diff --git a/src/fvMotionSolver/pointPatchFields/derived/surfaceSlipDisplacement/surfaceSlipDisplacementPointPatchVectorField.C b/src/fvMotionSolver/pointPatchFields/derived/surfaceSlipDisplacement/surfaceSlipDisplacementPointPatchVectorField.C
index 68e0151f85..9876dcb319 100644
--- a/src/fvMotionSolver/pointPatchFields/derived/surfaceSlipDisplacement/surfaceSlipDisplacementPointPatchVectorField.C
+++ b/src/fvMotionSolver/pointPatchFields/derived/surfaceSlipDisplacement/surfaceSlipDisplacementPointPatchVectorField.C
@@ -52,6 +52,254 @@ const NamedEnum<surfaceSlipDisplacementPointPatchVectorField::followMode, 3>
     surfaceSlipDisplacementPointPatchVectorField::followModeNames_;
 
 
+// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
+
+void surfaceSlipDisplacementPointPatchVectorField::calcProjection
+(
+    vectorField& displacement
+) const
+{
+    const polyMesh& mesh = patch().boundaryMesh().mesh()();
+    const pointField& localPoints = patch().localPoints();
+    const labelList& meshPoints = patch().meshPoints();
+
+    //const scalar deltaT = mesh.time().deltaT().value();
+
+    // Construct large enough vector in direction of projectDir so
+    // we're guaranteed to hit something.
+
+    //- Per point projection vector:
+    const scalar projectLen = mag(mesh.bounds().max()-mesh.bounds().min());
+
+    // For case of fixed projection vector:
+    vector projectVec;
+    if (projectMode_ == FIXEDNORMAL)
+    {
+        vector n = projectDir_/mag(projectDir_);
+        projectVec = projectLen*n;
+    }
+
+
+    // Get fixed points (bit of a hack)
+    const pointZone* zonePtr = NULL;
+
+    if (frozenPointsZone_.size() > 0)
+    {
+        const pointZoneMesh& pZones = mesh.pointZones();
+
+        zonePtr = &pZones[pZones.findZoneID(frozenPointsZone_)];
+
+        Pout<< "surfaceSlipDisplacementPointPatchVectorField : Fixing all "
+            << zonePtr->size() << " points in pointZone " << zonePtr->name()
+            << endl;
+    }
+
+    // Get the starting locations from the motionSolver
+    const displacementLaplacianFvMotionSolver& motionSolver =
+        mesh.lookupObject<displacementLaplacianFvMotionSolver>
+        (
+            "dynamicMeshDict"
+        );
+    const pointField& points0 = motionSolver.points0();
+
+
+    pointField start(meshPoints.size());
+    forAll(start, i)
+    {
+        start[i] = points0[meshPoints[i]] + displacement[i];
+    }
+
+    label nNotProjected = 0;
+
+    if (projectMode_ == NEAREST)
+    {
+        List<pointIndexHit> nearest;
+        labelList hitSurfaces;
+        surfaces().findNearest
+        (
+            start,
+            scalarField(start.size(), sqr(projectLen)),
+            hitSurfaces,
+            nearest
+        );
+
+        forAll(nearest, i)
+        {
+            if (zonePtr && (zonePtr->whichPoint(meshPoints[i]) >= 0))
+            {
+                // Fixed point. Reset to point0 location.
+                displacement[i] = points0[meshPoints[i]] - localPoints[i];
+            }
+            else if (nearest[i].hit())
+            {
+                displacement[i] =
+                    nearest[i].hitPoint()
+                  - points0[meshPoints[i]];
+            }
+            else
+            {
+                nNotProjected++;
+
+                if (debug)
+                {
+                    Pout<< "    point:" << meshPoints[i]
+                        << " coord:" << localPoints[i]
+                        << "  did not find any surface within " << projectLen
+                        << endl;
+                }
+            }
+        }
+    }
+    else
+    {
+        // Do tests on all points. Combine later on.
+
+        // 1. Check if already on surface
+        List<pointIndexHit> nearest;
+        {
+            labelList nearestSurface;
+            surfaces().findNearest
+            (
+                start,
+                scalarField(start.size(), sqr(SMALL)),
+                nearestSurface,
+                nearest
+            );
+        }
+
+        // 2. intersection. (combined later on with information from nearest
+        // above)
+        vectorField projectVecs(start.size(), projectVec);
+
+        if (projectMode_ == POINTNORMAL)
+        {
+            projectVecs = projectLen*patch().pointNormals();
