poster-tube-lid: introduce middle_bot_z (nfc)

[reprap-play.git] / poster-tube-lid.scad

diff --git a/poster-tube-lid.scad b/poster-tube-lid.scad
index 33d008f481287cf08c33029577e8d47c1bace1d5..2e3d6d3d9c2f08b69a9ddf1cae02019c518c58d2 100644 (file)
--- a/poster-tube-lid.scad
+++ b/poster-tube-lid.scad
@@ -1,7 +1,8 @@
 // -*- C -*-
 
 main_dia = 71.2 + 0.50 - 2.26;
-top_thick = 4;
+top_minthick_middle = 4;
+top_minthick_by_oring = 2.5;
 
 main_cnr = 4.0;
 
@@ -13,7 +14,7 @@ rivet_tall = 5.51 + 0.49;
 over_rivet_wall = 0.5;
 side_rivet_gap = 1.5;
 
-bayo_interf = 0.75;
+bayo_interf = 1.25;
 bayo_behind = 3.5;
 bayo_interf_width = 2.0;
 bayo_interf_slope = 0.75;
@@ -21,7 +22,7 @@ bayo_interf_slope = 0.75;
 oring_thick = 5.0;
 oring_bore = 62.0;
 
-oring_upper_embed_angle = 45;
+oring_upper_embed_angle = 80;
 oring_compress = 0.1; // proportion
 
 side_taper = 1.0;
@@ -34,6 +35,7 @@ bayo_slice_size = 1;
 
 brace_hole_width = 1.0;
 brace_above_below = 1.2;
+brace_end_shorter = 0.3;
 
 jig_thick = 1.4;
 jig_hole_dia = 3.0;
@@ -50,16 +52,23 @@ bayo_inramp_z = bayo_entry;
 oring_mid_dia = oring_bore + oring_thick;
 oring_outer_dia = oring_mid_dia + oring_thick;
 
-oring_y_rad = oring_thick/2 * (1 - oring_compress);
-oring_x_rad = oring_thick/2 / (1 - oring_compress);
+oring_oblate = (1 - oring_compress);
+
+oring_y_rad = oring_thick/2 * oring_oblate;
+oring_x_rad = oring_thick/2 / oring_oblate;
 
 seal_thick = oring_y_rad * (1 + cos(oring_upper_embed_angle));
 
 side_height = rivet_posn + bayo_behind + rivet_thick/2;
 side_thick = rivet_tall + over_rivet_wall;
 
+top_thick = max(top_minthick_middle,
+               top_minthick_by_oring + oring_y_rad);
+
 top_z = top_thick + seal_thick;
 
+middle_bot_z = top_z - top_minthick_middle;
+
 bayo_entry = bayo_behind / 3.0;
 bayo_top_z = bayo_behind + rivet_thick + bayo_above_gap;
 bayo_entry_ramp = bayo_entry + bayo_interf;
@@ -81,7 +90,8 @@ bayo_l = bayo_m + bayo_interf * [ 1/bayo_interf_slope,  1 ];
 bayo_k = bayo_l + [ bayo_interf_width, 0 ];
 bayo_j = bayo_k + bayo_interf * [ 1/bayo_interf_slope, -1 ];
 bayo_i = bayo_j + [ rivet_width, 0 ];
-bayo_h = [ bayo_i[0], bayo_behind + rivet_thick + bayo_above_gap ];
+bayo_h = [ bayo_i[0], bayo_behind + rivet_thick
+                     + bayo_above_gap + bayo_interf ];
 bayo_g = [ bayo_m[0] - rivet_width, bayo_h[1] ];
 
 bayo_e = [-bayo_p[0], bayo_p[1]] - [rivet_entry_width,0];
@@ -122,7 +132,7 @@ module MainProfile(){
          square([10,10]);
        }
       }
-      polygon([[ -11,                   seal_thick        ],
+      polygon([[ -11,                   middle_bot_z      ],
               [ -11,                   top_z             ],
               [ main_cnr_pos[0],       top_z             ],
               [ side_thick,            main_cnr_pos[1]   ],
@@ -130,9 +140,18 @@ module MainProfile(){
               [ side_taper,            -side_height      ],
               [ 0,                     -rivet_posn       ],
               [ 0,                     seal_thick        ],
+              [ -oring_x_rad,          seal_thick        ],
               ],
              convexity=10);
     }
+    translate([ oring_mid_dia/2 - main_dia/2, 0 ])
+      hull(){
+      translate([ 0, oring_y_rad ])
+       scale([ 1/oring_oblate, oring_oblate ])
+       circle(oring_thick/2);
+      translate([ 0, oring_y_rad*2 - oring_thick/2 ])
+       circle(oring_thick/2);
+    }
   }
 }
 
@@ -173,8 +192,8 @@ module BayonetCutout(){
 }
 
 module ProfilesDemo(){ ////toplevel
-  translate([-20,0]) MainProfile();
-  polygon(bayo_polygon, convexity=10);
+  translate([-10,0]) MainProfile();
+  translate([+10,0]) polygon(bayo_polygon, convexity=10);
 }
 
 module Cover(){ ////toplevel
@@ -183,8 +202,8 @@ module Cover(){ ////toplevel
       rotate_extrude(convexity=10)
        translate([main_dia/2, 0])
        MainProfile();
-      translate([0,0, seal_thick])
-       cylinder(h= top_thick, r = main_dia/2 - 10);
+      translate([0,0, middle_bot_z])
+       cylinder(h= top_minthick_middle, r = main_dia/2 - 10);
     }
     for (r=[0,180])
       rotate([0,0, r])
@@ -194,7 +213,8 @@ module Cover(){ ////toplevel
       rotate([0,0, r]) {
        height = top_thick - brace_above_below*2;
        translate([0,0, seal_thick + brace_above_below + height/2 ])
-       cube(center=true, [ main_dia, brace_hole_width, height ]);
+       cube(center=true, [ oring_bore - brace_end_shorter,
+                           brace_hole_width, height ]);
       }
     }
   }