diff --git a/src/body.cpp b/src/body.cpp
index 5af100f024..21f16e46c8 100644
--- a/src/body.cpp
+++ b/src/body.cpp
@@ -1507,13 +1507,17 @@ DynamicBody::saveToXml(QTextStream &xml) {
 void
 DynamicBody::setCoG(const position &newCoG)
 {
-  CoG = newCoG;
+  CoG = newCoG;  
   resetDynamics();
-  //use this to display axes at the CoG
-  //axesTranToCOG->translation.setValue(CoG.x(), CoG.y(), CoG.z());
 
-  //use this to display axes at body origin
-  axesTranToCOG->translation.setValue(0, 0, 0);
+  if (graspitCore && axesTranToCOG)
+  {
+    //use this to display axes at the CoG
+    //axesTranToCOG->translation.setValue(CoG.x(), CoG.y(), CoG.z());
+
+    //use this to display axes at body origin
+    axesTranToCOG->translation.setValue(0, 0, 0);
+  }
 }
 
 /*! The max radius can be thought of as the largest distance from the center
@@ -1523,7 +1527,10 @@ void
 DynamicBody::setMaxRadius(double maxRad)
 {
   maxRadius = maxRad;
-  axesScale->scaleFactor = SbVec3f(maxRadius / AXES_SCALE, maxRadius / AXES_SCALE, maxRadius / AXES_SCALE);
+  if (graspitCore && axesScale)
+  {
+    axesScale->scaleFactor = SbVec3f(maxRadius / AXES_SCALE, maxRadius / AXES_SCALE, maxRadius / AXES_SCALE);
+  }
 }
 
 void