diff --git a/OSCADSharp/OSCADSharp.ConsoleTests/Program.cs b/OSCADSharp/OSCADSharp.ConsoleTests/Program.cs
index 19291b8..c1b74b7 100644
--- a/OSCADSharp/OSCADSharp.ConsoleTests/Program.cs
+++ b/OSCADSharp/OSCADSharp.ConsoleTests/Program.cs
@@ -14,8 +14,8 @@ namespace OSCADSharp.ConsoleTests
         static void Main(string[] args)
         {
 
-            var obj = new Cube(5, 5, 20)
-                .Translate(30, 0, 0).Rotate(0, 90, 0).Resize(2, 2, 2);
+            Settings.Globals["$fn"] = 100;
+            var obj = new Sphere(30);
 
             var pos = obj.Position();
             var cyl1 = new Cylinder(1, 100, true).Translate(pos);
@@ -23,10 +23,10 @@ namespace OSCADSharp.ConsoleTests
             var cyl3 = new Cylinder(1, 100, true).Rotate(90, 0, 0).Translate(pos);
             var axisHelper = cyl1.Union(cyl2, cyl3).Color("Red");
 
-            var topCorner = new Sphere().Translate(obj.Bounds().TopRight);
-            var botCorner = new Sphere().Translate(obj.Bounds().BottomLeft);
+            //var topCorner = new Sphere().Translate(obj.Bounds().TopRight);
+            //var botCorner = new Sphere().Translate(obj.Bounds().BottomLeft);
 
-            (obj + topCorner + botCorner + axisHelper).ToFile("test.scad");
+            (obj + axisHelper).ToFile("test.scad");
             
             //Console.ReadKey();
         }
diff --git a/OSCADSharp/OSCADSharp.UnitTests/OSCADObjectTests.cs b/OSCADSharp/OSCADSharp.UnitTests/OSCADObjectTests.cs
index e64a2a8..de5cb5f 100644
--- a/OSCADSharp/OSCADSharp.UnitTests/OSCADObjectTests.cs
+++ b/OSCADSharp/OSCADSharp.UnitTests/OSCADObjectTests.cs
@@ -1,4 +1,6 @@
 using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Moq;
+using OSCADSharp.Scripting;
 using OSCADSharp.Solids;
 using System;
 using System.Collections.Concurrent;
@@ -135,6 +137,39 @@ namespace OSCADSharp.UnitTests
             Assert.AreEqual("Text", children[0].Name);
             Assert.AreEqual("Union", children[1].Name);
         }
+
+        [TestMethod]
+        public void OSCADObject_ToFileIncludesOSCADSharpGeneratedHeader()
+        {
+            var cube = new Cube();
+            string[] output = null;
+
+            var mock = new Mock<IFileWriter>();
+            mock.Setup(_wrtr => _wrtr.WriteAllLines(It.IsAny<string>(), It.IsAny<string[]>()))
+                .Callback<string, string[]>((path, contents) => { output = contents; });
+            Settings.FileWriter = mock.Object;
+
+            cube.ToFile("myFile");
+
+            Assert.AreEqual(Settings.OSCADSharpHeader, output[0]);
+       }
+
+        [TestMethod]
+        public void OSCADObject_ToFileIncludesGlobalVariablesDefinedInSettings()
+        {
+            var cube = new Cube();
+            string[] output = null;
+            Settings.Globals["$fn"] = 100;
+
+            var mock = new Mock<IFileWriter>();
+            mock.Setup(_wrtr => _wrtr.WriteAllLines(It.IsAny<string>(), It.IsAny<string[]>()))
+                .Callback<string, string[]>((path, contents) => { output = contents; });
+            Settings.FileWriter = mock.Object;
+
+            cube.ToFile("myFile");
+
+            Assert.AreEqual("$fn = 100;\r\n", output[1]);
+        }
     }
 }
 
