);
+      }
+      // key spokes
+      difference() {
+        union() {
+          for (i = [0:2]) {
+            rotate([0,0,120*i]) {
+              intersection() {
+                translate([-dia/4,0,0]) {
+                  cube([dia/2, spoke_width, width], center=true);
+                }
+                cylinder(d=dia, h=width-4*tolerance, center=true);
+              }
+            }
+          }
+        }
+        cylinder(d=dia-2*spoke_depth+2*tolerance, h=width+1, center=true);
+      }
+      // keys
+      for (i = [0:2]) {
+        rotate([0,0,120*i]) {
+          translate([-dia/2+spoke_depth+key_depth/2-1,0,0]) {
+            cube([key_depth+2, key_length, width-4*tolerance], center=true);
+          }
+        }
+      }
+      // indicator
+        translate([-dia/2,0,0]) {
+          cube([1.5, width, width-4*tolerance], center=true);
+        }
+      // clicker
+      if (clicker) {
+        rotate([0,0,floor(alphabet_length/3)*360/alphabet_length-45]) {
+          translate([-dia/2+3,0,0]) {
+            cube([3, 4, width-4*tolerance], center=true);
+          }
+          translate([-dia/2+3.5,0,width/2-0.5]) {
+            scale([0.5,1,1]) {
+              rotate([0,0,45]) {
+                cylinder($fn=4, h=1, d1=5.6, d2=3);
+              }
+            }
+          }
+        }
+      }
+    }
+    // Ring cut
+    translate([-dia/2+thick-0.5, -0.25, -width/2]) {
+      cube([spoke_depth+key_depth,0.5, width]);
+    }
+    translate([-dia/2, width/2, -width/2]) {
+      cube([thick,0.5, width]);
+    }
+    translate([-dia/2+thick-0.5, 0, -width/2]) {
+      cube([0.5, width/2, width]);
+    }
+  }
+}
+
+
+//  DEFAULTS FOR COMMAND LINE INVOCATION
+
+ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+DIAMETER = 50;
+TOLERANCE = 0.2;
+FN = 60;
+INDICATOR = false;
+CLICKER = false;
+
+
+ring(
+  alphabet_length=len(ALPHABET),
+  dia=DIAMETER-2,
+  indicator=INDICATOR,
+  clicker=CLICKER,
+  tolerance=TOLERANCE, $fn=FN);