diff --git a/gantry.py b/gantry.py
index e6e4011..bd9f494 100644
--- a/gantry.py
+++ b/gantry.py
@@ -341,21 +341,42 @@ class Carriage:
 
         self.ball_nut = gantry.ball_screw_model.nut(x + carriage_w / 2)
 
+        lbolster_w = self.plate.workplaneFromTagged("carriage_plate").transformed(
+            offset=(-(carriage_w - bolster_w) / 2, 0, 0)
+        )
+        rbolster_w = self.plate.workplaneFromTagged("carriage_plate").transformed(
+            offset=((carriage_w - bolster_w) / 2, 0, 0)
+        )
+
+        points = [(0, 50 * (i - 2.5)) for i in range(6)]
+
         self.lbolster = (
             cq.Workplane()
-            .copyWorkplane(self.plate.workplaneFromTagged("carriage_plate"))
-            .transformed(offset=(-(carriage_w - bolster_w) / 2, 0, 0))
+            .copyWorkplane(lbolster_w)
             .rect(bolster_w, carriage_h)
             .extrude(bolster_z)
+            .copyWorkplane(lbolster_w.transformed(rotate=(0, 180, 0)))
+            .pushPoints(points)
+            .hole(3)
         )
         self.rbolster = (
             cq.Workplane()
-            .copyWorkplane(self.plate.workplaneFromTagged("carriage_plate"))
-            .transformed(offset=((carriage_w - bolster_w) / 2, 0, 0))
+            .copyWorkplane(rbolster_w)
             .rect(bolster_w, carriage_h)
             .extrude(bolster_z)
+            .copyWorkplane(lbolster_w.transformed(rotate=(0, 180, 0)))
+            .pushPoints(points)
+            .hole(3)
+        )
+
+        self.plate = (
+            self.plate.copyWorkplane(lbolster_w)
+            .pushPoints(points)
+            .hole(3)
+            .copyWorkplane(rbolster_w)
+            .pushPoints(points)
+            .hole(3)
         )
-        # TODO add bolster mounting holes
 
         self.wp_carrier = (
             cq.Workplane()