diff --git a/cad/build.py b/cad/build.py
index 76cd55d..56c3cb8 100644
--- a/cad/build.py
+++ b/cad/build.py
@@ -119,7 +119,7 @@ def build_drive_shaft_bar_adapter():
 
         # extrusion screw holes
         with Locations((0, 0, height - ext_screw_hole_offset)):
-            with PolarLocations(4, 4):
+            with PolarLocations(0, 4):
                 with Locations(Rotation(0, 90, 0)):
                     Hole(ext_screw_hole_diam / 2)
 
@@ -129,7 +129,7 @@ def build_drive_shaft_bar_adapter():
             with Locations((-l, -l), (-l, l), (l, -l), (l, l)):
                 CounterBoreHole(shaft_hub_screw_diam / 2, shaft_hub_screw_head_diam / 2, shaft_hub_screw_head_depth, thickness + shaft_hub_screw_depth)
         with Locations(drive_shaft_bar_adapter.faces().sort_by(Axis.Z)[0].center()):
-            Hole(shaft_hub_bore_diam / 2)
+            Hole((shaft_hub_bore_diam + 0.5) / 2)
             Hole(shaft_hub_center_diam / 2, shaft_hub_center_depth)
 
     return drive_shaft_bar_adapter