diff --git a/base.scad b/base.scad
index 03add45..36ccb92 100644
--- a/base.scad
+++ b/base.scad
@@ -1,38 +1,46 @@
 include <dims.scad>
 
-sleeve_h = 150;
-channel_h = cap_depth;
-base_wall = 10;
-standoff_height = 50;
+bid = 149;
+bod = 7.75 * 25.4;
+bh = 200;
+taper = 20;
+top_thick = 25.4 * 2;
+armw = 50;
+armh = 15;
+armnotch = 5;
+arms = 3;
 otod_pad = 1.8;
-neg_h = sleeve_h + 10;
-base_r = 200;
-base_thick = 30;
-tongue_w = otod + 50;
 
-module negative() {
+module shell() {
     difference() {
-        translate([-250 - eps, -250 - eps, -10])
-            cube([500 + 2 * eps, 500 + 2 * eps, neg_h + 10]);
-        cylinder(h=neg_h + eps, r=base_r);
-    }
-    difference() {
-        cylinder(h=neg_h, r=(otod + otod_pad) / 2);
-        for (i = [0 : 1]) {
-            rotate([0, 0, 90 + 180 * i]) {
-                translate([-(otod + otod_pad) / 2, -base_wall/2, -eps]) union() {
-                    cube([base_wall, base_wall, standoff_height]);
-                }
-            }
-        }
-    }
-    difference() {
-        cylinder(h=sleeve_h - base_thick, r=base_r - base_thick);
-        translate([-tongue_w / 2, -otod, -eps]) cube([tongue_w, base_r + otod, base_thick]);
+        cylinder(h=bh, r1=bod/2, r2=bod/2-taper);
+        translate([0, 0, -2*eps]) cylinder(h=bh - top_thick, r=bid/2);
     }
 }
 
 difference() {
-    translate([-250, -250, eps]) cube([500, 500, sleeve_h]);
-    negative();
-}
\ No newline at end of file
+    union() {
+        intersection() {
+            for (i = [0 : arms-1]) {
+                rotate([0, 0, i * 360/arms]) {
+                    difference() {
+                        translate([-armw/2, 0, -armh + armnotch]) cube([armw, bod/2, armh]);
+                        for (i = [2 : 5])
+                            translate([i % 2 == 0 ? 6 : -6, (i+4.5) * (bid/22), -armh])
+                                cylinder(h=2*armh, r=3.5);
+                    }
+                }
+            }
+            translate([0, 0, -2 * armh + armnotch]) cylinder(h=armh * 2, r=bod/2-1);
+        }
+        translate([0, 0, -armh + armnotch]) {
+            difference() {
+                cylinder(h=armh*2, r=otod/2+wall_thickness + otod_pad);
+                translate([0, 0, armh + 2*eps]) cylinder(h=armh + 2*eps, r=(otod + otod_pad)/2);
+                translate([-channel_w/2, 0, armh+2*eps]) cube([channel_w, otod+eps, armh]);
+            }
+        }
+    }
+    shell();
+}
+