diff --git a/Detector/DetSegmentation/DetSegmentation/GridDriftChamber.h b/Detector/DetSegmentation/DetSegmentation/GridDriftChamber.h
index ef39f69260ca98bfdf1c3e08335a8058f2a812cf..465388fef4aaa563dae9e45b1e0b5b646cbbb160 100644
--- a/Detector/DetSegmentation/DetSegmentation/GridDriftChamber.h
+++ b/Detector/DetSegmentation/DetSegmentation/GridDriftChamber.h
@@ -23,7 +23,7 @@ typedef struct Layer
    double eps;
    double offset;
    Layer(){};
-   Layer(double x, double y, double z, double k):layerphi(x),R(y),eps(z),offset(k){};
+   Layer(double x, double y, double z, double k):layerphi(x),R(y),eps(z),offset(k){}
    bool operator < (const Layer &a) const
    {
       return layerphi < a.layerphi;
@@ -46,7 +46,7 @@ public:
                         const VolumeID& aVolumeID) const;
   virtual double distanceTrackWire(const CellID& cID, const TVector3& hit_start/*, const TVector3& hit_end*/) const;
 
-  double phi(const CellID& cID) const;
+//  double phi(const CellID& cID) const;
   inline double cell_Size() const { return m_cellSize; }
   inline double epsilon0() const { return m_epsilon0; }
   inline double detectorLength() const { return m_detectorLength; }
@@ -122,6 +122,7 @@ public:
 
 protected:
 
+  double phi(const CellID& cID) const;
   std::map<int,LAYER> layer_params; // <layer, {layerphi, R, eps, offset}>
   std::map<int, std::vector<std::pair<TVector3, TVector3> >> m_wiresPositions; // < layer, vec<WireMidpoint, WireDirection> >
 
diff --git a/Detector/DetSegmentation/src/GridDriftChamber.cpp b/Detector/DetSegmentation/src/GridDriftChamber.cpp
index 3b0032e0da268aad692270744821523b834c39d6..46d601beffd86599453ee9e2c7563308248c4f49 100644
--- a/Detector/DetSegmentation/src/GridDriftChamber.cpp
+++ b/Detector/DetSegmentation/src/GridDriftChamber.cpp
@@ -81,8 +81,8 @@ double GridDriftChamber::distanceTrackWire(const CellID& cID, const TVector3& hi
   double phi_start = phi(cID);
   double phi_end = phi_start + returnAlpha();
 
-  TVector3 Wstart = 10*returnWirePosition(phi_start, -1); // Convert from cm to mm
-  TVector3 Wend = 10*returnWirePosition(phi_end, 1);   // Convert from cm to mm
+  TVector3 Wstart = returnWirePosition(phi_start, -1); // The default centimeter unit in DD4hep
+  TVector3 Wend = returnWirePosition(phi_end, 1);   // The default centimeter unit in DD4hep
 
 //  TVector3 a = hit_end - hit_start;
   TVector3 b = Wend - Wstart;