diff --git a/plaster.py b/plaster.py
index f70a83d..53b82ad 100644
--- a/plaster.py
+++ b/plaster.py
@@ -3327,7 +3327,7 @@ class plotter_gcode(inkex.Effect):
         if self.options.coordinates_unit == "MM": 
             points = [[0.,0.,0.],[100.,0.,0.],[0.,100.,0.]]
             #2019.08.08 - geaendert (Mario Voigt) orientation_scale = 3.5433070660
-            orientation_scale = 1.0
+            orientation_scale = 3.5433070660
             print_("orientation_scale < 0 ===> switching to mm units=%0.10f"%orientation_scale )
         elif self.options.coordinates_unit == "IN":
             points = [[0.,0.,0.],[5.,0.,0.],[0.,5.,0.]]