diff --git a/vedo/assembly.py b/vedo/assembly.py
index 2c2c4a91..2f944ef1 100644
--- a/vedo/assembly.py
+++ b/vedo/assembly.py
@@ -137,7 +137,7 @@ def __iadd__(self, obj):
             if a:
                 try:
                     self.AddPart(a)
-                except AttributeError:
+                except TypeError:
                     self.AddPart(a.actor)
         return self