diff --git a/vr-configurator/Assets/Scenes/SampleScene.unity b/vr-configurator/Assets/Scenes/SampleScene.unity
index 0dd73de..0e1ffce 100644
--- a/vr-configurator/Assets/Scenes/SampleScene.unity
+++ b/vr-configurator/Assets/Scenes/SampleScene.unity
@@ -12934,6 +12934,7 @@ MonoBehaviour:
   colliderSurface: {fileID: 163506087}
   interactable: {fileID: 698127119}
   rayInteractable: {fileID: 698127110}
+  afterBirth: 0
   PortSelector: {fileID: 1494770816}
   Index: -1
 --- !u!1 &700047848
@@ -21960,6 +21961,7 @@ MonoBehaviour:
   colliderSurface: {fileID: 557957011}
   interactable: {fileID: 1272917968}
   rayInteractable: {fileID: 1272917969}
+  afterBirth: 0
   PortSelector: {fileID: 1494770816}
   Index: -1
 --- !u!114 &1272917968
diff --git a/vr-configurator/Assets/Scripts/Models/ModelBehaviour.cs b/vr-configurator/Assets/Scripts/Models/ModelBehaviour.cs
index e387aa0..45f3774 100644
--- a/vr-configurator/Assets/Scripts/Models/ModelBehaviour.cs
+++ b/vr-configurator/Assets/Scripts/Models/ModelBehaviour.cs
@@ -34,6 +34,8 @@ public class ModelBehaviour : MonoBehaviour, IResettable
 
     bool lateInited = false;
 
+    public bool afterBirth = false;
+
     public PortSelector PortSelector;
     public int Index = -1;
 
@@ -133,6 +135,8 @@ public class ModelBehaviour : MonoBehaviour, IResettable
             Debug.Log($"Spawning {gameObject.name}'s ports");
             SpawnChildPorts(newModel);
         }
+
+        afterBirth = true;
     }
 
     void LateUpdateModel()
diff --git a/vr-configurator/Assets/Scripts/Transform/Exploder.cs b/vr-configurator/Assets/Scripts/Transform/Exploder.cs
index ea23bb5..f647724 100644
--- a/vr-configurator/Assets/Scripts/Transform/Exploder.cs
+++ b/vr-configurator/Assets/Scripts/Transform/Exploder.cs
@@ -62,47 +62,41 @@ public class Exploder : MonoBehaviour, IResettable, IPointerDownHandler
 
     void PopulateModelList()
     {
-        models.Clear();
+        List<ExploderModel> newModels = new List<ExploderModel>();
         foreach (Transform child in baseModel.GetComponentsInChildren<Transform>())
         {
             var cmb = child.GetComponent<ChildModelBehaviour>();
             if (cmb == null)
             {
-                continue; //only for basemodel
+                continue; //skip basemodel
             }
-            Port port = cmb.GetParentPort();
-            models.Add(new ExploderModel(port, cmb.ChildModel, cmb));
-        }
-    }
-
-    void UpdateModelList()
-    {
-        List<ExploderModel> modelss = new List<ExploderModel>();
-        foreach (var exploModel in models)
-        {
-            if (exploModel.cmb == null)
+            bool skip = false;
+            foreach (var model in models)
             {
-                continue; //skip dead ends
-            }
-            if (exploModel.model != exploModel.cmb.ChildModel) //update
-            {
-                Debug.LogWarning($"Updating Model List from {exploModel.model.NameId} to {exploModel.cmb.ChildModel.NameId}");
-                // add children + itself
-                foreach (Transform child in exploModel.cmb.GetComponentsInChildren<Transform>())
+                if (model.tf == child) 
                 {
-                    var cmb = child.GetComponent<ChildModelBehaviour>();
-                    if (cmb == null)
+                    if (model.model == cmb.ChildModel) //nothing changed
                     {
-                        continue;
+                        newModels.Add(model);
                     }
-                    Port port = cmb.GetParentPort();
-                    modelss.Add(new ExploderModel(port, cmb.ChildModel, cmb));
+                    else // model is changed -> its unexploded
+                    {
+                        newModels.Add(new ExploderModel(model.port, cmb.ChildModel, model.cmb, model.tf, false));
+                    }
+                    skip = true;
+                    break;
                 }
+            }
+            if (skip)
+            {
                 continue;
             }
-            modelss.Add(exploModel);
+            //new model altogether -> its unexploded
+            Port port = cmb.GetParentPort();
+            newModels.Add(new ExploderModel(port, cmb.ChildModel, cmb, child, false));
         }
-        models = modelss;
+        models.Clear();
+        models = newModels;
     }
 
     void CleanModelList()
@@ -112,6 +106,7 @@ public class Exploder : MonoBehaviour, IResettable, IPointerDownHandler
 
     void ForceSetPos()
     {
+        Debug.Log($"ForceSetPos {explode}");
         foreach (var exploModel in models)
         {
             exploModel.tf.localPosition = explode ? exploModel.goalPos : exploModel.initPos;
@@ -135,8 +130,12 @@ public class Exploder : MonoBehaviour, IResettable, IPointerDownHandler
 
     public void HandleModelChange()
     {
-        UpdateModelList();
-        ForceSetPos();
+        //UpdateModelList();
+        if (mm.BaseModelBehaviour.afterBirth)
+        {
+            PopulateModelList();
+            ForceSetPos();
+        }
     }
 
     public void ResetThis()
diff --git a/vr-configurator/Assets/Scripts/Transform/ExploderModel.cs b/vr-configurator/Assets/Scripts/Transform/ExploderModel.cs
index 22cde73..80cd285 100644
--- a/vr-configurator/Assets/Scripts/Transform/ExploderModel.cs
+++ b/vr-configurator/Assets/Scripts/Transform/ExploderModel.cs
@@ -12,18 +12,18 @@ public class ExploderModel
     public Vector3 initPos;
     public Vector3 goalPos;
 
-    public ExploderModel(Port port, ChildModel model, ChildModelBehaviour cmb)
+    public ExploderModel(Port port, ChildModel model, ChildModelBehaviour cmb, Transform tf, bool exploded)
     {
         this.port = port;
         this.model = model;
         this.cmb = cmb;
-        CalculatePos();
+        this.tf = tf;
+        CalculatePos(exploded);
     }
 
-    public void CalculatePos()
+    public void CalculatePos(bool exploded = false)
     {
-        tf = cmb.transform;
-        initPos = tf.localPosition;
-        goalPos = tf.localPosition + port.ExplodeDirection;
+        initPos = exploded ? tf.localPosition - port.ExplodeDirection : tf.localPosition;
+        goalPos = exploded ? tf.localPosition : tf.localPosition + port.ExplodeDirection;
     }
 }