+        }
+
+        // Knock out any wedge component
+        scalarField offset(start.size(), 0.0);
+        if (wedgePlane_ >= 0 && wedgePlane_ <= vector::nComponents)
+        {
+            forAll(offset, i)
+            {
+                offset[i] = start[i][wedgePlane_];
+                start[i][wedgePlane_] = 0;
+                projectVecs[i][wedgePlane_] = 0;
+            }
+        }
+
+        List<pointIndexHit> rightHit;
+        {
+            labelList rightSurf;
+            surfaces().findAnyIntersection
+            (
+                start,
+                start+projectVecs,
+                rightSurf,
+                rightHit
+            );
+        }
+        
+        List<pointIndexHit> leftHit;
+        {
+            labelList leftSurf;
+            surfaces().findAnyIntersection
+            (
+                start,
+                start-projectVecs,
+                leftSurf,
+                leftHit
+            );
+        }
+
+        // 3. Choose either -fixed, nearest, right, left.
+        forAll(displacement, i)
+        {
+            if (zonePtr && (zonePtr->whichPoint(meshPoints[i]) >= 0))
+            {
+                // Fixed point. Reset to point0 location.
+                displacement[i] = points0[meshPoints[i]] - localPoints[i];
+            }
+            else if (nearest[i].hit())
+            {
+                // Found nearest.
+                displacement[i] =
+                    nearest[i].hitPoint()
+                  - points0[meshPoints[i]];
+            }
+            else
+            {
+                pointIndexHit interPt;
+
+                if (rightHit[i].hit())
+                {
+                    if (leftHit[i].hit())
+                    {
+                        if
+                        (
+                            magSqr(rightHit[i].hitPoint()-start[i])
+                          < magSqr(leftHit[i].hitPoint()-start[i])
+                        )
+                        {
+                            interPt = rightHit[i];
+                        }
+                        else
+                        {
+                            interPt = leftHit[i];
+                        }
+                    }
+                    else
+                    {
+                        interPt = rightHit[i];
+                    }
+                }
+                else
+                {
+                    if (leftHit[i].hit())
+                    {
+                        interPt = leftHit[i];
+                    }
+                }
+
+
+                if (interPt.hit())
+                {
+                    if (wedgePlane_ >= 0 && wedgePlane_ <= vector::nComponents)
+                    {
+                        interPt.rawPoint()[wedgePlane_] += offset[i];
+                    }
+                    displacement[i] = interPt.rawPoint()-points0[meshPoints[i]];
+                }
+                else
+                {
+                    nNotProjected++;
+
+                    if (debug)
+                    {
+                        Pout<< "    point:" << meshPoints[i]
+                            << " coord:" << localPoints[i]
+                            << "  did not find any intersection between"
+                            << " ray from " << start[i]-projectVecs[i]
+                            << " to " << start[i]+projectVecs[i] << endl;
+                    }
+                }
+            }
+        }
+    }
+
+    reduce(nNotProjected, sumOp<label>());
+
+    if (nNotProjected > 0)
+    {
+        Info<< "surfaceSlipDisplacement :"
+            << " on patch " << patch().name()
+            << " did not project " << nNotProjected
+            << " out of " << returnReduce(localPoints.size(), sumOp<label>())
+            << " points." << endl;
+    }
+}
+
+
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
 surfaceSlipDisplacementPointPatchVectorField::
@@ -81,7 +329,7 @@ surfaceSlipDisplacementPointPatchVectorField
     projectMode_(followModeNames_.read(dict.lookup("followMode"))),
     projectDir_(dict.lookup("projectDirection")),
     wedgePlane_(readLabel(dict.lookup("wedgePlane"))),
-    frozenPointsZone_(dict.lookup("frozenPointsZone"))
+    frozenPointsZone_(dict.lookupOrDefault("frozenPointsZone", word::null))
 {}
 
