diff --git a/src/ifcgeom/IfcGeomHelpers.cpp b/src/ifcgeom/IfcGeomHelpers.cpp
index dcfdfa7b98..4b187c409e 100644
--- a/src/ifcgeom/IfcGeomHelpers.cpp
+++ b/src/ifcgeom/IfcGeomHelpers.cpp
@@ -137,11 +137,10 @@ bool IfcGeom::convert(const Ifc2x3::IfcCartesianTransformationOperator3D::ptr l,
 	IfcGeom::convert(l->LocalOrigin(),origin);
 	gp_Dir axis1 (1.,0.,0.);
 	gp_Dir axis2 (0.,1.,0.);
-	gp_Dir axis3;
+	gp_Dir axis3 (0.,0.,1.);
 	if ( l->hasAxis1() ) IfcGeom::convert(l->Axis1(),axis1);
 	if ( l->hasAxis2() ) IfcGeom::convert(l->Axis2(),axis2);
 	if ( l->hasAxis3() ) IfcGeom::convert(l->Axis3(),axis3);
-	else axis3 = axis1.Crossed(axis2);
 	gp_Ax3 ax3 (origin,axis3,axis1);
 	if ( axis2.Dot(ax3.YDirection()) < 0 ) ax3.YReverse();
 	trsf.SetTransformation(ax3);
@@ -170,11 +169,10 @@ bool IfcGeom::convert(const Ifc2x3::IfcCartesianTransformationOperator3DnonUnifo
 	IfcGeom::convert(l->LocalOrigin(),origin);
 	gp_Dir axis1 (1.,0.,0.);
 	gp_Dir axis2 (0.,1.,0.);
-	gp_Dir axis3;
+	gp_Dir axis3 (0.,0.,1.);
 	if ( l->hasAxis1() ) IfcGeom::convert(l->Axis1(),axis1);
 	if ( l->hasAxis2() ) IfcGeom::convert(l->Axis2(),axis2);
 	if ( l->hasAxis3() ) IfcGeom::convert(l->Axis3(),axis3);
-	else axis3 = axis1.Crossed(axis2);
 	gp_Ax3 ax3 (origin,axis3,axis1);
 	if ( axis2.Dot(ax3.YDirection()) < 0 ) ax3.YReverse();
 	trsf.SetTransformation(ax3);