diff --git a/API_GdbCreateSurf.cpp b/API_GdbCreateSurf.cpp
index a144b07..06d069a 100644
--- a/API_GdbCreateSurf.cpp
+++ b/API_GdbCreateSurf.cpp
@@ -136,7 +136,7 @@ __stdcall EgtCreateSurfTriMeshByScrewing( int nParentId, int nCrvId,
    double dStepRotDeg = sqrt( 8 * dLinTol / dMaxRad) * RADTODEG ;
   // se superficie rototraslata, necessari limiti sulla lunghezza dei segmenti
    if ( fabs( dAngRotDeg) > EPS_ANG_SMALL  &&  fabs( dMove) > EPS_SMALL){
-      double dLenMax = 2 * fabs( dMove) * dStepRotDeg / dAngRotDeg ;
+      double dLenMax = 2 * fabs( dMove * dStepRotDeg / dAngRotDeg) ;
       bOk = bOk && PL.AdjustForMaxSegmentLen( dLenMax) ;
    }
   // creo e setto la superficie trimesh
diff --git a/EgtInterface.rc b/EgtInterface.rc
index 0706552..9ef49d6 100644
Binary files a/EgtInterface.rc and b/EgtInterface.rc differ