diff --git a/OSCADSharp/OSCADSharp.UnitTests/OSCADSharp.UnitTests.csproj b/OSCADSharp/OSCADSharp.UnitTests/OSCADSharp.UnitTests.csproj
index a1e5ecc..83c374d 100644
--- a/OSCADSharp/OSCADSharp.UnitTests/OSCADSharp.UnitTests.csproj
+++ b/OSCADSharp/OSCADSharp.UnitTests/OSCADSharp.UnitTests.csproj
@@ -35,6 +35,10 @@
     <WarningLevel>4</WarningLevel>
   </PropertyGroup>
   <ItemGroup>
+    <Reference Include="Moq, Version=4.2.1510.2205, Culture=neutral, PublicKeyToken=69f491c39445e920, processorArchitecture=MSIL">
+      <HintPath>..\packages\Moq.4.2.1510.2205\lib\net40\Moq.dll</HintPath>
+      <Private>True</Private>
+    </Reference>
     <Reference Include="System" />
   </ItemGroup>
   <Choose>
@@ -75,6 +79,9 @@
       <Name>OSCADSharp</Name>
     </ProjectReference>
   </ItemGroup>
+  <ItemGroup>
+    <None Include="packages.config" />
+  </ItemGroup>
   <Choose>
     <When Condition="'$(VisualStudioVersion)' == '10.0' And '$(IsCodedUITest)' == 'True'">
       <ItemGroup>
diff --git a/OSCADSharp/OSCADSharp.UnitTests/Solids/CylinderTests.cs b/OSCADSharp/OSCADSharp.UnitTests/Solids/CylinderTests.cs
index b1acbce..5e441f5 100644
--- a/OSCADSharp/OSCADSharp.UnitTests/Solids/CylinderTests.cs
+++ b/OSCADSharp/OSCADSharp.UnitTests/Solids/CylinderTests.cs
@@ -57,5 +57,34 @@ namespace OSCADSharp.UnitTests
             Assert.AreEqual(new Vector3(2.5, 2.5, 10), obj.Bounds().TopRight);
             Assert.AreEqual(new Vector3(-2.5, -2.5, -10), obj.Bounds().BottomLeft);
         }
+
+        [TestMethod]
+        public void Cylinder_ScriptOutputDoesNotContainResolutionValuesIfNotSpecified()
+        {
+            var cylinder = new Cylinder();
+
+            string script = cylinder.ToString();
+
+            Assert.IsTrue(!script.Contains("$fn"));
+            Assert.IsTrue(!script.Contains("$fa"));
+            Assert.IsTrue(!script.Contains("$fs"));
+        }
+
+        [TestMethod]
+        public void Cylinder_ScriptOutpuHasResolutionValuesIfSpecified()
+        {
+            var cylinder = new Cylinder()
+            {
+                Resolution = 40,
+                MinimumAngle = 5,
+                MinimumCircumferentialLength = 2
+            };
+
+            string script = cylinder.ToString();
+
+            Assert.IsTrue(script.Contains("$fn"));
+            Assert.IsTrue(script.Contains("$fa"));
+            Assert.IsTrue(script.Contains("$fs"));
+        }
     }
 }
diff --git a/OSCADSharp/OSCADSharp.UnitTests/Solids/SphereTests.cs b/OSCADSharp/OSCADSharp.UnitTests/Solids/SphereTests.cs
index 2cc55d3..e0c5509 100644
--- a/OSCADSharp/OSCADSharp.UnitTests/Solids/SphereTests.cs
+++ b/OSCADSharp/OSCADSharp.UnitTests/Solids/SphereTests.cs
@@ -86,5 +86,34 @@ namespace OSCADSharp.UnitTests
             Assert.AreEqual(new Vector3(15, 15, 15), obj.Bounds().TopRight);
             Assert.AreEqual(new Vector3(-15, -15, -15), obj.Bounds().BottomLeft);
         }
+
+        [TestMethod]
+        public void Sphere_ScriptOutputDoesNotContainResolutionValuesIfNotSpecified()
+        {
+            var sphere = new Sphere();
+
+            string script = sphere.ToString();
+
+            Assert.IsTrue(!script.Contains("$fn"));
+            Assert.IsTrue(!script.Contains("$fa"));
+            Assert.IsTrue(!script.Contains("$fs"));
+        }
+
+        [TestMethod]
+        public void Sphere_ScriptOutpuHasResolutionValuesIfSpecified()
+        {
+            var sphere = new Sphere()
+            {
+                Resolution = 40,
+                MinimumAngle = 5,
+                MinimumFragmentSize = 2
+            };
+
+            string script = sphere.ToString();
+
+            Assert.IsTrue(script.Contains("$fn"));
+            Assert.IsTrue(script.Contains("$fa"));
+            Assert.IsTrue(script.Contains("$fs"));
+        }
     }
 }
diff --git a/OSCADSharp/OSCADSharp.UnitTests/packages.config b/OSCADSharp/OSCADSharp.UnitTests/packages.config
new file mode 100644
index 0000000..f8429b5
--- /dev/null
+++ b/OSCADSharp/OSCADSharp.UnitTests/packages.config
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="Moq" version="4.2.1510.2205" targetFramework="net452" />
+</packages>
\ No newline at end of file
diff --git a/OSCADSharp/OSCADSharp/OSCADObject.cs b/OSCADSharp/OSCADSharp/OSCADObject.cs
index 3a41ad7..3e8b537 100644
--- a/OSCADSharp/OSCADSharp/OSCADObject.cs
+++ b/OSCADSharp/OSCADSharp/OSCADObject.cs
@@ -262,6 +262,11 @@ namespace OSCADSharp
             return this.ToString() == other.ToString();
         }
 
