mudguard-bracket: wip

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/mudguard-bracket.scad b/mudguard-bracket.scad
index 52f654cb72918ced7ac059e62acf4ef2a1834655..bded91ba9939c08836db0f0b70608b9a6799e21d 100644 (file)
--- a/mudguard-bracket.scad
+++ b/mudguard-bracket.scad
@@ -10,11 +10,29 @@ wings_inner_th = 1;
 wings_main_th = 2.5;
 wings_cup_z = -34;
 
+tubeswidth_top = 23.5;
+tubeswidth_bot = 29;
+tubeswidth_dz = 26;
+tube_dia = 18;
+screw_hole_z = 13;
+
+beamacross_h = 15;
+
 $fs = 0.1;
 $fa = 3;
 
 // calculated
 
+function tubeswidth_at_z(z) =
+  tubeswidth_bot +
+  (tubeswidth_top - tubeswidth_bot) * (z / tubeswidth_dz);
+
+bracket_bot_z = screw_hole_z - beamacross_h/2;
+bracket_top_z = screw_hole_z + beamacross_h/2;
+bracket_bot_xsz = tubeswidth_at_z(bracket_bot_z) + tube_dia * 1.5;
+bracket_top_xsz = tubeswidth_at_z(bracket_top_z) + tube_dia * 1.5;
+
+wing_top_ea_x = -bracket_top_xsz/2 + wings_main_th/2;
 
 module AtWingCupElevation () {
   translate([ -wings_dist_x, wings_cup_z ])
@@ -54,17 +72,32 @@ module WingCupElevationPositive () {
 }
 
 module WingElevation(){
-  AtWingCupElevation(){
-    translate([ -(wings_inner_th + wings_main_th)/2,
-               wings_cup_inner/2 ])
-      circle(r = wings_main_th);
+  hull(){
+    AtWingCupElevation(){
+      translate([ -(wings_inner_th + wings_main_th)/2,
+                 wings_cup_inner/2 ])
+       circle(r = wings_main_th);
+    }
+    // TODO add the other end here
+  }
+}
+
+module BracketAcrossElevation(){
+  hull(){
+    translate([ 0, bracket_bot_z ])
+      rectfromto([ -bracket_bot_xsz/2, 0 ],
+                [ +bracket_bot_xsz/2, 1 ]);
+    translate([ 0, bracket_top_z ])
+      rectfromto([ -bracket_top_xsz/2, -1 ],
+                [ +bracket_top_xsz/2, 0 ]);
   }
 }
 
-module WingCupElevationDemo(){
+module ElevationDemo(){
   translate([0,0,2]) color("red") WingCupElevationNegative();
   translate([0,0,1]) color("blue") WingElevation();
   WingCupElevationPositive();
+  BracketAcrossElevation();
 }
 
 /*WingsElevation () {
@@ -75,4 +108,4 @@ module WingCupElevationDemo(){
 
 */
 
-WingCupElevationDemo();
+ElevationDemo();