diff --git a/Machining/DemoBuildMachiningProject.cs b/Machining/DemoBuildMachiningProject.cs
index 35d4af8..2a24cc1 100644
--- a/Machining/DemoBuildMachiningProject.cs
+++ b/Machining/DemoBuildMachiningProject.cs
@@ -61,7 +61,7 @@ namespace Sample.Machining
                     }),
                 UpperBeamGeom = new ExtendedCylinder(90),
                 InnerBeamProfile = new FluteDependentRatioProfile(),
-                MillingCutterOptLimit = new MillingCutterOptLimit(),
+                MillingCutterOptLimit = new MillingCutterOptOption(),
             };
             //build FluteContourTray property 
             double helixAngle_deg = 50;
@@ -107,7 +107,7 @@ namespace Sample.Machining
                 UpperBeamGeom = new Cylindroid(
                     [new PairZr(40, 6), new PairZr(90, 6)]),
                 InnerBeamProfile = new FluteDependentRatioProfile(),
-                MillingCutterOptLimit = new MillingCutterOptLimit()
+                MillingCutterOptLimit = new MillingCutterOptOption()
             };
 
             //build FluteContourTray property