diff --git a/upper_case.png b/upper_case.png
index 8b16bff..8b4afc9 100644
Binary files a/upper_case.png and b/upper_case.png differ
diff --git a/upper_case.scad b/upper_case.scad
index 30d64fa..35b807c 100644
--- a/upper_case.scad
+++ b/upper_case.scad
@@ -6,19 +6,27 @@ $fn = 64;
 
 color("SaddleBrown") difference() {
   // case
-  hull() {
-    translate([-case_thickness, -case_thickness, 0]) cylinder(h=upper_case_height, r=pcb_radius+1);
-    translate([pcb_width-2*pcb_radius+case_thickness, -case_thickness, 0]) cylinder(h=upper_case_height, r=pcb_radius+1);
-    translate([-case_thickness, pcb_depth-2*pcb_radius+case_thickness, 0]) cylinder(h=upper_case_height, r=pcb_radius+1);
-    translate([pcb_width-2*pcb_radius+case_thickness, pcb_depth-2*pcb_radius+case_thickness, 0]) cylinder(h=upper_case_height, r=pcb_radius+1);
+  union() {
+    hull() {
+      translate([-case_thickness, -case_thickness, 0]) cylinder(h=upper_case_height/2, r=pcb_radius+1);
+      translate([pcb_width-2*pcb_radius+case_thickness, -case_thickness, 0]) cylinder(h=upper_case_height/2, r=pcb_radius+1);
+      translate([-case_thickness, pcb_depth-2*pcb_radius+case_thickness, 0]) cylinder(h=upper_case_height/2, r=pcb_radius+1);
+      translate([pcb_width-2*pcb_radius+case_thickness, pcb_depth-2*pcb_radius+case_thickness, 0]) cylinder(h=upper_case_height/2, r=pcb_radius+1);
+    }
+    translate([0,0,upper_case_height/2]) hull() {
+      translate([-case_thickness, -case_thickness, 0]) resize(newsize=[2*(pcb_radius+1),2*(pcb_radius+1),upper_case_height]) sphere(r=pcb_radius+1);
+      translate([pcb_width-2*pcb_radius+case_thickness, -case_thickness, 0]) resize(newsize=[2*(pcb_radius+1),2*(pcb_radius+1),upper_case_height]) sphere(r=pcb_radius+1);
+      translate([-case_thickness, pcb_depth-2*pcb_radius+case_thickness, 0]) resize(newsize=[2*(pcb_radius+1),2*(pcb_radius+1),upper_case_height]) sphere(r=pcb_radius+1);
+      translate([pcb_width-2*pcb_radius+case_thickness, pcb_depth-2*pcb_radius+case_thickness, 0]) resize(newsize=[2*(pcb_radius+1),2*(pcb_radius+1),upper_case_height]) sphere(r=pcb_radius+1);
+    }
   }
 
   // pcb
   hull() {
-    cylinder(h=upper_case_height+0.1, r=pcb_radius+1);
-    translate([pcb_width-2*pcb_radius, 0, 0]) cylinder(h=upper_case_height+0.1, r=pcb_radius+1);
-    translate([0, pcb_depth-2*pcb_radius, 0]) cylinder(h=upper_case_height+0.1, r=pcb_radius+1);
-    translate([pcb_width-2*pcb_radius, pcb_depth-2*pcb_radius, 0]) cylinder(h=upper_case_height+0.1, r=pcb_radius+1);
+    translate([3,3,0]) cylinder(h=upper_case_height+0.1, r=pcb_radius+1);
+    translate([pcb_width-2*pcb_radius-3, 3, 0]) cylinder(h=upper_case_height+0.1, r=pcb_radius+1);
+    translate([3, pcb_depth-2*pcb_radius-3, 0]) cylinder(h=upper_case_height+0.1, r=pcb_radius+1);
+    translate([pcb_width-2*pcb_radius-3, pcb_depth-2*pcb_radius-3, 0]) cylinder(h=upper_case_height+0.1, r=pcb_radius+1);
   }
   
   // threaded inserts