diff --git a/web/app/3d/craft/brep/wizards/preview-wizard.js b/web/app/3d/craft/brep/wizards/preview-wizard.js
index 4fc09bb1..9c67e3b6 100644
--- a/web/app/3d/craft/brep/wizards/preview-wizard.js
+++ b/web/app/3d/craft/brep/wizards/preview-wizard.js
@@ -11,21 +11,26 @@ export class PreviewWizard extends Wizard {
     this.previewObject = null;
     this.app.viewer.workGroup.add(this.previewGroup);
     this.updatePreview();
+    app.bus.subscribe('refreshSketch', this.onSketchUpdate);
   }
   
+  onSketchUpdate = () => {
+    this.updatePreview();
+  };
+  
   createPreviewObject() {throw 'abstract'};
   
   updatePreview() {
     this.destroyPreviewObject();
     this.previewObject = this.createPreviewObject(this.app, this.readFormFields());
-    if (this.previewObject != null) {
+    if (this.previewObject !== null) {
       this.previewGroup.add( this.previewObject );
     }
     this.app.viewer.render();
   }
 
   destroyPreviewObject() {
-    if (this.previewObject != null) {
+    if (this.previewObject !== null) {
       this.previewGroup.remove( this.previewObject );
       this.previewObject.geometry.dispose();
       this.previewObject = null;
@@ -38,6 +43,7 @@ export class PreviewWizard extends Wizard {
   }
 
   dispose() {
+    this.app.bus.unsubscribe('refreshSketch', this.onSketchUpdate);
     this.destroyPreviewObject();
     this.app.viewer.workGroup.remove(this.previewGroup);
     this.app.viewer.render();
@@ -75,17 +81,7 @@ export class SketchBasedPreviewer {
   create(app, params) {
     const face = app.findFace(params.face);
     if (!face) return null;
-    const needSketchRead = !this.sketch || params.face != this.face;
-    if (needSketchRead) {
-      this.sketch = ReadSketchFromFace(app, face);
-      //for (let polygon of this.sketch) {
-        //if (!Loop.isPolygonCCWOnSurface(polygon, face.surface()) && this.fixToCCW) {
-        //  polygon.reverse();
-        //}
-      //}
-      this.face = params.face;
-    }
-    const triangles = this.createImpl(app, params, this.sketch.fetchContours(), face);
+    const triangles = this.createImpl(app, params, face.sketch.fetchContours(), face);
     return PreviewWizard.createMesh(triangles);
   }
 }
diff --git a/web/app/3d/craft/brep/wizards/wizard.js b/web/app/3d/craft/brep/wizards/wizard.js
index ea8b380d..1798dd67 100644
--- a/web/app/3d/craft/brep/wizards/wizard.js
+++ b/web/app/3d/craft/brep/wizards/wizard.js
@@ -9,7 +9,7 @@ export class Wizard {
     this.formFields = {};
     this.box = this.createUI(opearation, metadata);
     this.overridingHistory = false;
-    if (initialState != undefined) {
+    if (initialState !== undefined) {
       this.setFormFields(initialState);
     }
   }
diff --git a/web/app/3d/craft/sketch/sketch-reader.js b/web/app/3d/craft/sketch/sketch-reader.js
index f378a522..bf458b72 100644
--- a/web/app/3d/craft/sketch/sketch-reader.js
+++ b/web/app/3d/craft/sketch/sketch-reader.js
@@ -15,7 +15,7 @@ class SketchGeom {
   }
 
   fetchContours() {
-    if (this._contours == null) {
+    if (this._contours === null) {
       this._contours = FetchContours(this);
     }
     return this._contours;
@@ -91,7 +91,9 @@ export function ReadSketchPoint(arr) {
 
 export function ReadSketchFromFace(app, face) {
   const savedFace = localStorage.getItem(app.faceStorageKey(face.id));
-  if (savedFace == null) return null;
+  if (savedFace === null) {
+    return null;
+  }
   return ReadSketch(JSON.parse(savedFace), face.id, true);
 }
 
diff --git a/web/app/3d/modeler-app.js b/web/app/3d/modeler-app.js
index 7bc5cf25..2e02d4c3 100644
--- a/web/app/3d/modeler-app.js
+++ b/web/app/3d/modeler-app.js
@@ -622,12 +622,7 @@ App.prototype.findSketches = function(solid) {
 };
 
 App.prototype.refreshSketchOnFace = function(sketchFace) {
-  var faceStorageKey = this.faceStorageKey(sketchFace.id);
-  var savedFace = localStorage.getItem(faceStorageKey);
-  if (savedFace != null) {
-    var geom = ReadSketch(JSON.parse(savedFace), sketchFace.id, true);
-    sketchFace.syncSketches(geom);
-  }
+  sketchFace.updateSketch(this);
 };
 
