diff --git a/src/Meshing/Internal.py b/src/Meshing/Internal.py
index d30b2309..016688ed 100644
--- a/src/Meshing/Internal.py
+++ b/src/Meshing/Internal.py
@@ -63,38 +63,29 @@ class InternalMeshing(AMeshingTool):
 
     def st_to_m(self, profiles, guide_list):
 
-        gl1 = [""] + guide_list
-        gl2 = guide_list + [""]
-        max_values = [0] * (len(guide_list) + 1)
-        max_values_index = [0] * (len(guide_list) + 1)
+        guide_list = ["un"] + guide_list + ["np"]
+        max_values = [0] * (len(guide_list) - 1)
+        max_values_index = [0] * (len(guide_list) - 1)
         # we work between each couple of guidelines
         for j, p in enumerate(profiles):
-            index1 = 0
-            index2 = p.named_point_index(guide_list[0])
-            if index2 - index1 > max_values[0]:
-                max_values[0] = index2 - index1
-                max_values_index[0] = j
             for i in range(len(guide_list) - 1):
                 index1 = p.named_point_index(guide_list[i])
                 index2 = p.named_point_index(guide_list[i+1])
-                if index2 - index1 > max_values[i+1]:
-                    max_values[i+1] = index2 - index1
-                    max_values_index[i+1] = j
-            index1 = p.named_point_index(guide_list[-1])
-            index2 = len(p) - 1
-            if index2 - index1 > max_values[-1]:
-                max_values[-1] = index2 - index1
-                max_values_index[-1] = j
+                if index2 - index1 > max_values[i]:
+                    max_values[i] = index2 - index1
+                    max_values_index[i] = j
 
         for i in range(len(max_values)):
             for isect in range(max_values_index[i], len(profiles)-1):
                 self.compl_sect(profiles[isect],
                                 profiles[isect+1],
-                                gl1[i], gl2[i])
+                                guide_list[i],
+                                guide_list[i+1])
             for isect in reversed(range(0, max_values_index[i])):
                 self.compl_sect(profiles[isect+1],
                                 profiles[isect],
-                                gl1[i], gl2[i])
+                                guide_list[i],
+                                guide_list[i+1])
         return profiles
 
     def interpolate_transversal_step(self,
@@ -294,6 +285,8 @@ class InternalMeshing(AMeshingTool):
             sgn = -1.0
         else:
             sgn = old_orientation
+        if abs(sgn) < 0.5:
+            sgn = 1.0
 
         new_rk = [0.0]*nprof
         new_rk[origin] = origin_value
diff --git a/src/Model/Geometry/Profile.py b/src/Model/Geometry/Profile.py
index 04310d8c..462e3467 100644
--- a/src/Model/Geometry/Profile.py
+++ b/src/Model/Geometry/Profile.py
@@ -76,12 +76,23 @@ class Profile(object):
         return self.points[index]
 
     def named_point(self, name):
-        return next((p for p in self.points if p.name == name), None)
+        if name == "un":
+            return self.points[0]
+        elif name == "np":
+            return self.points[-1]
+        else:
+            return next((p for p in self.points if p.name == name), None)
 
     def named_point_index(self, name):
-        return next(
-            (p for p in enumerate(self.points) if p[1].name == name), None
-        )[0]
+        if name == "un":
+            return 0
+        elif name == "np":
+            return len(self.points) - 1
+        else:
+            return next(
+                (p for p in enumerate(self.points) if p[1].name == name),
+                None
+            )[0]
 
     @property
     def reach(self):