+        /// <summary>
+        /// The parent of this object in its OSCADObject tree
+        /// </summary>
+        internal OSCADObject Parent { get; set; }
+
         /// <summary>
         /// Internal collection of children for this object
         /// </summary>
@@ -323,8 +328,13 @@ namespace OSCADSharp
             {
                 path += ".scad";
             }
-
-            File.WriteAllLines(path, new string[] { this.ToString() });
+            
+            Settings.FileWriter.WriteAllLines(path, new string[] 
+            {
+                Settings.OSCADSharpHeader,
+                Settings.Globals.ToString(),
+                this.ToString()
+            });
         }
         #endregion
 
diff --git a/OSCADSharp/OSCADSharp/OSCADSharp.csproj b/OSCADSharp/OSCADSharp/OSCADSharp.csproj
index 23a88dd..1b7c5b0 100644
--- a/OSCADSharp/OSCADSharp/OSCADSharp.csproj
+++ b/OSCADSharp/OSCADSharp/OSCADSharp.csproj
@@ -42,7 +42,11 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="Scripting\DefaultFileWriter.cs" />
+    <Compile Include="Scripting\IFileWriter.cs" />
     <Compile Include="Ids.cs" />
+    <Compile Include="Scripting\StatementBuilder.cs" />
+    <Compile Include="Settings.cs" />
     <Compile Include="Sizes.cs" />
     <Compile Include="Spatial\Bounds.cs" />
     <Compile Include="Spatial\Matrix.cs" />
@@ -67,6 +71,7 @@
     <Compile Include="Transforms\ScaledObject.cs" />
     <Compile Include="Transforms\TranslatedObject.cs" />
     <Compile Include="Spatial\Vector3.cs" />
+    <Compile Include="Scripting\Variables.cs" />
   </ItemGroup>
   <ItemGroup />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
diff --git a/OSCADSharp/OSCADSharp/Scripting/DefaultFileWriter.cs b/OSCADSharp/OSCADSharp/Scripting/DefaultFileWriter.cs
new file mode 100644
index 0000000..05ae2e4
--- /dev/null
+++ b/OSCADSharp/OSCADSharp/Scripting/DefaultFileWriter.cs
@@ -0,0 +1,17 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace OSCADSharp.Scripting
+{
+    internal class DefaultFileWriter : IFileWriter
+    {
+        public void WriteAllLines(string path, string[] contents)
+        {
+            File.WriteAllLines(path, contents);
+        }
+    }
+}
diff --git a/OSCADSharp/OSCADSharp/Scripting/IFileWriter.cs b/OSCADSharp/OSCADSharp/Scripting/IFileWriter.cs
new file mode 100644
index 0000000..afdbb46
--- /dev/null
+++ b/OSCADSharp/OSCADSharp/Scripting/IFileWriter.cs
@@ -0,0 +1,21 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace OSCADSharp.Scripting
+{
+    /// <summary>
+    /// A class that takes text and writes to file
+    /// </summary>
+    public interface IFileWriter
+    {
+        /// <summary>
+        /// Writes lines of text to a file at the path specified
+        /// </summary>
+        /// <param name="path"></param>
+        /// <param name="contents"></param>
+        void WriteAllLines(string path, string[] contents);
+    }
+}
diff --git a/OSCADSharp/OSCADSharp/Scripting/MultiBlockStatementObject.cs b/OSCADSharp/OSCADSharp/Scripting/MultiBlockStatementObject.cs
index f1a8c7c..8faa9d7 100644
--- a/OSCADSharp/OSCADSharp/Scripting/MultiBlockStatementObject.cs
+++ b/OSCADSharp/OSCADSharp/Scripting/MultiBlockStatementObject.cs
@@ -20,6 +20,10 @@ namespace OSCADSharp.Scripting
         {
             this.outerStatement = outerStatement;
             this.children = children.ToList();
+            foreach (var child in children)
+            {
+                child.Parent = this;
+            }
         }
 
