Add model for the tape fan [WIP]

tape_fan.scad

@@ -0,0 +1,50 @@
+$fn = 100;
+fs = 1;  // roughly the size of straight party of curves
+w1 = 1;   // cookie cutter, thicker side
+w2 = 1;   // cookie cutter, thinner side
+h = 1;     // cookie cutter height
+mh = 2;     // thickness of connection to window
+sw = 18;    // size of window
+dt = 2;     // dough thickness at the window carve, '0' for cut
+
+function fn(a, b) = round(sqrt(pow(a[0]-b[0],2) + (pow(a[1]-b[1], 2)))/fs);
+
+module shape() cylinder(h, w1/2, w2/2, $fn=12);
+
+function b_pts(pts, n, idx) =
+    len(pts)>2 ? 
+        b_pts([for(i=[0:len(pts)-2])pts[i]], n, idx) * n*idx 
+            + b_pts([for(i=[1:len(pts)-1])pts[i]], n, idx) * (1-n*idx)
+        : pts[0] * n*idx 
+            + pts[1] * (1-n*idx);
+
+module b_curve(pts)
+    let (idx=fn(pts[0], pts[len(pts)-1]), n = 1/idx){
+        for (i= [0:idx-1])
+        hull(){
+           translate(b_pts(pts, n, i)) shape();
+           translate(b_pts(pts, n, i+1)) shape();
+    };}
+
+module spike() {
+  polygon([[0, 0], [10, 0], [5, 50]]);
+
+}
+
+// spike();
+
+blade = 8;
+
+module fan() {
+    for (i = [0 : blade]){
+        rotate( i * 360/blade, [0, 0, 1])
+        b_curve([[0, 0], [20, 30], [10, 45], [0, 37]]);
+    }
+
+    cylinder(h, d = 35);
+}
+
+difference() {
+    fan();
+    cylinder(h, d = 5);
+};