diff --git a/ApplicationView/ApplicationController.cs b/ApplicationView/ApplicationController.cs
index 526b5776b..ef1bb5d3d 100644
--- a/ApplicationView/ApplicationController.cs
+++ b/ApplicationView/ApplicationController.cs
@@ -399,7 +399,24 @@ namespace MatterHackers.MatterControl
 			new SceneSelectionOperation()
 			{
 				TitleResolver = () => "Proportional Scale".Localize(),
-				Action = (scene) => HoldChildProportional.AddSelectionAsChildren(scene, nameof(ProportionalEditor), "Proportional Scale"),
+				Action = (scene) =>
+				{
+					HoldChildProportional.AddSelectionAsChildren(scene, new HoldChildProportional(), nameof(ProportionalEditor), "Proportional Scale");
+				},
+				//Icon = AggContext.StaticData.LoadIcon("subtract.png").SetPreMultiply(),
+				IsEnabled = (scene) => scene.HasSelection,
+			},
+			new SceneSelectionOperation()
+			{
+				TitleResolver = () => "Array".Localize(),
+				Action = (scene) =>
+				{
+					HoldChildProportional.AddSelectionAsChildren(scene, new ArrayObject3D(), nameof(ArrayObject3D), "Array Part");
+					if(scene.SelectedItem is ArrayObject3D array)
+					{
+						array.SetCopy();
+					}
+				},
 				//Icon = AggContext.StaticData.LoadIcon("subtract.png").SetPreMultiply(),
 				IsEnabled = (scene) => scene.HasSelection,
 			},
diff --git a/DesignTools/Operations/ArrayObject3D.cs b/DesignTools/Operations/ArrayObject3D.cs
new file mode 100644
index 000000000..a6b2fb24b
--- /dev/null
+++ b/DesignTools/Operations/ArrayObject3D.cs
@@ -0,0 +1,72 @@
+/*
+Copyright (c) 2018, Lars Brubaker, John Lewin
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+The views and conclusions contained in the software and documentation are those
+of the authors and should not be interpreted as representing official policies,
+either expressed or implied, of the FreeBSD Project.
+*/
+
+using System;
+using System.Linq;
+using MatterHackers.DataConverters3D;
+using MatterHackers.VectorMath;
+
+namespace MatterHackers.MatterControl.DesignTools.Operations
+{
+	public class ArrayObject3D : Object3D, IRebuildable
+	{
+		IObject3D item;
+
+		public int Count { get; set; } = 3;
+		public double XOffset { get; set; } = 30;
+		public double YOffset { get; set; } = 30;
+
+		public override string ActiveEditor => "PublicPropertyEditor";
+
+		public ArrayObject3D()
+		{
+		}
+
+		public void Rebuild()
+		{
+			this.Children.Modify(list =>
+			{
+				list.Clear();
+				for(int i=0; i<Count; i++)
+				{
+					var next = item.Clone();
+					next.Matrix = Matrix4X4.CreateTranslation(XOffset * i, YOffset * i, 0);
+					list.Add(next.Clone());
+				}
+			});
+		}
+
+		public void SetCopy()
+		{
+			item = Children.First();
+			Children.Remove(item);
+			Rebuild();
+		}
+	}
+}
\ No newline at end of file
diff --git a/MatterControl.csproj b/MatterControl.csproj
index ae46cdc15..8eccbc4a4 100644
--- a/MatterControl.csproj
+++ b/MatterControl.csproj
@@ -88,6 +88,7 @@
     <Compile Include="DataStorage\ApplicationDataStorage.cs" />
     <Compile Include="DesignTools\Operations\Object3DExtensions.cs" />
     <Compile Include="DesignTools\Operations\Align.cs" />
+    <Compile Include="DesignTools\Operations\ArrayObject3D.cs" />
     <Compile Include="DesignTools\Operations\Scale.cs" />
     <Compile Include="DesignTools\Operations\Rotate.cs" />
     <Compile Include="DesignTools\Operations\SmoothPath.cs" />
diff --git a/PartPreviewWindow/View3D/Actions/ProportionalEditor.cs b/PartPreviewWindow/View3D/Actions/ProportionalEditor.cs
index 80e071e6d..208f0323b 100644
--- a/PartPreviewWindow/View3D/Actions/ProportionalEditor.cs
+++ b/PartPreviewWindow/View3D/Actions/ProportionalEditor.cs
@@ -80,11 +80,10 @@ namespace MatterHackers.MatterControl.PartPreviewWindow.View3D
 			base.OnInvalidate();
 		}
 
-		public static void AddSelectionAsChildren(InteractiveScene scene, string classDescriptor, string editorName)
+		public static void AddSelectionAsChildren(InteractiveScene scene, IObject3D newParent, string classDescriptor, string editorName)
 		{
 			if (scene.HasSelection)
 			{
-				HoldChildProportional newParent = new HoldChildProportional();
 				IObject3D itemToHoldProportional;
 
 				List<IObject3D> itemsToReplace;
@@ -120,7 +119,10 @@ namespace MatterHackers.MatterControl.PartPreviewWindow.View3D
 				newParent.Matrix = itemToHoldProportional.Matrix;
 				itemToHoldProportional.Matrix = Matrix4X4.Identity;
 
-				newParent.InitialChildBounds = itemToHoldProportional.GetAxisAlignedBoundingBox();
+				if (newParent is HoldChildProportional pe)
+				{
+					pe.InitialChildBounds = itemToHoldProportional.GetAxisAlignedBoundingBox();
+				}
 
 				scene.SelectedItem = newParent;
 			}