diff --git a/pylabrobot/liquid_handling/backends/hamilton/STAR_backend.py b/pylabrobot/liquid_handling/backends/hamilton/STAR_backend.py
index 4a233f07a27..2bde0dc43bf 100644
--- a/pylabrobot/liquid_handling/backends/hamilton/STAR_backend.py
+++ b/pylabrobot/liquid_handling/backends/hamilton/STAR_backend.py
@@ -4974,6 +4974,7 @@ async def dispense_pip(
   @need_iswap_parked
   async def get_core(self, p1: int, p2: int):
     """Get CoRe gripper tool from wasteblock mount."""
+
     if not 0 <= p1 < self.num_channels:
       raise ValueError(f"channel_1 must be between 0 and {self.num_channels - 1}")
     if not 1 <= p2 <= self.num_channels:
@@ -4984,23 +4985,29 @@ async def get_core(self, p1: int, p2: int):
     # a resource on the robot deck and use deck.get_resource().get_location_wrt(self.deck).
     deck_size = self.deck.get_absolute_size_x()
     if deck_size == STARLET_SIZE_X:
-      xs = 7975  # 1360-797.5 = 562.5
+      xs = 7975  # 1360-797.5 = 562.5 (distance to right edge of deck)
     elif deck_size == STAR_SIZE_X:
-      xs = 13385  # 1900-1337.5 = 562.5, plus a manual adjustment of + 10
+      xs = 13375  # 1900-1337.5 = 562.5 (distance to right edge of deck)
     else:
       raise ValueError(f"Deck size {deck_size} not supported")
 
+    channel_x_coord = round(xs + self.core_adjustment.x * 10)
+    back_channel_y_center = round(1250 + self.core_adjustment.y * 10)
+    front_channel_y_center = round(1070 + self.core_adjustment.y * 10)
+    begin_z_coord = round(2350 + self.core_adjustment.z * 10)
+    end_z_coord = round(2250 + self.core_adjustment.z * 10)
+
     command_output = await self.send_command(
       module="C0",
       command="ZT",
-      xs=f"{xs + self.core_adjustment.x:05}",
+      xs=f"{channel_x_coord:05}",
       xd="0",
-      ya=f"{1240 + self.core_adjustment.y:04}",
-      yb=f"{1065 + self.core_adjustment.y:04}",
+      ya=f"{back_channel_y_center:04}",
+      yb=f"{front_channel_y_center:04}",
       pa=f"{p1:02}",
       pb=f"{p2:02}",
-      tp=f"{2350 + self.core_adjustment.z:04}",
-      tz=f"{2250 + self.core_adjustment.z:04}",
+      tp=f"{begin_z_coord:04}",
+      tz=f"{end_z_coord:04}",
       th=round(self._iswap_traversal_height * 10),
       tt="14",
     )
@@ -5010,23 +5017,32 @@ async def get_core(self, p1: int, p2: int):
   @need_iswap_parked
   async def put_core(self):
     """Put CoRe gripper tool at wasteblock mount."""
+
     assert self.deck is not None, "must have deck defined to access CoRe grippers"
+
     deck_size = self.deck.get_absolute_size_x()
     if deck_size == STARLET_SIZE_X:
       xs = 7975
     elif deck_size == STAR_SIZE_X:
-      xs = 13385
+      xs = 13375
     else:
       raise ValueError(f"Deck size {deck_size} not supported")
+
+    channel_x_coord = round(xs + self.core_adjustment.x * 10)
+    back_channel_y_center = round(1240 + self.core_adjustment.y * 10)
+    front_channel_y_center = round(1065 + self.core_adjustment.y * 10)
+    begin_z_coord = round(2150 + self.core_adjustment.z * 10)
+    end_z_coord = round(2050 + self.core_adjustment.z * 10)
+
     command_output = await self.send_command(
       module="C0",
       command="ZS",
-      xs=f"{xs + self.core_adjustment.x:05}",
+      xs=f"{channel_x_coord:05}",
       xd="0",
-      ya=f"{1240 + self.core_adjustment.y:04}",
-      yb=f"{1065 + self.core_adjustment.y:04}",
-      tp=f"{2150 + self.core_adjustment.z:04}",
-      tz=f"{2050 + self.core_adjustment.z:04}",
+      ya=f"{back_channel_y_center:04}",
+      yb=f"{front_channel_y_center:04}",
+      tp=f"{begin_z_coord:04}",
+      tz=f"{end_z_coord:04}",
       th=round(self._iswap_traversal_height * 10),
       te=round(self._iswap_traversal_height * 10),
     )
diff --git a/pylabrobot/liquid_handling/backends/hamilton/STAR_tests.py b/pylabrobot/liquid_handling/backends/hamilton/STAR_tests.py
index fd2cba3b370..a2f3b5ec7a8 100644
--- a/pylabrobot/liquid_handling/backends/hamilton/STAR_tests.py
+++ b/pylabrobot/liquid_handling/backends/hamilton/STAR_tests.py
@@ -927,7 +927,7 @@ async def test_move_core(self):
     self.STAR._write_and_read_command.assert_has_calls(
       [
         _any_write_and_read_command_call(
-          "C0ZTid0001xs07975xd0ya1240yb1065pa07pb08tp2350tz2250th2800tt14"
+          "C0ZTid0001xs07975xd0ya1250yb1070pa07pb08tp2350tz2250th2800tt14"
         ),
         _any_write_and_read_command_call(
           "C0ZPid0002xs03479xd0yj1142yv0050zj1876zy0500yo0885yg0825yw15" "th2800te2800"