diff --git a/src/Mod/Part/App/GeometryDefaultExtension.cpp b/src/Mod/Part/App/GeometryDefaultExtension.cpp
index 6adbb62bec..426df6de85 100644
--- a/src/Mod/Part/App/GeometryDefaultExtension.cpp
+++ b/src/Mod/Part/App/GeometryDefaultExtension.cpp
@@ -37,7 +37,7 @@ using namespace Part;
 
 //---------- Geometry Extension
 template <typename T>
-GeometryDefaultExtension<T>::GeometryDefaultExtension(const T& obj):value(obj)
+GeometryDefaultExtension<T>::GeometryDefaultExtension(const T& val):value(val)
 {
 
 }
diff --git a/src/Mod/Part/App/GeometryDefaultExtension.h b/src/Mod/Part/App/GeometryDefaultExtension.h
index 89f567143b..2276035808 100644
--- a/src/Mod/Part/App/GeometryDefaultExtension.h
+++ b/src/Mod/Part/App/GeometryDefaultExtension.h
@@ -35,9 +35,12 @@ namespace Part {
         TYPESYSTEM_HEADER();
     public:
         GeometryDefaultExtension() = default;
-        GeometryDefaultExtension(const T& obj);
+        GeometryDefaultExtension(const T& val);
         virtual ~GeometryDefaultExtension() = default;
 
+        inline void setValue(const T& val) {value = val;};
+        inline const T &getValue() {return value;};
+
         // Persistence implementer ---------------------
         virtual unsigned int getMemSize(void) const;
         virtual void Save(Base::Writer &/*writer*/) const;
@@ -47,7 +50,7 @@ namespace Part {
 
         virtual PyObject *getPyObject(void);
 
-    public:
+    private:
         T value;
     };
 
diff --git a/src/Mod/Part/App/GeometryIntExtensionPyImp.cpp b/src/Mod/Part/App/GeometryIntExtensionPyImp.cpp
index d2d8600219..5bb42f8d9e 100644
--- a/src/Mod/Part/App/GeometryIntExtensionPyImp.cpp
+++ b/src/Mod/Part/App/GeometryIntExtensionPyImp.cpp
@@ -34,7 +34,7 @@ using namespace Part;
 std::string GeometryIntExtensionPy::representation(void) const
 {
     std::stringstream str;
-    long id = getGeometryIntExtensionPtr()->value;
+    long id = getGeometryIntExtensionPtr()->getValue();
     str << "<GeometryIntExtension (" << id << ") >";
     return str.str();
 }
@@ -57,7 +57,7 @@ int GeometryIntExtensionPy::PyInit(PyObject* args, PyObject* /*kwd*/)
     PyErr_Clear();
     int Id;
     if (PyArg_ParseTuple(args, "i", &Id)) {
-        this->getGeometryIntExtensionPtr()->value=Id;
+        this->getGeometryIntExtensionPtr()->setValue(Id);
         return 0;
     }
 
@@ -71,12 +71,12 @@ int GeometryIntExtensionPy::PyInit(PyObject* args, PyObject* /*kwd*/)
 
 Py::Long GeometryIntExtensionPy::getValue(void) const
 {
-    return Py::Long(this->getGeometryIntExtensionPtr()->value);
+    return Py::Long(this->getGeometryIntExtensionPtr()->getValue());
 }
 
 void GeometryIntExtensionPy::setValue(Py::Long value)
 {
-    this->getGeometryIntExtensionPtr()->value=long(value);
+    this->getGeometryIntExtensionPtr()->setValue(long(value));
 }
 
 
diff --git a/src/Mod/Part/App/GeometryStringExtensionPyImp.cpp b/src/Mod/Part/App/GeometryStringExtensionPyImp.cpp
index f1b39a0f6b..3315c4641a 100644
--- a/src/Mod/Part/App/GeometryStringExtensionPyImp.cpp
+++ b/src/Mod/Part/App/GeometryStringExtensionPyImp.cpp
@@ -38,7 +38,7 @@ using namespace Part;
 std::string GeometryStringExtensionPy::representation(void) const
 {
     std::stringstream str;
-    str << "<GeometryStringExtension (" << getGeometryStringExtensionPtr()->value << ") >";
+    str << "<GeometryStringExtension (" << getGeometryStringExtensionPtr()->getValue() << ") >";
     return str.str();
 }
 
@@ -60,7 +60,7 @@ int GeometryStringExtensionPy::PyInit(PyObject* args, PyObject* /*kwd*/)
     PyErr_Clear();
     char *pstr;
     if (PyArg_ParseTuple(args, "s", &pstr)) {
-        this->getGeometryStringExtensionPtr()->value=pstr;
+        this->getGeometryStringExtensionPtr()->setValue(pstr);
         return 0;
     }
 
@@ -74,12 +74,12 @@ int GeometryStringExtensionPy::PyInit(PyObject* args, PyObject* /*kwd*/)
 
 Py::String GeometryStringExtensionPy::getValue(void) const
 {
-    return Py::String(this->getGeometryStringExtensionPtr()->value);
+    return Py::String(this->getGeometryStringExtensionPtr()->getValue());
 }
 
 void GeometryStringExtensionPy::setValue(Py::String value)
 {
-    this->getGeometryStringExtensionPtr()->value = value.as_std_string();
+    this->getGeometryStringExtensionPtr()->setValue(value.as_std_string());
 }
 
 PyObject *GeometryStringExtensionPy::getCustomAttributes(const char* /*attr*/) const