diff --git a/scripts/SANS/sans/gui_logic/models/RowEntries.py b/scripts/SANS/sans/gui_logic/models/RowEntries.py
index 1e1b84db1780d4e100db21f8024216e6bec3a2b7..0b76fac2d9a4f6fe38faff8ee74d2f25fb3b294b 100644
--- a/scripts/SANS/sans/gui_logic/models/RowEntries.py
+++ b/scripts/SANS/sans/gui_logic/models/RowEntries.py
@@ -82,7 +82,11 @@ class RowEntries(_UserEntries):
 
     @sample_shape.setter
     def sample_shape(self, val):
-        if val is SampleShape:
+        if not val:
+            self._sample_shape = None
+            return
+
+        if isinstance(val, SampleShape):
             self._sample_shape = val
             return