X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=reprap-play.git;a=blobdiff_plain;f=cliphook.scad;h=22f08f54ec09a1d7d441488b755ded87f6cb753d;hp=87787d82fb31bf665273e251bdb33e2f40a3e091;hb=1cf13680665629e8fa0acba6e078e2a6157533a3;hpb=affb37ea132276b85f1617dc0f36cc04538fd9cf

diff --git a/cliphook.scad b/cliphook.scad
index 87787d8..22f08f5 100644
--- a/cliphook.scad
+++ b/cliphook.scad
@@ -1,3 +1,22 @@
+// -*- C -*-
+//
+// cliphook.scad
+//
+// 3D design for a small clippy hook
+// Copyright 2012,2016 Ian Jackson
+//
+// This work is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This work is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this work.  If not, see <http://www.gnu.org/licenses/>.
 
 function ClipHook_r2(w,g,l,ye,k) = w/2 + g + w/2;
 function ClipHook_r3(w,g,l,ye,k) = k * (ClipHook_r2(w,g,l,ye,k) + w + g);
@@ -5,7 +24,30 @@ function ClipHook_yd(w,g,l,ye,k) = g/2 + w + g + w/2 - ClipHook_r3(w,g,l,ye,k);
 function ClipHook_xe(w,g,l,ye,k) =
         l*1.5 + w +
 	sqrt(pow( ClipHook_r3(w,g,l,ye,k),      2) -
-	     pow( ClipHook_yd(w,g,l,ye,k) + ye, 2));
+	     pow( ClipHook_yd(w,g,l,ye,k) - ye, 2));
+
+module FlatArc(cx,cy,r1,r2,a1,a2=361,$fn=$fn) {
+  astep = (a2-a1)/6;
+  size = 5*(r2/2);
+  translate([cx,cy,0]) {
+    intersection() {
+      difference() {
+	circle(r=r2);
+	translate([0,0,-1])
+	  circle(r=r1);
+      }
+      scale(size) {
+	for (ai=[0:4]) {
+	  //echo(" jarc ", a1,a2, astep, ai, a1 + astep*ai );
+	  rotate(a1 + astep*ai) {
+	    polygon([ [0,0], [1,0],
+		      [cos(astep*2),sin(astep*2)] ]);
+	  }
+	}
+      }
+    }
+  }
+}
 
 module ClipHook_2D(w,g,l,ye,k,h) {
   r2 =  ClipHook_r2(w,g,l,ye,k);
@@ -15,7 +57,7 @@ module ClipHook_2D(w,g,l,ye,k,h) {
 
   xd = l*1.5 + w;
   xc = -l/2;
-  yc = g/w + w/2;
+  yc = g/2 + w/2;
 
   alpha = atan2((xe-xd)/r3, (ye-yd)/r3);
 
@@ -26,29 +68,7 @@ module ClipHook_2D(w,g,l,ye,k,h) {
 
   module jcirc(x,y) { translate([x,y,0]) circle(r=w/2); }
   module jbox(y,x1,x2) { translate([x1,y-w/2,0]) square(size=[x2-x1, w]); }
-  module jarc(cx,cy,r,a1=0,a2=360) {
-    astep = (a2-a1)/6;
-    size = 5*(r+w/2);
-    translate([cx,cy,0]) {
-      intersection() {
-	difference() {
-		circle(r=r+w/2);
-		translate([0,0,-1])
-			circle(r=r-w/2, h=h+2);
-	}
-	scale(size) {
-	  for (ai=[0:4]) {
-	    echo(" jarc ", a1,a2, astep, ai, a1 + astep*ai );
-	    rotate(a1 + astep*ai) {
-	      polygon([ [0,0], [1,0],
-			[cos(astep*2),sin(astep*2)] ]);
-	    }
-	  }
-	}
-      }
-    }
-  }
-
+  module jarc(cx,cy,r,a1=0,a2=360) { FlatArc(cx,cy,r-w/2,r+w/2,a1,a2); }
 
   jcirc(-xc, -yc);
   jbox(-yc, xc, -xc);
@@ -58,12 +78,26 @@ module ClipHook_2D(w,g,l,ye,k,h) {
   jcirc(xe,ye);
 }
 
-module ClipHook(w=1.2, g=0.2, l=0.0, ye=0, k=2.0, h=3.5, demo=false) {
-  linear_extrude(height=h)
-    ClipHook_2D(w,g,l,ye,k);
-  if (demo)
-    %linear_extrude(height=h)
-      translate([l+w,0,0]) rotate(180) ClipHook_2D(w,g,l,ye,k);
+module ClipHook(w=1.2, g=0.2, l=0.0, ye=0, k=2.0, h=3.5, demo=false,
+		cupcaph=0, cupgapg=0) {
+  difference() {
+    linear_extrude(height=h)
+      ClipHook_2D(w,g,l,ye,k);
+    if (cupcapg != 0) {
+      translate([-g+0.01,-(w+g),h-cupcapg])
+      cube([w,(w+g),cupcaph+1]);
+    }
+  }
+  if (cupcaph != 0) {
+    translate([-l/2, g/2+w/2, h-0.01])
+      intersection() {
+        cylinder(r=ClipHook_r2(w,g,l,ye,k)+w*0.4, h=cupcaph, $fn=16);
+	translate([-50-g,-50,-1]) cube([50,100,h+2]);
+      }
+  }
 }
 
-ClipHook(l=3, ye=1.5, k=1, demo=true);
+if (ClipHook_demo) {
+  ClipHook(l=0, k=1, cupcaph=1, cupcapg=0.4);
+  %translate([l+w,0,0]) rotate(180) ClipHook(l=0, k=1, cupcaph=1, cupcapg=0.4);
+}