diff --git a/OdeWorld.cc b/OdeWorld.cc
index 0e62880..f567618 100644
--- a/OdeWorld.cc
+++ b/OdeWorld.cc
@@ -116,6 +116,7 @@ OdeWorld::Object::Object(bool is_static, dWorldID world, dSpaceID space)
     m_world = world;
     m_space = space;
     m_body = 0;
+    dMassSetZero(&m_mass);
 }
 
 OdeWorld::Object::Object(const OdeWorld::Object & orig)
@@ -127,9 +128,8 @@ OdeWorld::Object::Object(const OdeWorld::Object & orig)
     if (orig.m_body != 0)
     {
         m_body = dBodyCreate(m_world);
-        dMass mass;
-        dBodyGetMass(orig.m_body, &mass);
-        dBodySetMass(m_body, &mass);
+        m_mass = orig.m_mass;
+        dBodySetMass(m_body, &m_mass);
         const dReal * pos = dBodyGetPosition(orig.m_body);
         dBodySetPosition(m_body, pos[0], pos[1], pos[2]);
         const dReal * rot = dBodyGetRotation(orig.m_body);
@@ -340,6 +340,11 @@ void OdeWorld::Object::loadPhy(const std::string & path)
             }
         }
     }
+    if (m_body != 0)
+    {
+        dMassTranslate(&m_mass, -m_mass.c[0], -m_mass.c[1], -m_mass.c[2]);
+        dBodySetMass(m_body, &m_mass);
+    }
 }
 
 void OdeWorld::Object::addCube(const vector<float> args)
@@ -436,10 +441,7 @@ void OdeWorld::Object::setupGeom(dGeomID geom, dMass * mass,
 
         dMassRotate(mass, rot);
         dMassTranslate(mass, locx, locy, locz);
-        dMass origmass;
-        dBodyGetMass(m_body, &origmass);
-        dMassAdd(&origmass, mass);
-        dBodySetMass(m_body, &origmass);
+        dMassAdd(&m_mass, mass);
     }
 }
 
diff --git a/OdeWorld.h b/OdeWorld.h
index 43b3f7a..0c10d59 100644
--- a/OdeWorld.h
+++ b/OdeWorld.h
@@ -35,6 +35,7 @@ class OdeWorld
             protected:
                 bool    m_is_static;
                 dBodyID m_body;
+                dMass   m_mass;
                 dWorldID m_world;
                 dSpaceID m_space;
                 std::vector<dGeomID> m_geoms;