diff --git a/Assets/Scripts/tools/Extruder.cs b/Assets/Scripts/tools/Extruder.cs
index 657baa1a..ee1dda31 100644
--- a/Assets/Scripts/tools/Extruder.cs
+++ b/Assets/Scripts/tools/Extruder.cs
@@ -19,9 +19,7 @@
 using com.google.apps.peltzer.client.model.controller;
 using com.google.apps.peltzer.client.model.core;
 using com.google.apps.peltzer.client.model.main;
-using com.google.apps.peltzer.client.model.util;
 using com.google.apps.peltzer.client.model.render;
-using com.google.apps.peltzer.client.tools.utils;
 
 namespace com.google.apps.peltzer.client.tools
 {
@@ -30,7 +28,7 @@ namespace com.google.apps.peltzer.client.tools
     ///   Update() loop.
     ///   An extrusion is composed of grabbing a face, (potentially) pulling out the face, and releasing. The face
     ///   itself is moved, and new faces are created to link the moved face back to the mesh.
-    ///  
+    ///
     /// </summary>
     public class Extruder : MonoBehaviour
     {
@@ -72,7 +70,7 @@ public class Extruder : MonoBehaviour
 
         private WorldSpace worldSpace;
 
-        // Detection for trigger down & straight back up, vs trigger down and hold -- either of which 
+        // Detection for trigger down & straight back up, vs trigger down and hold -- either of which
         // begins an extrusion.
         private bool triggerUpToRelease;
         private float triggerDownTime;
@@ -108,7 +106,7 @@ public void Setup(Model model, ControllerMain controllerMain, PeltzerController
             controllerMain.ControllerActionHandler += ControllerEventHandler;
         }
 
-        private ExtrusionOperation.ExtrusionParams BuildExtrusionParams(bool flipped)
+        private ExtrusionOperation.ExtrusionParams BuildExtrusionParams(bool flipped, bool multi)
         {
             // Note: ExtrusionParams is a struct, so this is stack allocated and doesn't generate garbage.
             ExtrusionOperation.ExtrusionParams extrusionParams = new ExtrusionOperation.ExtrusionParams();
@@ -119,6 +117,7 @@ private ExtrusionOperation.ExtrusionParams BuildExtrusionParams(bool flipped)
             extrusionParams.rotationModel =
               peltzerController.LastRotationModel * Quaternion.Inverse(extrusionBeginOrientation);
             extrusionParams.flipped = flipped;
+            extrusionParams.multipleFaces = multi;
             return extrusionParams;
         }
 
@@ -182,7 +181,7 @@ private void Update()
                     var dragVector = peltzerController.LastPositionModel - extrusionBeginPosition;
                     towards = Vector3.Dot(faceVector, dragVector) > 0;
                 }
-                ExtrusionOperation.ExtrusionParams extrusionParams = BuildExtrusionParams(!towards);
+                ExtrusionOperation.ExtrusionParams extrusionParams = BuildExtrusionParams(!towards, extrusions.Count > 1);
                 foreach (ExtrusionOperation operation in extrusions)
                 {
                     operation.UpdateExtrudeGuide(extrusionParams);
@@ -415,7 +414,7 @@ private void ReleaseMesh()
                 var dragVector = peltzerController.LastPositionModel - extrusionBeginPosition;
                 towards = Vector3.Dot(faceVector, dragVector) > 0;
             }
-            ExtrusionOperation.ExtrusionParams extrusionParams = BuildExtrusionParams(!towards);
+            ExtrusionOperation.ExtrusionParams extrusionParams = BuildExtrusionParams(!towards, extrusions.Count > 1);
 
             foreach (ExtrusionOperation extrusion in extrusions)
             {
@@ -464,7 +463,7 @@ private void ReleaseMesh()
                 }
             }
 
-            // Expire the temporary held face commands, because the originally-held faces have now been removed 
+            // Expire the temporary held face commands, because the originally-held faces have now been removed
             // following a successful extrusion.
             temporaryHeldFaceMaterialCommands.Clear();
             model.ApplyCommand(new CompositeCommand(commands));
diff --git a/Assets/Scripts/tools/ExtrusionOperation.cs b/Assets/Scripts/tools/ExtrusionOperation.cs
index 5c632a65..84adb1c0 100644
--- a/Assets/Scripts/tools/ExtrusionOperation.cs
+++ b/Assets/Scripts/tools/ExtrusionOperation.cs
@@ -50,6 +50,7 @@ public struct ExtrusionParams
         // This is in MODEL space.
         public Vector3 rotationPivotModel;
         public bool flipped;
+        public bool multipleFaces;
     }
 
     /// <summary>
@@ -476,8 +477,22 @@ public static List<ExtrusionSideVertices> BuildExtrusionSides(
         Vector3 projectedDelta;
         if (extrusionParams.lockToNormal)
         {
-            var extrudedPoint = GridUtils.SnapToGrid(extrusionParams.translationModel);
-            projectedDelta = mesh.rotation * face.normal * (extrudedPoint.magnitude * (extrusionParams.flipped ? -1 : 1));
+            if (extrusionParams.multipleFaces)
+            {
+                var extrudedPoint = GridUtils.SnapToGrid(extrusionParams.translationModel);
+                projectedDelta = mesh.rotation * face.normal * (extrudedPoint.magnitude * (extrusionParams.flipped ? -1 : 1));
+            }
+            else
+            {
+                List<Vector3> coplanar = new List<Vector3> {
+                    mesh.VertexPositionInModelCoords(face.vertexIds[0]),
+                    mesh.VertexPositionInModelCoords(face.vertexIds[1]),
+                    mesh.VertexPositionInModelCoords(face.vertexIds[2])
+                };
+                Vector3 normal = MeshMath.CalculateNormal(coplanar);
+                projectedDelta =
+                    Vector3.Project(GridUtils.SnapToGrid(extrusionParams.translationModel), normal);
+            }
         }
         else
         {