diff --git a/interp/grid/__init__.py b/interp/grid/__init__.py
index cc1f0c1..3e989da 100644
--- a/interp/grid/__init__.py
+++ b/interp/grid/__init__.py
@@ -50,7 +50,7 @@ class grid(object):
 
     simplex = None
     checked_faces = []
-    faces_to_check = self.faces_for_vert[closest_point]
+    faces_to_check = list(self.faces_for_vert[closest_point])
 
     attempts = 0
     while not simplex and faces_to_check:
@@ -66,14 +66,14 @@ class grid(object):
         simplex = cur_face
         continue
 
-      new_facest = []
       for neighbor in cur_face.neighbors:
         if (neighbor not in checked_faces) and (neighbor not in faces_to_check):
           faces_to_check.append(neighbor)
 
     if not simplex:
-      raise AssertionError('no containing simplex found')
+      raise Exception('no containing simplex found')
 
+    log.debug("simplex vert indicies: %s" % simplex.verts)
     R = self.create_mesh(simplex.verts)
 
     log.debug('total attempts before finding simplex: %d' % attempts)
@@ -106,7 +106,7 @@ class grid(object):
 
     # and some UNIQUE extra verts
     (dist, indicies) = self.tree.query(X, simplex_size + extra_points)
-    log.info("extra indicies: %s" % indicies)
+    log.debug("extra indicies: %s" % indicies)
 
     unique_indicies = []
     for index in indicies:
@@ -196,13 +196,12 @@ class delaunay_grid(grid):
         simplex = cur_face
         continue
 
-      new_facest = []
       for neighbor in cur_face.neighbors:
         if (neighbor not in checked_faces) and (neighbor not in faces_to_check):
           faces_to_check.append(neighbor)
 
     if not simplex:
-      raise AssertionError('no containing simplex found')
+      raise Exception('no containing simplex found')
 
     R = self.create_mesh(simplex.verts)