diff --git a/jme3-core/src/main/java/com/jme3/material/ShaderGenerationInfo.java b/jme3-core/src/main/java/com/jme3/material/ShaderGenerationInfo.java
index fd3ce155f..ab06cdf0b 100644
--- a/jme3-core/src/main/java/com/jme3/material/ShaderGenerationInfo.java
+++ b/jme3-core/src/main/java/com/jme3/material/ShaderGenerationInfo.java
@@ -189,30 +189,30 @@ public class ShaderGenerationInfo implements Savable, Cloneable {
     }
 
     @Override
-    protected Object clone() throws CloneNotSupportedException {
+    protected ShaderGenerationInfo clone() throws CloneNotSupportedException {
         ShaderGenerationInfo clone = (ShaderGenerationInfo) super.clone();
 
         for (ShaderNodeVariable attribute : attributes) {
-            clone.attributes.add((ShaderNodeVariable) attribute.clone());
+            clone.attributes.add(attribute.clone());
         }
 
         for (ShaderNodeVariable uniform : vertexUniforms) {
-            clone.vertexUniforms.add((ShaderNodeVariable) uniform.clone());
+            clone.vertexUniforms.add(uniform.clone());
         }
 
-        clone.vertexGlobal = (ShaderNodeVariable) vertexGlobal.clone();
+        clone.vertexGlobal = vertexGlobal.clone();
 
 
         for (ShaderNodeVariable varying : varyings) {
-            clone.varyings.add((ShaderNodeVariable) varying.clone());
+            clone.varyings.add(varying.clone());
         }
 
         for (ShaderNodeVariable uniform : fragmentUniforms) {
-            clone.fragmentUniforms.add((ShaderNodeVariable) uniform.clone());
+            clone.fragmentUniforms.add(uniform.clone());
         }
 
         for (ShaderNodeVariable globals : fragmentGlobals) {
-            clone.fragmentGlobals.add((ShaderNodeVariable) globals.clone());
+            clone.fragmentGlobals.add(globals.clone());
         }
 
         clone.unusedNodes.addAll(unusedNodes);
diff --git a/jme3-core/src/main/java/com/jme3/material/TechniqueDef.java b/jme3-core/src/main/java/com/jme3/material/TechniqueDef.java
index 83135cf0c..429522c59 100644
--- a/jme3-core/src/main/java/com/jme3/material/TechniqueDef.java
+++ b/jme3-core/src/main/java/com/jme3/material/TechniqueDef.java
@@ -778,7 +778,7 @@ public class TechniqueDef implements Savable, Cloneable {
     }
 
     @Override
-    public Object clone() throws CloneNotSupportedException {
+    public TechniqueDef clone() throws CloneNotSupportedException {
         //cannot use super.clone because of the final fields instance that would be shared by the clones.
         TechniqueDef clone = new TechniqueDef(name, sortId);
 
@@ -802,9 +802,9 @@ public class TechniqueDef implements Savable, Cloneable {
 
         if (shaderNodes != null) {
             for (ShaderNode shaderNode : shaderNodes) {
-                clone.shaderNodes.add((ShaderNode) shaderNode.clone());
+                clone.shaderNodes.add(shaderNode.clone());
             }
-            clone.shaderGenerationInfo = (ShaderGenerationInfo) shaderGenerationInfo.clone();
+            clone.shaderGenerationInfo = shaderGenerationInfo.clone();
         }
 
         if (renderState != null) {
diff --git a/jme3-core/src/main/java/com/jme3/shader/ShaderNode.java b/jme3-core/src/main/java/com/jme3/shader/ShaderNode.java
index 9f8156933..4f5779363 100644
--- a/jme3-core/src/main/java/com/jme3/shader/ShaderNode.java
+++ b/jme3-core/src/main/java/com/jme3/shader/ShaderNode.java
@@ -214,7 +214,7 @@ public class ShaderNode implements Savable, Cloneable {
     }
 
     @Override
-    public Object clone() throws CloneNotSupportedException {
+    public ShaderNode clone() throws CloneNotSupportedException {
         ShaderNode clone = (ShaderNode) super.clone();
 
         //No need to clone the definition.
diff --git a/jme3-core/src/main/java/com/jme3/shader/ShaderNodeVariable.java b/jme3-core/src/main/java/com/jme3/shader/ShaderNodeVariable.java
index 7d0d959e3..22811de6f 100644
--- a/jme3-core/src/main/java/com/jme3/shader/ShaderNodeVariable.java
+++ b/jme3-core/src/main/java/com/jme3/shader/ShaderNodeVariable.java
@@ -278,7 +278,7 @@ public class ShaderNodeVariable implements Savable, Cloneable {
     }
 
     @Override
-    public Object clone() throws CloneNotSupportedException {
-        return super.clone();
+    public ShaderNodeVariable clone() throws CloneNotSupportedException {
+        return (ShaderNodeVariable) super.clone();
     }
 }
diff --git a/jme3-core/src/main/java/com/jme3/shader/VariableMapping.java b/jme3-core/src/main/java/com/jme3/shader/VariableMapping.java
index 61ae612fd..4a88c5d9f 100644
--- a/jme3-core/src/main/java/com/jme3/shader/VariableMapping.java
+++ b/jme3-core/src/main/java/com/jme3/shader/VariableMapping.java
@@ -197,11 +197,11 @@ public class VariableMapping implements Savable, Cloneable {
     }
 
     @Override
-    protected Object clone() throws CloneNotSupportedException {
+    protected VariableMapping clone() throws CloneNotSupportedException {
         VariableMapping clone = (VariableMapping) super.clone();
 
-        clone.leftVariable = (ShaderNodeVariable) leftVariable.clone();
-        clone.rightVariable = (ShaderNodeVariable) rightVariable.clone();
+        clone.leftVariable = leftVariable.clone();
+        clone.rightVariable = rightVariable.clone();
 
         return clone;
     }
diff --git a/jme3-core/src/plugins/java/com/jme3/material/plugins/J3MLoader.java b/jme3-core/src/plugins/java/com/jme3/material/plugins/J3MLoader.java
index 0dfaafd3c..e725301bb 100644
--- a/jme3-core/src/plugins/java/com/jme3/material/plugins/J3MLoader.java
+++ b/jme3-core/src/plugins/java/com/jme3/material/plugins/J3MLoader.java
@@ -615,6 +615,7 @@ public class J3MLoader implements AssetLoader {
     private void readTechnique(Statement techStat) throws IOException{
         isUseNodes = false;
         String[] split = techStat.getLine().split(whitespacePattern);
+        Cloner cloner = new Cloner();
 
         String name;
         if (split.length == 1) {
@@ -669,12 +670,8 @@ public class J3MLoader implements AssetLoader {
         }else if (shaderNames.containsKey(Shader.ShaderType.Vertex) && shaderNames.containsKey(Shader.ShaderType.Fragment)) {
             if (shaderLanguages.size() > 1) {
                 for (int i = 1; i < shaderLanguages.size(); i++) {
-                    TechniqueDef td = null;
-                    try {
-                        td = (TechniqueDef) technique.clone();
-                    } catch (CloneNotSupportedException e) {
-                        e.printStackTrace();
-                    }
+                    cloner.clearIndex();
+                    TechniqueDef td = cloner.clone(technique);
                     td.setShaderFile(shaderNames, shaderLanguages.get(i));
                     techniqueDefs.add(td);
                 }