 App.prototype.save = function() {
diff --git a/web/app/3d/scene/scene-object.js b/web/app/3d/scene/scene-object.js
index 8213696a..a2f07207 100644
--- a/web/app/3d/scene/scene-object.js
+++ b/web/app/3d/scene/scene-object.js
@@ -4,6 +4,7 @@ import Counters from '../counters'
 import {Matrix3, BasisForPlane} from '../../math/l3space'
 import {isCurveClass} from '../cad-utils'
 import DPR from '../../utils/dpr'
+import {ReadSketch, ReadSketchFromFace} from "../craft/sketch/sketch-reader";
 
 export class SceneSolid {
   
@@ -22,6 +23,8 @@ export class SceneSolid {
     this.mergeable = true;
     this.sceneFaces = [];
 
+    this.sketch = null;
+    
     this.material = createSolidMaterial(skin);
   }
 
@@ -113,8 +116,24 @@ export class SceneFace {
     threeFace.__TCAD_SceneFace = this;
   }
 
-  syncSketches(geom) {
-    if (this.sketch3DGroup != null) {
+  readSketchGeom(app) {
+    let faceStorageKey = app.faceStorageKey(this.id);
+    let savedFace = localStorage.getItem(faceStorageKey);
+    if (savedFace === null) {
+      return null;
+    }
+    return ReadSketch(JSON.parse(savedFace), this.id, true);
+  }
+
+  updateSketch(app) {
+    this.sketch = this.readSketchGeom(app);
+    if (this.sketch !== null) {
+      this.syncSketch(this.sketch);
+    }
+  }
+  
+  syncSketch(geom) {
+    if (this.sketch3DGroup !== null) {
       for (let i = this.sketch3DGroup.children.length - 1; i >= 0; --i) {
         this.sketch3DGroup.remove(this.sketch3DGroup.children[i]);
       }
@@ -123,10 +142,9 @@ export class SceneFace {
       this.solid.cadGroup.add(this.sketch3DGroup);
     }
 
-    const basis = this.basis();
-    const _3dTransformation = new Matrix3().setBasis(basis);
-    //we lost depth or z off in 2d sketch, calculate it again
-    const depth = this.depth();
+    let surface = this.surface();
+    let [u, v] = surface.middle();
+    const _3dTransformation =  surface.tangentPlane(u, v).get3DTransformation();
     const addSketchObjects = (sketchObjects, material, close) => {
       for (let sketchObject of sketchObjects) {
         let line = new THREE.Line(undefined, material);
@@ -134,7 +152,6 @@ export class SceneFace {
         const chunks = sketchObject.approximate(10);
         function addLine(p, q) {
           const lg = line.geometry;
-          chunks[p].z = chunks[q].z = depth;
           const a = _3dTransformation.apply(chunks[p]);
           const b = _3dTransformation.apply(chunks[q]);
 
@@ -153,7 +170,7 @@ export class SceneFace {
   }
 
   findById(sketchObjectId) {
-    return this.sketch3DGroup.children.find(o => o.__TCAD_SketchObject && o.__TCAD_SketchObject.id == sketchObjectId);
+    return this.sketch3DGroup.children.find(o => o.__TCAD_SketchObject && o.__TCAD_SketchObject.id === sketchObjectId);
   }
 
   getSketchObjectVerticesIn3D(sketchObjectId) {
diff --git a/web/app/brep/geom/impl/nurbs.js b/web/app/brep/geom/impl/nurbs.js
index 3a31cab3..c357b029 100644
--- a/web/app/brep/geom/impl/nurbs.js
+++ b/web/app/brep/geom/impl/nurbs.js
@@ -291,6 +291,15 @@ export class NurbsSurface extends Surface {
     this.simpleSurface = simpleSurface || figureOutSimpleSurface(this); 
   }
 
+  middle() {
+    let {min: uMin, max: uMax} = this.verb.domainU();
+    let {min: vMin, max: vMax} = this.verb.domainV();
+    return [
+      (uMax - uMin) * 0.5,
+      (vMax - vMin) * 0.5
+    ];
+  }
+  
   toNurbs() {
     return this;
   }
diff --git a/web/app/brep/geom/impl/plane.js b/web/app/brep/geom/impl/plane.js
index ce23e425..41a2c6cc 100644
--- a/web/app/brep/geom/impl/plane.js
+++ b/web/app/brep/geom/impl/plane.js
@@ -46,7 +46,7 @@ export class Plane extends Surface {
     if (!this.__3dTr) {
       const basis = new Matrix3().setBasis(this.basis());
       const translate = new Matrix3();
-      translate.tz = this.w
+      translate.tz = this.w;
       this.__3dTr = basis.combine(translate);
 //      this.__3dTr.tz = this.w;
     }