diff --git a/ChainCurves.cpp b/ChainCurves.cpp
index 01eface..4eb37bc 100644
--- a/ChainCurves.cpp
+++ b/ChainCurves.cpp
@@ -284,8 +284,8 @@ ChainCurves::ChooseStart( const Point3d& ptStart, const INTVECTOR& vStart, int&
       double dSqDist = SqDist( ptStart, ptNear) ;
       // tengo il segmento più vicino al punto
       // favorendo eventualmente quello equiverso se entro EPS da un concorrente
-      if ( dSqDist < dSqDistMin - EPS_SMALL  ||
-         ((dSqDist < dSqDistMin + EPS_SMALL)  &&  bEquiv  &&  vStart[nI] < 0)) {
+      if ( dSqDist < dSqDistMin - 2 * EPS_SMALL  ||
+         ((dSqDist < dSqDistMin + 2 * EPS_SMALL)  &&  bEquiv  &&  vStart[nI] < 0)) {
          dSqDistMin = dSqDist ;
          nI = i ;
       }