diff --git a/Pocketing.cpp b/Pocketing.cpp
index dc159b7..2bc1283 100644
--- a/Pocketing.cpp
+++ b/Pocketing.cpp
@@ -4683,12 +4683,12 @@ Pocketing::GetMidOfLongestOpenSide( const ICurveComposite* pCompo, Point3d& ptMi
             if ( pPrevCrv != nullptr  &&  pPrevCrv->GetTempProp() == 1) {
                Vector3d vtPrevEnd ;  pPrevCrv->GetEndDir( vtPrevEnd) ;
                Vector3d vtStart ;  pCrv->GetStartDir( vtStart) ;
-               dLenAgg += max( 0., vtPrevEnd * vtStart * dLenPrev) ;
+               dLenAgg += max( 0.25, vtPrevEnd * vtStart) * dLenPrev ;
             }
             if ( pNextCrv != nullptr  &&  pNextCrv->GetTempProp() == 1) {
                Vector3d vtEnd ;  pCrv->GetEndDir( vtEnd) ;
                Vector3d vtNextStart ;  pNextCrv->GetStartDir( vtNextStart) ;
-               dLenAgg += max( 0., vtEnd * vtNextStart * dLenNext) ;
+               dLenAgg += max( 0.25, vtEnd * vtNextStart) * dLenNext ;
             }
          }
         // entità corrente