diff --git a/GUI_Elbow.py b/GUI_Elbow.py
index 00a1c75567b68b1eaa301993e7af394d4c5209a4..8b75242e11a6e0cc458caa38295b6e64d1f70f20 100644
--- a/GUI_Elbow.py
+++ b/GUI_Elbow.py
@@ -700,11 +700,10 @@ class mainPanel(wx.Panel):
             #
         elif plot_over == 3 and flow.case != "SingleElbow": # this is dl
             x = np.linspace(flow.dl[0],flow.dl[-1],200)
-            y,y_u   = self.interpol_meter(self.Rc,self.dl,self.dist,x)
-            x = x/pi*180
+            y,y_u   = self.interpol_meter(self.Rc,x,self.dist,self.phi)
             xlabel = "angle in grad"
             # the selected x-value from the sliders
-            x_selected = self.phi/pi*180
+            x_selected = self.dl
             #
         else: 
             print("no axes selected")