         public override string ToString()
diff --git a/OSCADSharp/OSCADSharp/Scripting/StatementBuilder.cs b/OSCADSharp/OSCADSharp/Scripting/StatementBuilder.cs
new file mode 100644
index 0000000..30171ad
--- /dev/null
+++ b/OSCADSharp/OSCADSharp/Scripting/StatementBuilder.cs
@@ -0,0 +1,64 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace OSCADSharp.Scripting
+{
+    /// <summary>
+    /// Extends the capabilities of StringBuilder with domain-specific behavior
+    /// </summary>
+    internal class StatementBuilder
+    {
+        private StringBuilder SB { get; set; } = new StringBuilder();
+
+        /// <summary>
+        /// Special append method for conditionally adding value-pairs
+        /// </summary>
+        /// <param name="name">The Name of the value-pair</param>
+        /// <param name="value">The value - if null this method does nothing</param>
+        /// <param name="prefixWithComma">(optional) Flag indicating whether a comma should be added before the value-pair</param>
+        public void AppendValuePairIfExists(string name, object value, bool prefixWithComma = false)
+        {
+            if (!String.IsNullOrEmpty(value?.ToString()))
+            {
+                if (prefixWithComma)
+                {
+                    SB.Append(", ");
+                }
+
+                SB.Append(name);
+                SB.Append(" = ");
+                SB.Append(value);
+            }
+        }
+
+        /// <summary>
+        /// Pass-through for StringBuilder.Append
+        /// </summary>
+        /// <param name="text"></param>
+        public void Append(string text)
+        {
+            SB.Append(text);
+        }
+
+        /// <summary>
+        /// Pass-through for StringBuilder.AppendLine
+        /// </summary>
+        /// <param name="text"></param>
+        public void AppendLine(string text)
+        {
+            SB.AppendLine(text);
+        }
+
+        /// <summary>
+        /// Gets this builder's full string
+        /// </summary>
+        /// <returns></returns>
+        public override string ToString()
+        {
+            return SB.ToString();
+        }
+    }
+}
diff --git a/OSCADSharp/OSCADSharp/Scripting/Variables.cs b/OSCADSharp/OSCADSharp/Scripting/Variables.cs
new file mode 100644
index 0000000..1a47561
--- /dev/null
+++ b/OSCADSharp/OSCADSharp/Scripting/Variables.cs
@@ -0,0 +1,67 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace OSCADSharp.Scripting
+{
+    /// <summary>
+    /// A collection of names/values for variables
+    /// </summary>
+    public sealed class Variables
+    {
+        private Dictionary<string, object> variables = new Dictionary<string, object>();
+
+        /// <summary>
+        /// Assigns or gets a variable's value
+        /// </summary>
+        /// <param name="name"></param>
+        /// <returns></returns>
+        public object this[string name]   // long is a 64-bit integer
+        {
+            get
+            {
+                if (variables.ContainsKey(name))
+                {
+                    return variables[name];
+                }
+                else
+                {
+                    return null;
+                }
+            }
+            set
+            {
+                variables[name] = value;
+            }
+        }
+
+        /// <summary>
+        /// This class is intended for use in other externally-exposed classes,
+        /// as such its constructor is not public.
+        /// </summary>
+        internal Variables()
+        {
+        }
+
+        /// <summary>
+        /// Gets the string representation for all variables
+        /// </summary>
+        /// <returns></returns>
+        public override string ToString()
+        {
+            StringBuilder sb = new StringBuilder();
+            foreach (var kvp in this.variables)
+            {
+                sb.Append(kvp.Key);
+                sb.Append(" = ");
+                sb.Append(kvp.Value);
+                sb.Append(";");
+                sb.Append(Environment.NewLine);
+            }
+
+            return sb.ToString();
+        }
+    }
+}
diff --git a/OSCADSharp/OSCADSharp/Settings.cs b/OSCADSharp/OSCADSharp/Settings.cs
new file mode 100644
index 0000000..d6b183f
--- /dev/null
+++ b/OSCADSharp/OSCADSharp/Settings.cs
@@ -0,0 +1,32 @@
+using OSCADSharp.Scripting;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace OSCADSharp
+{
+    /// <summary>
+    /// Settings for OpenSCAD scripts
+    /// </summary>
+    public static class Settings
+    {
+        /// <summary>
+        /// Code-gen header
+        /// </summary>
+        public static readonly string OSCADSharpHeader = String.Format("/*Code Generated using OSCADSharp on {0}. {1}{2}For more information, please visit https://github.com/Exolun/OSCADSharp */{3}", 
+            DateTime.Now.ToString(), Environment.NewLine, Environment.NewLine, Environment.NewLine);
+
+        /// <summary>
+        /// Global variables that can be assigned for output at the 
+        /// top of OpenSCAD scripts
+        /// </summary>
+        public static Variables Globals = new Variables();
+
+        /// <summary>
+        /// Used to write scripts to file
+        /// </summary>
+        public static IFileWriter FileWriter = new DefaultFileWriter();
+    }
+}
diff --git a/OSCADSharp/OSCADSharp/Solids/Cylinder.cs b/OSCADSharp/OSCADSharp/Solids/Cylinder.cs
index 5fe08b8..a70fc47 100644
--- a/OSCADSharp/OSCADSharp/Solids/Cylinder.cs
+++ b/OSCADSharp/OSCADSharp/Solids/Cylinder.cs
@@ -4,6 +4,7 @@ using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
 using OSCADSharp.Spatial;
+using OSCADSharp.Scripting;
 