 
@@ -167,229 +415,10 @@ void surfaceSlipDisplacementPointPatchVectorField::evaluate
     const Pstream::commsTypes commsType
 )
 {
-    const polyMesh& mesh = patch().boundaryMesh().mesh()();
-
-    // const scalar deltaT = mesh.time().deltaT().value();
-
-    // Construct large enough vector in direction of projectDir so
-    // we're guaranteed to hit something.
-
-    const scalar projectLen = mesh.bounds().mag();
-
-    // For case of fixed projection vector:
-    vector projectVec;
-    if (projectMode_ == FIXEDNORMAL)
-    {
-        vector n = projectDir_/mag(projectDir_);
-        projectVec = projectLen*n;
-    }
-
-    //- Per point projection vector:
-
-    const pointField& localPoints = patch().localPoints();
-    const labelList& meshPoints = patch().meshPoints();
-
     vectorField displacement(this->patchInternalField());
 
-
-    // Get fixed points (bit of a hack)
-    const pointZone* zonePtr = NULL;
-
-    if (frozenPointsZone_.size())
-    {
-        const pointZoneMesh& pZones = mesh.pointZones();
-
-        zonePtr = &pZones[pZones.findZoneID(frozenPointsZone_)];
-
-        Pout<< "surfaceSlipDisplacementPointPatchVectorField : Fixing all "
-            << zonePtr->size() << " points in pointZone " << zonePtr->name()
-            << endl;
-    }
-
-    // Get the starting locations from the motionSolver
-    const displacementLaplacianFvMotionSolver& motionSolver =
-        mesh.lookupObject<displacementLaplacianFvMotionSolver>
-        (
-            "dynamicMeshDict"
-        );
-    const pointField& points0 = motionSolver.points0();
-
-
-//XXXXXX
-
-
-    pointField start(meshPoints.size());
-    forAll(start, i)
-    {
-        start[i] = points0[meshPoints[i]] + displacement[i];
-    }
-
-    if (projectMode_ == NEAREST)
-    {
-        List<pointIndexHit> nearest;
-        labelList hitSurfaces;
-        surfaces().findNearest
-        (
-            start,
-            scalarField(start.size(), sqr(projectLen)),
-            hitSurfaces,
-            nearest
-        );
-
-        forAll(nearest, i)
-        {
-            if (zonePtr && (zonePtr->whichPoint(meshPoints[i]) >= 0))
-            {
-                // Fixed point. Reset to point0 location.
-                displacement[i] = points0[meshPoints[i]] - localPoints[i];
-            }
-            else if (nearest[i].hit())
-            {
-                displacement[i] =
-                    nearest[i].hitPoint()
-                  - points0[meshPoints[i]];
-            }
-            else
-            {
-                Pout<< "    point:" << meshPoints[i]
-                    << " coord:" << localPoints[i]
-                    << "  did not find any surface within " << projectLen
-                    << endl;
-            }
-        }
-    }
-    else
-    {
-        // Do tests on all points. Combine later on.
-
-        // 1. Check if already on surface
-        List<pointIndexHit> nearest;
-        {
-            labelList nearestSurface;
-            surfaces().findNearest
-            (
-                start,
-                scalarField(start.size(), sqr(SMALL)),
-                nearestSurface,
-                nearest
-            );
-        }
-
-        // 2. intersection. (combined later on with information from nearest
-        // above)
-        vectorField projectVecs(start.size(), projectVec);
-
-        if (projectMode_ == POINTNORMAL)
-        {
-            projectVecs = projectLen*patch().pointNormals();
-        }
-
-        // Knock out any wedge component
-        scalarField offset(start.size(), 0.0);
-        if (wedgePlane_ >= 0 && wedgePlane_ <= vector::nComponents)
-        {
-            forAll(offset, i)
-            {
-                offset[i] = start[i][wedgePlane_];
-                start[i][wedgePlane_] = 0;
-                projectVecs[i][wedgePlane_] = 0;
-            }
-        }
-
-        List<pointIndexHit> rightHit;
-        {
-            labelList rightSurf;
-            surfaces().findAnyIntersection
-            (
-                start,
-                start+projectVecs,
-                rightSurf,
-                rightHit
-            );
-        }
-
-        List<pointIndexHit> leftHit;
-        {
-            labelList leftSurf;
-            surfaces().findAnyIntersection
-            (
-                start,
-                start-projectVecs,
-                leftSurf,
-                leftHit
-            );
-        }
-
-        // 3. Choose either -fixed, nearest, right, left.
-        forAll(displacement, i)
-        {
-            if (zonePtr && (zonePtr->whichPoint(meshPoints[i]) >= 0))
-            {
-                // Fixed point. Reset to point0 location.
-                displacement[i] = points0[meshPoints[i]] - localPoints[i];
-            }
-            else if (nearest[i].hit())
-            {
-                // Found nearest.
-                displacement[i] =
-                    nearest[i].hitPoint()
-                  - points0[meshPoints[i]];
-            }
-            else
-            {
-                pointIndexHit interPt;
-
-                if (rightHit[i].hit())
-                {
-                    if (leftHit[i].hit())
-                    {
-                        if
-                        (
-                            magSqr(rightHit[i].hitPoint()-start[i])
-                          < magSqr(leftHit[i].hitPoint()-start[i])
-                        )
-                        {
-                            interPt = rightHit[i];
-                        }
-                        else
-                        {
-                            interPt = leftHit[i];
-                        }
-                    }
-                    else
-                    {
-                        interPt = rightHit[i];
-                    }
-                }
-                else
-                {
-                    if (leftHit[i].hit())
-                    {
-                        interPt = leftHit[i];
-                    }
-                }
-
-
-                if (interPt.hit())
-                {
-                    if (wedgePlane_ >= 0 && wedgePlane_ <= vector::nComponents)
-                    {
-                        interPt.rawPoint()[wedgePlane_] += offset[i];
-                    }
-                    displacement[i] = interPt.rawPoint()-points0[meshPoints[i]];
-                }
-                else
-                {
-                    Pout<< "    point:" << meshPoints[i]
-                        << " coord:" << localPoints[i]
-                        << "  did not find any intersection between ray from "
-                        << start[i]-projectVecs[i]
-                        << " to " << start[i]+projectVecs[i]
-                        << endl;
-                }
-            }
-        }
-    }
+    // Calculate displacement to project points onto surface
+    calcProjection(displacement);
 
