diff --git a/src/dtm.adb b/src/dtm.adb
index 7282b60..5c538c2 100644
--- a/src/dtm.adb
+++ b/src/dtm.adb
@@ -22,18 +22,22 @@ package body Dtm is
       return Max_Val;
    end Max;
 
-   procedure Scale(Data : in out Dtm_Data; Scale_Factor : Dtm_Value := 100.0) is
+   function "+"(D : Dtm_Data; V : Dtm_Value) return Dtm_Data is
+      R : Dtm_Data := D;
    begin
-      for Element of Data.Grid loop
-            Element := Element * Scale_Factor;
+      for El of R.Grid loop
+         El := El + V;
       end loop;
-   end Scale;
+      return R;
+   end;
 
-   procedure Pad(Data :in out Dtm_Data; Pad_Factor : Dtm_Value := 2.0) is
+   function "*"(D : Dtm_Data; V : Dtm_Value) return Dtm_Data is
+      R : Dtm_Data := D;
    begin
-      for Element of Data.Grid loop
-         Element := Element + Pad_Factor;
+      for El of R.Grid loop
+         El := El * V;
       end loop;
+      return R;
    end;
 
    function Triangle_Count(Info : Dtm_Info) return Natural is
diff --git a/src/dtm.ads b/src/dtm.ads
index c7b7962..25cb127 100644
--- a/src/dtm.ads
+++ b/src/dtm.ads
@@ -12,9 +12,9 @@ package Dtm with SPARK_Mode is
      Global => null;
    
    function Max(Data : Dtm_Data) return Dtm_Value;
-   procedure Scale(Data : in out Dtm_Data; Scale_Factor : Dtm_Value := 100.0);
-   procedure Pad(Data :in out Dtm_Data; Pad_Factor : Dtm_Value := 2.0);
    function Triangle_Count(Info : Dtm_Info) return Natural;
+   function "+"(D : Dtm_Data; V : Dtm_Value) return Dtm_Data;
+   function "*"(D : Dtm_Data; V : Dtm_Value) return Dtm_Data;
    
 private
    type Dtm_Data(X, Y : Integer) is tagged
diff --git a/src/tess.adb b/src/tess.adb
index 6b8142b..8b5c534 100644
--- a/src/tess.adb
+++ b/src/tess.adb
@@ -10,8 +10,8 @@ procedure Tess is
    use Ada.Text_IO;
    Info : Dtm_Info;
    Input : File_Type;
-   Minimum_Thickness : constant := 2.0;
-   Z_Scaling_Value : constant := 100.0;
+   Minimum_Thickness : constant := 1.0;
+   Z_Scaling_Value : constant := 20.0;
 begin
    Ada.Text_IO.Put_Line("Tess started.");
    Open(Input, In_File, "sample-data/katie.dat");
@@ -27,11 +27,11 @@ begin
    begin
       Dtm.Katie.Get_Data(Data, Input);
       Normalize_and_Scale_Factor := Z_Scaling_Value / Max(Data);
-      Data.Scale(Normalize_and_Scale_Factor);
-      Data.Pad(Minimum_Thickness);
+      Data := Data * Normalize_and_Scale_Factor;
+      Data := Data + Minimum_Thickness;
       Triangles.Reserve_Capacity(Count_Type(Info.Triangle_Count));
       Dtm.Surface.Surface_From_Grid(Triangles, Data);
-      Stl.Write(Triangles, "Farts.stl");
+      -- Stl.Write(Triangles, "Farts.stl");
       Stl.Write_Binary(Triangles, "Binary_Farts.stl");
    end;
 end Tess;