diff --git a/TextCanvas.py b/TextCanvas.py
index 842ce71..f012621 100644
--- a/TextCanvas.py
+++ b/TextCanvas.py
@@ -105,7 +105,8 @@ class TextCanvas:
 		# So far simply does maintenance once per second
 		while self.__conveyor_enabled is True:
 			
-			self.__fps_samples.append(0)
+			with RAIILock(self.__lock):
+				self.__fps_samples.append(0)
 			
 			time.sleep(1)