X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=reprap-play.git;a=blobdiff_plain;f=brompton-computer-guard.scad;h=efb3a8a129bd7bdfac21ca94a86c19401c152cc3;hp=b720bf1d879a30cc17e7e662d4afad57dad561de;hb=1f1a48c7ecc8938a779353150fa6a68b5da0c8ee;hpb=c88984757c32927d4cab9adaec78a7bec75825b5

diff --git a/brompton-computer-guard.scad b/brompton-computer-guard.scad
index b720bf1..efb3a8a 100644
--- a/brompton-computer-guard.scad
+++ b/brompton-computer-guard.scad
@@ -1,14 +1,17 @@
 // -*- C -*-
 
-arch_height = 24;
+arch_height = 18;
 arch_width = 75;
 end_width = 25;
 
-arch_thick = 5;
+arch_thick = 4;
 
 arch_breadth = 25;
 
-hole_dia = 3 + 0.5;
+hole_dia = 4 + 0.5;
+
+pbase_tab = 12;
+pbase_thick = 2;
 
 // computed
 
@@ -18,26 +21,37 @@ echo(arch_alpha,arch_beta);
 arch_in_rad = arch_width/2 / sin(arch_beta);
 arch_to_chord = arch_in_rad * cos(arch_beta);
 
+inner_pbase_thick = 6;
+echo(inner_pbase_thick);
+
+inner_pbase_rad = arch_in_rad * 2;
+
 end_thick = arch_thick;
 
 holes = [[[  5  , 5  ], [16  , 21]], // left
-	 [[ 18.5, 4.5], [ 4.5, 22]]]; // right
+	 [[ 18.5, 4.5], [ 4.5, 21]]]; // right
+
+module ArchCircle(rad){
+  translate([0,-arch_to_chord])
+    circle(rad, $fa=0.1);
+}
 
-module ArchProfile(){
+module ArchProfile(pbase){
   intersection(){
     translate([-200,0])
       square([400,200]);
-    union(){
-      translate([0,-arch_to_chord]){
-	difference(){
-	  circle(arch_in_rad + arch_thick, $fa=0.1);
-	  circle(arch_in_rad, $fa=0.1);
-	}
+    difference(){
+      union(){
+	ArchCircle(arch_in_rad + arch_thick);
+	for (m=[0,1])
+	  mirror([m,0])
+	    translate([arch_width/2,0])
+	    multmatrix([[1,pbase ? -0.75 : 0,0,0],
+			[0,1,0,0],
+			[0,0,1,0],
+			[0,0,0,1]])
+	    square([end_width, pbase ? pbase_tab : end_thick]);
       }
-      for (m=[0,1])
-	mirror([m,0])
-	  translate([arch_width/2,0])
-	  square([end_width, end_thick]);
     }
   }
 }
@@ -54,12 +68,38 @@ module Holes(){
   }
 }
 
+module MainCutout(){
+  ArchCircle(arch_in_rad);
+}
+
 module Arch(){
   difference(){
-    rotate([0,0,180])
-      linear_extrude(height=arch_breadth) ArchProfile();
+    rotate([0,0,180]){
+      linear_extrude(height=arch_breadth) {
+	difference(){
+	  ArchProfile(false);
+	  MainCutout();
+	}
+      }
+      difference(){
+	linear_extrude(height=pbase_thick){
+	  difference(){
+	    hull(){
+	      ArchProfile(true);
+	      ArchProfile(false);
+	    }
+	    intersection(){
+	      MainCutout();
+	      translate([0, -inner_pbase_thick
+			 - (inner_pbase_rad - arch_in_rad)])
+		ArchCircle(inner_pbase_rad);
+	    }
+	  }
+	}
+      }
+    }
     Holes();
   }
 }
 
-Arch();
+rotate([0,0,45]) Arch();