     // Get internal field to insert values into
     Field<vector>& iF = const_cast<Field<vector>&>(this->internalField());
@@ -412,8 +441,11 @@ void surfaceSlipDisplacementPointPatchVectorField::write(Ostream& os) const
         << token::END_STATEMENT << nl;
     os.writeKeyword("wedgePlane") << wedgePlane_
         << token::END_STATEMENT << nl;
-    os.writeKeyword("frozenPointsZone") << frozenPointsZone_
-        << token::END_STATEMENT << nl;
+    if (frozenPointsZone_ != word::null)
+    {
+        os.writeKeyword("frozenPointsZone") << frozenPointsZone_
+            << token::END_STATEMENT << nl;
+    }
 }
 
 
diff --git a/src/fvMotionSolver/pointPatchFields/derived/surfaceSlipDisplacement/surfaceSlipDisplacementPointPatchVectorField.H b/src/fvMotionSolver/pointPatchFields/derived/surfaceSlipDisplacement/surfaceSlipDisplacementPointPatchVectorField.H
index d74ca862e2..9edb42ac0d 100644
--- a/src/fvMotionSolver/pointPatchFields/derived/surfaceSlipDisplacement/surfaceSlipDisplacementPointPatchVectorField.H
+++ b/src/fvMotionSolver/pointPatchFields/derived/surfaceSlipDisplacement/surfaceSlipDisplacementPointPatchVectorField.H
@@ -107,6 +107,9 @@ private:
 
     // Private Member Functions
 
+        //- Calculate displacement to project onto surface
+        void calcProjection(vectorField& displacement) const;
+
         //- Disallow default bitwise assignment
         void operator=(const surfaceSlipDisplacementPointPatchVectorField&);