 namespace OSCADSharp.Solids
 {
@@ -81,19 +82,19 @@ namespace OSCADSharp.Solids
         /// Minimum angle (in degrees) of each cylinder fragment.
         /// ($fa in OpenSCAD)
         /// </summary>
-        public int MinimumAngle { get; set; } = 12;
+        public int? MinimumAngle { get; set; }
 
         /// <summary>
         /// Minimum circumferential length of each fragment.
         /// ($fs in OpenSCAD)
         /// </summary>
-        public int MinimumCircumferentialLength { get; set; } = 2;
+        public int? MinimumCircumferentialLength { get; set; }
 
         /// <summary>
         /// Number of fragments in 360 degrees. Values of 3 or more override MinimumAngle and MinimumCircumferentialLength
         /// ($fn in OpenSCAD)
         /// </summary>
-        public int Resolution { get; set; } = 0;
+        public int? Resolution { get; set; }
         #endregion
 
         #region Constructors
@@ -125,9 +126,18 @@ namespace OSCADSharp.Solids
         /// <returns>Script for this object</returns>
         public override string ToString()
         {
-            return String.Format("cylinder($fn = {0}, $fa = {1}, $fs = {2}, h = {3}, r1 = {4}, r2 = {5}, center = {6}); {7}", 
-                Resolution.ToString(), MinimumAngle.ToString(),  MinimumCircumferentialLength.ToString(),
-                Height.ToString(), Radius1.ToString(), Radius2.ToString(), Center.ToString().ToLower(), Environment.NewLine);
+            var sb = new StatementBuilder();
+            sb.Append("cylinder(");
+            sb.AppendValuePairIfExists("center", this.Center.ToString().ToLower());
+            sb.AppendValuePairIfExists("r1", this.Radius1, true);
+            sb.AppendValuePairIfExists("r2", this.Radius2, true);
+            sb.AppendValuePairIfExists("h", this.Height, true);
+            sb.AppendValuePairIfExists("$fn", this.Resolution, true);
+            sb.AppendValuePairIfExists("$fa", this.MinimumAngle, true);
+            sb.AppendValuePairIfExists("$fs", this.MinimumCircumferentialLength, true);
+            sb.Append(");");
+            sb.Append(Environment.NewLine);
+            return sb.ToString();
         }
 
