diff --git a/src/openflexure_microscope_server/things/stage/__init__.py b/src/openflexure_microscope_server/things/stage/__init__.py
index 3298e2ac..d0bdeab6 100644
--- a/src/openflexure_microscope_server/things/stage/__init__.py
+++ b/src/openflexure_microscope_server/things/stage/__init__.py
@@ -147,7 +147,7 @@ class BaseStage(lt.Thing):
         return self._apply_axis_direction(self._hardware_position)
 
     backlash_steps: dict[str, int] = lt.setting(
-        default={"x": 200, "y": 200, "z": 200}, readonly=True
+        default_factory=lambda: {"x": 200, "y": 200, "z": 200}, readonly=True
     )
     """The number of steps to elimate backlash. The sign sets the direction.
 
@@ -161,7 +161,7 @@ class BaseStage(lt.Thing):
     """Whether the stage is in motion."""
 
     axis_inverted: dict[str, bool] = lt.setting(
-        default={"x": False, "y": False, "z": False}, readonly=True
+        default_factory=lambda: {"x": False, "y": False, "z": False}, readonly=True
     )
     """Used to convert coordinates between the program frame and the hardware frame."""
 
diff --git a/src/openflexure_microscope_server/things/stage/dummy.py b/src/openflexure_microscope_server/things/stage/dummy.py
index 4948d266..c1b0e5c5 100644
--- a/src/openflexure_microscope_server/things/stage/dummy.py
+++ b/src/openflexure_microscope_server/things/stage/dummy.py
@@ -77,7 +77,7 @@ class DummyStage(BaseStage):
             self._move_thread.join()
 
     axis_inverted: dict[str, bool] = lt.setting(
-        default={"x": True, "y": False, "z": False}, readonly=True
+        default_factory=lambda: {"x": True, "y": False, "z": False}, readonly=True
     )
     """Used to convert coordinates between the program frame and the hardware frame."""
 
diff --git a/src/openflexure_microscope_server/things/stage/sangaboard.py b/src/openflexure_microscope_server/things/stage/sangaboard.py
index a6c99eb9..b8ad994c 100644
--- a/src/openflexure_microscope_server/things/stage/sangaboard.py
+++ b/src/openflexure_microscope_server/things/stage/sangaboard.py
@@ -76,7 +76,7 @@ class SangaboardThing(BaseStage):
             self._sangaboard.close()
 
     axis_inverted: dict[str, bool] = lt.setting(
-        default={"x": True, "y": False, "z": True}, readonly=True
+        default_factory=lambda: {"x": True, "y": False, "z": True}, readonly=True
     )
     """Used to convert coordinates between the program frame and the hardware frame."""