// -*- C -*-
-cover_zsz = 45;
-cover_len = 70;
+arch_height = 18;
+arch_width = 75;
+end_width = 25;
-attach_tube_dia = 18;
+arch_thick = 4;
-attach_cx = -15;
-attach_cdz = -10;
-attach_w = 25;
+arch_breadth = 25;
-attach_inrad = 25; ///
-attach_hole_dist = 5; ///
-attach_hole_dia = 4 + 0.5; ///
-attach_ang = 45;
+hole_dia = 4 + 0.5;
-// calculated
+pbase_tab = 12;
+pbase_thick = 2;
-cover_lcircle_r = cover_zsz / (1 + 1/sqrt(2));
+// computed
-base_len = cover_len - cover_lcircle_r;
+arch_alpha = atan(arch_height / (arch_width/2));
+arch_beta = 2*arch_alpha;
+echo(arch_alpha,arch_beta);
+arch_in_rad = arch_width/2 / sin(arch_beta);
+arch_to_chord = arch_in_rad * cos(arch_beta);
-attach_total_len =
- attach_inrad + attach_tube_dia + attach_hole_dist + attach_hole_dia/2;
+inner_pbase_thick = 6;
+echo(inner_pbase_thick);
-module RearSideTemplate(){
- polygon([[0.1,0],
- [-base_len,0],
- [-base_len,-cover_zsz],
- [0.1, -cover_zsz]]);
- translate([-base_len, -cover_zsz + cover_lcircle_r])
- circle(r=cover_lcircle_r);
+inner_pbase_rad = arch_in_rad * 2;
+
+end_thick = arch_thick;
+
+holes = [[[ 5 , 5 ], [16 , 21]], // left
+ [[ 18.5, 4.5], [ 4.5, 21]]]; // right
+
+module ArchCircle(rad){
+ translate([0,-arch_to_chord])
+ circle(rad, $fa=0.1);
}
-module AttachTemplate(){
- hull(){
-// polygon([[0, 0],
-// [-0.1, 0],
-// [-0.1, -cover_zsz],
-// [0, -cover_zsz]]);
- translate([attach_cx, -attach_cdz]) rotate([0,0,-attach_ang]) {
- polygon([[-attach_cx, attach_w/2],
- [0, -attach_w/2],
- [attach_total_len, -attach_w/2],
- [attach_total_len, attach_w/2]]);
- translate([attach_total_len, 0])
- circle(r=attach_w/2);
+module ArchProfile(pbase){
+ intersection(){
+ translate([-200,0])
+ square([400,200]);
+ 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]);
+ }
}
}
}
-//module Tube(){
-// translate(
+module Holes(){
+ for (m=[0,1]) {
+ mirror([1-m,0])
+ translate([arch_width/2, 50, 0])
+ rotate([90,0,0])
+ for (h=holes[m]) {
+ translate(h)
+ cylinder(r=hole_dia/2, h=100, $fn=20);
+ }
+ }
+}
+
+module MainCutout(){
+ ArchCircle(arch_in_rad);
+}
+
+module Arch(){
+ difference(){
+ 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();
+ }
+}
-color("blue") RearSideTemplate();
-AttachTemplate();
+rotate([0,0,45]) Arch();