diff --git a/phy_export.py b/phy_export.py
index 7a68992..3edcb35 100644
--- a/phy_export.py
+++ b/phy_export.py
@@ -26,19 +26,23 @@ def write(filename):
                 e = ob.getEuler()
                 size = ob.getSize()
                 out.write("cube \"%s\" %f %f %f  %f %f %f  %f %f %f\n" %
-                        ((ob.name,2*size[0],2*size[1],2*size[2]) +
+                        ((ob.name,
+                            2 * abs(size[0]),
+                            2 * abs(size[1]),
+                            2 * abs(size[2])) +
                             ob.getLocation() +
                             (e[0], e[1], e[2])))
             elif len(ob.data.faces) < 256:
                 # found a capsule
                 e = ob.getEuler()
                 out.write("capsule \"%s\" %f %f  %f %f %f  %f %f %f\n" %
-                        ((ob.name,) + (ob.getSize()[0], ob.getSize()[2]*2) +
-                            ob.getLocation() +
-                            (e[0], e[1], e[2])))
+                        ((ob.name,)
+                            + (abs(ob.getSize()[0]), abs(ob.getSize()[2]) * 2)
+                            + ob.getLocation()
+                            + (e[0], e[1], e[2])))
             elif len(ob.data.faces) >= 256:
                 # found a sphere
                 out.write("sphere \"%s\" %f  %f %f %f\n" %
-                        ((ob.name, ob.SizeX) + ob.getLocation()))
+                        ((ob.name, abs(ob.SizeX)) + ob.getLocation()))
 
 Blender.Window.FileSelector(write, "Export")