         /// <summary>
diff --git a/OSCADSharp/OSCADSharp/Solids/Sphere.cs b/OSCADSharp/OSCADSharp/Solids/Sphere.cs
index 766decb..20d2d56 100644
--- a/OSCADSharp/OSCADSharp/Solids/Sphere.cs
+++ b/OSCADSharp/OSCADSharp/Solids/Sphere.cs
@@ -4,6 +4,7 @@ using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
 using OSCADSharp.Spatial;
+using OSCADSharp.Scripting;
 
 namespace OSCADSharp.Solids
 {
@@ -30,19 +31,19 @@ namespace OSCADSharp.Solids
         /// Minimum angle (in degrees) of each cylinder fragment.
         /// ($fa in OpenSCAD)
         /// </summary>
-        public int MinimumAngle { get; set; } = 12;
+        public int? MinimumAngle { get; set; }
 
         /// <summary>
         /// Fragment size in mm
         /// ($fs in OpenSCAD)
         /// </summary>
-        public int MinimumFragmentSize { get; set; } = 2;
+        public int? MinimumFragmentSize { get; set; }
 
         /// <summary>
         /// Number of fragments in 360 degrees. Values of 3 or more override MinimumAngle and MinimumCircumferentialLength
         /// ($fn in OpenSCAD)
         /// </summary>
-        public int Resolution { get; set; } = 0;
+        public int? Resolution { get; set; }
         #endregion
 
         #region Constructors
@@ -70,9 +71,16 @@ namespace OSCADSharp.Solids
         /// <returns>Script for this object</returns>
         public override string ToString()
         {
-            return String.Format("sphere($fn = {0}, $fa = {1}, $fs = {2}, r = {3});{4}", 
-                this.Resolution.ToString(), this.MinimumAngle.ToString(), 
-                this.MinimumFragmentSize.ToString(), this.Radius.ToString(), Environment.NewLine);
+            StatementBuilder sb = new StatementBuilder();
+            sb.Append("sphere(");
+            sb.AppendValuePairIfExists("r", this.Radius);
+            sb.AppendValuePairIfExists("$fn", this.Resolution, true);
+            sb.AppendValuePairIfExists("$fa", this.MinimumAngle, true);
+            sb.AppendValuePairIfExists("$fs", this.MinimumFragmentSize, true);
+            sb.Append(");");
+            sb.Append(Environment.NewLine);
+
+            return sb.ToString();
         }
 
         /// <summary>
diff --git a/OSCADSharp/OSCADSharp/Solids/Text3D.cs b/OSCADSharp/OSCADSharp/Solids/Text3D.cs
index 888da34..40045cd 100644
--- a/OSCADSharp/OSCADSharp/Solids/Text3D.cs
+++ b/OSCADSharp/OSCADSharp/Solids/Text3D.cs
@@ -107,22 +107,22 @@ namespace OSCADSharp.Solids
         /// <returns>Script for this object</returns>
         public override string ToString()
         {
-            StringBuilder sb = new StringBuilder();
+            StatementBuilder sb = new StatementBuilder();
             sb.Append("text(");
             sb.Append("\"");
             sb.Append(this.Text);
             sb.Append("\"");
 
-            appendIfValueNotNullOrEmpty("size", this.Size?.ToString(), sb);
+            sb.AppendValuePairIfExists("size", this.Size?.ToString(), true);
             // Text is always centered in OSCADSharp to ensure correctness of
             // position interpolation
-            appendIfValueNotNullOrEmpty("halign", "\"center\"", sb);
-            appendIfValueNotNullOrEmpty("valign", "\"center\"", sb);
+            sb.AppendValuePairIfExists("halign", "\"center\"", true);
+            sb.AppendValuePairIfExists("valign", "\"center\"", true);
 
-            appendIfValueNotNullOrEmpty("font", this.Font, sb);
-            appendIfValueNotNullOrEmpty("spacing", this.Spacing?.ToString(), sb);
-            appendIfValueNotNullOrEmpty("direction", this.TextDirection?.ToString(), sb);
-            appendIfValueNotNullOrEmpty("language", this.Language?.ToString(), sb);            
+            sb.AppendValuePairIfExists("font", this.Font, true);
+            sb.AppendValuePairIfExists("spacing", this.Spacing?.ToString(), true);
+            sb.AppendValuePairIfExists("direction", this.TextDirection?.ToString(), true);
+            sb.AppendValuePairIfExists("language", this.Language?.ToString(), true);            
 
             sb.Append(");");
             sb.Append(Environment.NewLine);
@@ -145,6 +145,7 @@ namespace OSCADSharp.Solids
 
