diff --git a/src/geo/point.js b/src/geo/point.js
index f346980a..b441af28 100644
--- a/src/geo/point.js
+++ b/src/geo/point.js
@@ -50,6 +50,11 @@ class Point {
         return this;
     }
 
+    setA(a) {
+        this.a = a;
+        return this;
+    }
+
     swapXZ() {
         let p = this,
             t = p.x;
diff --git a/src/geo/polygon.js b/src/geo/polygon.js
index 9b92a220..2cdbb542 100644
--- a/src/geo/polygon.js
+++ b/src/geo/polygon.js
@@ -824,6 +824,18 @@ class Polygon {
         return this;
     }
 
+    setA(a) {
+        for (let p of this.points) {
+            p.setA(a);
+        }
+        if (this.inner) {
+            for (let inner of this.inner) {
+                inner.setA(a);
+            }
+        }
+        return this;
+    }
+
     /**
      * set all points' z value
      *
diff --git a/src/kiri-mode/cam/ops.js b/src/kiri-mode/cam/ops.js
index 755f6e85..329d5ba5 100644
--- a/src/kiri-mode/cam/ops.js
+++ b/src/kiri-mode/cam/ops.js
@@ -854,22 +854,17 @@ class OpLathe extends CamOp {
 
     prepare(ops, progress) {
         let { op, state, slices, topo } = this;
-        let { settings, widget } = state;
-        let { process } = settings;
+        let { settings } = state;
 
-        let { setTolerance, setTool, setSpindle, setPrintPoint } = ops;
+        let { setTool, setSpindle, setPrintPoint } = ops;
         let { camOut, newLayer, polyEmit, printPoint, lastPoint } = ops;
         let { bounds, zmax } = ops;
 
         let toolDiam = new CAM.Tool(settings, op.tool).fluteDiameter();
         let stepover = toolDiam * op.step * 2;
-        let cutdir = process.camConventional;
-        let depthFirst = process.camDepthFirst;
-        let depthData = [];
 
         setTool(op.tool, op.rate, op.plunge);
         setSpindle(op.spindle);
-        setTolerance(topo.tolerance);
 
         // start top center, X = 0, Y = 0 closest to 4th axis chuck
         printPoint = newPoint(0, 0, zmax);
diff --git a/src/kiri-mode/cam/slice.js b/src/kiri-mode/cam/slice.js
index 973364f1..96ad25cc 100644
--- a/src/kiri-mode/cam/slice.js
+++ b/src/kiri-mode/cam/slice.js
@@ -241,7 +241,7 @@ CAM.slice = async function(settings, widget, onupdate, ondone) {
         tracker.rotation = isIndexed ? axisRotation : 0;
         // setup new state when indexing the workspace
         if (true && op.op.type === "index") {
-            let points = base.verticesToPoints();
+            // let points = base.verticesToPoints();
             state.slicer = new kiri.cam_slicer(widget);
             shadows = {};
             new CAM.OPS.shadow(state, { type: "shadow", silent: true }).slice(progress => {
diff --git a/src/kiri-mode/cam/topo.js b/src/kiri-mode/cam/topo.js
index d6425c91..1605e5aa 100644
--- a/src/kiri-mode/cam/topo.js
+++ b/src/kiri-mode/cam/topo.js
@@ -36,7 +36,7 @@ class Topo {
             contourY = axis === "y",
             bounds = widget.getBoundingBox().clone(),
             tolerance = contour.tolerance,
-            flatness = contour.flatness || 0.005,
+            flatness = contour.flatness || 0.001,
             shadow = tshadow,
             minX = bounds.min.x,
             maxX = bounds.max.x,
diff --git a/src/kiri-mode/cam/topo4.js b/src/kiri-mode/cam/topo4.js
index 9771e97d..751aa6fc 100644
--- a/src/kiri-mode/cam/topo4.js
+++ b/src/kiri-mode/cam/topo4.js
@@ -287,15 +287,21 @@ class Topo4 {
         for (let rec of recs) {
             const { angle, heights } = rec;
             const points = heights.toFloat32();
-            rotatePoints(points, new THREE.Matrix4().makeRotationAxis(axis, angle));
 
             const poly = newPolygon().setOpen().addPoints(
+                [...points].group(3).map(a => newPoint(a[0], a[1], a[2]).setA(angle))
+            );
+
+            rotatePoints(points, new THREE.Matrix4().makeRotationAxis(axis, angle));
+            const top = newPolygon().setOpen().addPoints(
                 [...points].group(3).map(a => newPoint(a[0], a[1], a[2]))
             );
-            const slice = newSlice().addTops([ poly ]);
+
+            const slice = newSlice().addTops([ top ]);
+            slice.camLines = [ poly ];
             slice.output()
                 .setLayer("lathe", { line: 0xffff00 })
-                .addPoly(poly);
+                .addPoly(top);
 
             paths.push(slice);
         }