diff --git a/src/kiri/core/conf.js b/src/kiri/core/conf.js
index 4df29f63..86f10e4e 100644
--- a/src/kiri/core/conf.js
+++ b/src/kiri/core/conf.js
@@ -428,6 +428,7 @@ export const conf = {
                 camAreaMode: "clear",
                 camAreaTrace: "none",
                 camAreaSurface: "linear",
+                camAreaAngle: 0,
                 camAreaOver: 0.4,
                 camAreaDown: 1,
                 camAreaSpeed: 1000,
diff --git a/src/kiri/mode/cam/cl-ops.js b/src/kiri/mode/cam/cl-ops.js
index fbef8211..ac413b97 100644
--- a/src/kiri/mode/cam/cl-ops.js
+++ b/src/kiri/mode/cam/cl-ops.js
@@ -661,16 +661,22 @@ export function createPopOps() {
     function isTrace() {
         return env.poppedRec.mode === 'trace';
     }
+
     function isSurface() {
         return env.poppedRec.mode === 'surface';
     }
 
+    function isSurfaceLinear() {
+        return env.poppedRec.mode === 'surface' && env.poppedRec.sr_typ === 'linear';
+    }
+
     createPopOp('area', {
         spindle: 'camAreaSpindle',
         tool: 'camAreaTool',
         mode: 'camAreaMode',
         tr_off: 'camAreaTrace',
-        sr_typ: 'camAreaSurface',
+        sr_type: 'camAreaSurface',
+        sr_angle: 'camAreaAngle',
         over: 'camAreaOver',
         down: 'camAreaDown',
         rate: 'camAreaSpeed',
@@ -687,7 +693,7 @@ export function createPopOps() {
         tool: UC.newSelect(LANG.cc_tool, {}, "tools"),
         mode: UC.newSelect(LANG.mo_menu, {}, "opmode"),
         tr_off: UC.newSelect(LANG.cc_offs_s, { title: LANG.cc_offs_l, show: isTrace }, "traceoff"),
-        sr_typ: UC.newSelect("pattern", { title: "pattern", show: isSurface }, "surftyp"),
+        sr_type: UC.newSelect("pattern", { title: "pattern", show: isSurface }, "surftyp"),
         sep: UC.newBlank({ class: "pop-sep" }),
         menu: UC.newRow([
             UC.newButton("edge", traceAdd),
@@ -696,7 +702,8 @@ export function createPopOps() {
         outline: UC.newBoolean(LANG.cp_outl_s, undefined, { title: LANG.cp_outl_l, show: () => isClear() || isTrace() }),
         expand: UC.newInput(LANG.cp_xpnd_s, { title: LANG.cp_xpnd_l, convert: toFloat, units }),
         sep: UC.newBlank({ class: "pop-sep" }),
-        over: UC.newInput(LANG.cc_sovr_s, { title: LANG.cc_sovr_l, convert: toFloat, bound: UC.bound(0.001, 100.0), units, show: () => isClear() || isSurface() }),
+        sr_angle: UC.newInput("step angle", { title: "step angle", convert: toFloat, bound: UC.bound(0, 360), show: isSurfaceLinear }),
+        over: UC.newInput(LANG.cc_sovr_s, { title: LANG.cc_sovr_l, convert: toFloat, bound: UC.bound(0.001, 100.0), show: () => isClear() || isSurface() }),
         down: UC.newInput(LANG.cc_sdwn_s, { title: LANG.cc_sdwn_l, convert: toFloat, bound: UC.bound(0, 100.0), units, show: () => isClear() || isTrace() }),
         sep: UC.newBlank({ class: "pop-sep", show: isSurface }),
         refine: UC.newInput(LANG.cp_refi_s, { title: LANG.cp_refi_l, convert: toInt, show: isSurface }),
diff --git a/src/kiri/mode/cam/op-area.js b/src/kiri/mode/cam/op-area.js
index fe6ff427..dff124ac 100644
--- a/src/kiri/mode/cam/op-area.js
+++ b/src/kiri/mode/cam/op-area.js
@@ -20,7 +20,7 @@ class OpArea extends CamOp {
     async slice(progress) {
         const pocket = this;
         let { op, state } = this;
-        let { tool, mode, down, over, follow, expand, tr_off, sr_typ, outline, refine, smooth, tolerance } = op;
+        let { tool, mode, down, over, follow, expand, outline, refine, smooth } = op;
         let { ov_topz, ov_botz, ov_conv } = op;
         let { settings, widget, tabs, color } = state;
         let { addSlices, setToolDiam, cutTabs, healPolys, shadowAt, workarea } = state;
@@ -158,6 +158,7 @@ class OpArea extends CamOp {
                 progress(proc, 'clear');
             } else
             if (mode === 'trace') {
+                let { tr_type  } = op;
                 let zs = down ? base_util.lerp(zTop, bounds.min.z, down) : [ bounds.min.z ];
                 let zroc = 0;
                 let zinc = 1 / zs.length;
@@ -166,10 +167,11 @@ class OpArea extends CamOp {
                     let slice = newLayer();
                     let layers = slice.output();
                     let outs = [];
-                    if (tr_off === 'none') {
-                        outs = [ area.clone().setZ(z) ];
+                    if (tr_type === 'none') {
+                        area = area.clone(true);
+                        outs = [ zs.length > 1 ? area.setZ(z) : area ];
                     } else {
-                        POLY.offset([ area ], tr_off === 'inside' ? [ -toolDiam / 2 ] : [ toolDiam / 2 ], {
+                        POLY.offset([ area ], tr_type === 'inside' ? [ -toolDiam / 2 ] : [ toolDiam / 2 ], {
                             count: 1, outs, flat: true, z, minArea: 0
                         });
                     }
@@ -191,10 +193,12 @@ class OpArea extends CamOp {
                 progress(proc, 'trace');
             } else
             if (mode === 'surface') {
-                if (sr_typ === 'linear') {
+                let { sr_type, sr_angle, tolerance } = op;
 
+                if (sr_type === 'linear') {
+                    console.log({ sr_angle });
                 } else
-                if (sr_typ === 'offset') {
+                if (sr_type === 'offset') {
 
                 }
             }