         /// <summary>
         /// Returns the approximate boundaries of this OpenSCAD object
+        /// </summary>
         /// <returns></returns>
         public override Bounds Bounds()
         {
diff --git a/OSCADSharp/OSCADSharp/Transforms/ColoredObject.cs b/OSCADSharp/OSCADSharp/Transforms/ColoredObject.cs
index 1d57142..9f02c14 100644
--- a/OSCADSharp/OSCADSharp/Transforms/ColoredObject.cs
+++ b/OSCADSharp/OSCADSharp/Transforms/ColoredObject.cs
@@ -33,6 +33,7 @@ namespace OSCADSharp.Transforms
             this.Opacity = opacity;
 
             this.children.Add(obj);
+            obj.Parent = this;
         }
 
         public override string ToString()
diff --git a/OSCADSharp/OSCADSharp/Transforms/LinearExtrudedObject.cs b/OSCADSharp/OSCADSharp/Transforms/LinearExtrudedObject.cs
index 0467bb6..0f6900c 100644
--- a/OSCADSharp/OSCADSharp/Transforms/LinearExtrudedObject.cs
+++ b/OSCADSharp/OSCADSharp/Transforms/LinearExtrudedObject.cs
@@ -35,6 +35,7 @@ namespace OSCADSharp.Transforms
             this.Height = height;
 
             this.children.Add(obj);
+            obj.Parent = this;
         }
 
         public override OSCADObject Clone()
diff --git a/OSCADSharp/OSCADSharp/Transforms/MirroredObject.cs b/OSCADSharp/OSCADSharp/Transforms/MirroredObject.cs
index 68796d2..7cad6ca 100644
--- a/OSCADSharp/OSCADSharp/Transforms/MirroredObject.cs
+++ b/OSCADSharp/OSCADSharp/Transforms/MirroredObject.cs
@@ -32,6 +32,7 @@ namespace OSCADSharp.Transforms
             this.Normal = normal;
 
             this.children.Add(obj);
+            obj.Parent = this;
         }
         
         public override string ToString()
diff --git a/OSCADSharp/OSCADSharp/Transforms/ResizedObject.cs b/OSCADSharp/OSCADSharp/Transforms/ResizedObject.cs
index 6cb5b03..f8eff1a 100644
--- a/OSCADSharp/OSCADSharp/Transforms/ResizedObject.cs
+++ b/OSCADSharp/OSCADSharp/Transforms/ResizedObject.cs
@@ -30,6 +30,7 @@ namespace OSCADSharp.Transforms
             this.Size = size;
 
             this.children.Add(obj);
+            obj.Parent = this;
         }
 
         public override string ToString()
diff --git a/OSCADSharp/OSCADSharp/Transforms/RotatedObject.cs b/OSCADSharp/OSCADSharp/Transforms/RotatedObject.cs
index 460123d..616b78f 100644
--- a/OSCADSharp/OSCADSharp/Transforms/RotatedObject.cs
+++ b/OSCADSharp/OSCADSharp/Transforms/RotatedObject.cs
@@ -30,6 +30,7 @@ namespace OSCADSharp.Transforms
             this.Angle = angle;
 
             this.children.Add(obj);
+            obj.Parent = this;
         }
 
         public override string ToString()
diff --git a/OSCADSharp/OSCADSharp/Transforms/ScaledObject.cs b/OSCADSharp/OSCADSharp/Transforms/ScaledObject.cs
index 5bcee35..e4d230e 100644
--- a/OSCADSharp/OSCADSharp/Transforms/ScaledObject.cs
+++ b/OSCADSharp/OSCADSharp/Transforms/ScaledObject.cs
@@ -30,6 +30,7 @@ namespace OSCADSharp.Transforms
             this.ScaleFactor = scale;
 
             this.children.Add(obj);
+            obj.Parent = this;
         }
 
         public override string ToString()
diff --git a/OSCADSharp/OSCADSharp/Transforms/TranslatedObject.cs b/OSCADSharp/OSCADSharp/Transforms/TranslatedObject.cs
index a1cd635..b8445f3 100644
--- a/OSCADSharp/OSCADSharp/Transforms/TranslatedObject.cs
+++ b/OSCADSharp/OSCADSharp/Transforms/TranslatedObject.cs
@@ -27,6 +27,7 @@ namespace OSCADSharp.Transforms
             this.Vector = vector;
 
             this.children.Add(obj);
+            obj.Parent = this;            
         }
 
         public override string ToString()