diff --git a/game.py b/game.py
index 3b6d093..ded8f53 100644
--- a/game.py
+++ b/game.py
@@ -2040,6 +2040,13 @@ def process_player(world: dict, player: dict, now: float, rng: random.Random | N
                     summary["resumed"] = back
                 else:
                     stop(player)
+        if player["action"] is current and "enemy" not in action and not current.get("plot2"):
+            # Out of materials: stop now, not once the next bar has filled.
+            reason = can_start(world, player, growing(player))
+            if reason:
+                stop(player, reason)
+                summary["stopped"] = reason
+                break
     if player["action"] and limit < now and current["start"] < now:
         current["start"] = now
     return summary
diff --git a/tests/test_game.py b/tests/test_game.py
index 5dd9d0a..3758751 100644
--- a/tests/test_game.py
+++ b/tests/test_game.py
@@ -91,6 +91,16 @@ class ActionTest(unittest.TestCase):
         self.assertIsNone(p["action"])
         self.assertEqual(summary["stopped"], "Out of copper ore")
 
+    def test_crafting_stops_as_the_last_one_finishes(self):
+        world = world_with(("ann", "commoner"))
+        p = world["players"]["ann"]
+        p["bank"] = {"copper_ore": 1, "logs": 10}
+        game.start_action(world, p, "smith_copper_bar", T0)
+        duration = game.action_time(world, p, game.ACTION_BY_ID["smith_copper_bar"])
+        summary = game.process_player(world, p, T0 + duration + 0.1, random.Random(1))
+        self.assertIsNone(p["action"])
+        self.assertEqual(summary["stopped"], "Out of copper ore")
+
     def test_level_and_city_requirements(self):
         world = world_with(("ann", "commoner"))
         p = world["players"]["ann"]