diff --git a/cad/build.py b/cad/build.py
index a84b0f7..b7445de 100644
--- a/cad/build.py
+++ b/cad/build.py
@@ -85,6 +85,35 @@ def build_drive_shaft_mount():
 
     return drive_shaft_mount
 
+def build_drive_shaft_bar_adapter():
+    extrusion_size = 20
+
+    height = 60
+    thickness = 10
+
+    with BuildPart() as drive_shaft_bar_adapter_slice:
+        with BuildSketch(Plane.XZ.offset(extrusion_size / -2)):
+            Rectangle(extrusion_size + (thickness * 2), height, align=(Align.CENTER, Align.MIN))
+
+            with Locations((0, height - 10)):
+                Circle(5, mode=Mode.SUBTRACT)
+
+        extrude(amount=-thickness)
+
+        Box(extrusion_size / 2, extrusion_size / 2, thickness, align=(Align.MIN, Align.MIN, Align.MIN))
+        with Locations((8, 8, 0)):
+            Hole(4)
+
+    with BuildPart() as drive_shaft_bar_adapter:
+        with PolarLocations(0, 4):
+            add(drive_shaft_bar_adapter_slice)
+
+    return drive_shaft_bar_adapter
+
 drive_shaft_mount = build_drive_shaft_mount()
 assert drive_shaft_mount.part is not None
 export_step(drive_shaft_mount.part, "drive shaft mount.step")
+
+drive_shaft_bar_adapter = build_drive_shaft_bar_adapter()
+assert drive_shaft_bar_adapter.part is not None
+export_step(drive_shaft_bar_adapter.part, "drive shaft bar adapter.step")