diff --git a/src/kiri-mode/cam/client.js b/src/kiri-mode/cam/client.js
index 3ac3d1c4..e6abff07 100644
--- a/src/kiri-mode/cam/client.js
+++ b/src/kiri-mode/cam/client.js
@@ -1422,7 +1422,7 @@ CAM.init = function(kiri, api) {
         tolerance: 'camTolerance',
         filter:    'camContourFilter',
         leave:     'camContourLeave',
-        axis:      'X'
+        linear:    'camLatheLinear'
     }).inputs = {
         tool:      UC.newSelect(LANG.cc_tool, {}, "tools"),
         // axis:      UC.newSelect(LANG.cd_axis, {}, "xyaxis"),
@@ -1435,6 +1435,8 @@ CAM.init = function(kiri, api) {
         sep:       UC.newBlank({class:"pop-sep"}),
         tolerance: UC.newInput(LANG.ou_toll_s, {title:LANG.ou_toll_l, convert:UC.toFloat, bound:UC.bound(0,10.0), units:true, round:4}),
         leave:     UC.newInput(LANG.cf_leav_s, {title:LANG.cf_leav_l, convert:UC.toFloat, bound:UC.bound(0,100)}),
+        sep:       UC.newBlank({class:"pop-sep"}),
+        linear:    UC.newBoolean(LANG.ci_line_s, undefined, {title:LANG.ci_line_l}),
         // filter:    UC.newRow([ UC.newButton(LANG.filter, contourFilter) ], {class:"ext-buttons f-row"})
     };
 
diff --git a/src/kiri-mode/cam/tool.js b/src/kiri-mode/cam/tool.js
index aa45cdc6..01e42b78 100644
--- a/src/kiri-mode/cam/tool.js
+++ b/src/kiri-mode/cam/tool.js
@@ -62,6 +62,10 @@ class Tool {
         return this.unitScale() * this.tool.taper_tip;
     }
 
+    maxDiameter() {
+        return Math.max(this.fluteDiameter(), this.tipDiameter(), this.shaftDiameter());
+    }
+
     traceOffset() {
         return (this.isTaperMill() ? this.tipDiameter() : this.fluteDiameter()) / 2;
     }
diff --git a/src/kiri-mode/cam/topo4.js b/src/kiri-mode/cam/topo4.js
index bf94ba9b..090be98d 100644
--- a/src/kiri-mode/cam/topo4.js
+++ b/src/kiri-mode/cam/topo4.js
@@ -73,6 +73,7 @@ class Topo4 {
         this.diam = tool.fluteDiameter();
         this.zoff = widget.track.top || 0;
         this.leave = op.leave || 0;
+        this.linear = op.linear || false;
         this.lineColor = state.settings.controller.dark ? 0xffff00 : 0x555500;
 
         onupdate(0, "lathe");
@@ -363,7 +364,7 @@ class Topo4 {
     }
 
     async latheMinions(onupdate) {
-        const { sliced, tool, zoff, leave, maxo, zBottom, step, resolution } = this;
+        const { sliced, tool, zoff, leave, maxo, zBottom, step, resolution, linear } = this;
         const { putCache, clearCache, queue } = this;
 
         const rota = this.angle * DEG2RAD;
@@ -404,19 +405,34 @@ class Topo4 {
         await Promise.all(promises);
         recs.sort((a, b) => { return b.angle - a.angle });
 
-        count = recs[0].heights.length / 3;
+        // let linear = true;
+
+        count = linear ? recs.length : recs[0].heights.length / 3;
         while (count-- > 0) {
             let slice = newSlice(count);
             slice.camLines = [ newPolygon().setOpen() ];
             paths.push(slice);
         }
 
-        for (let rec of recs) {
-            const { degrees, heights } = rec;
-            [...heights].group(3).forEach((a,i) => {
-                // progress each path 360 degrees to prevent A rolling backwards
-                paths[i].camLines[0].push( newPoint(a[0], a[1], a[2] + leave).setA(degrees + i * -360) );
+        if (linear) {
+            recs.forEach((rec,i) => {
+                const { degrees, heights } = rec;
+                [...heights].group(3).forEach((a) => {
+                    // progress each path 360 degrees to prevent A rolling backwards
+                    paths[i].camLines[0].push( newPoint(a[0], a[1], a[2] + leave).setA(degrees + i * -360) );
+                });
+                if (i % 2 === 1) {
+                    paths[i].camLines[0].reverse();
+                }
             });
+        } else {
+            for (let rec of recs) {
+                const { degrees, heights } = rec;
+                [...heights].group(3).forEach((a,i) => {
+                    // progress each path 360 degrees to prevent A rolling backwards
+                    paths[i].camLines[0].push( newPoint(a[0], a[1], a[2] + leave).setA(degrees + i * -360) );
+                });
+            }
         }
 
         for (let slice of paths) {
@@ -425,9 +441,11 @@ class Topo4 {
                 console.log('empty', slice);
                 continue;
             }
-            // repeat first point 360 degrees progressed
-            const repeat = poly.points[0];
-            slice.camLines[0].push(repeat.clone().setA(repeat.a - 360));
+            if (!linear) {
+                // repeat first point 360 degrees progressed
+                const repeat = poly.points[0];
+                slice.camLines[0].push(repeat.clone().setA(repeat.a - 360));
+            }
             slice.output()
                 .setLayer("lathe", { line: this.lineColor })
                 .addPoly(poly.clone().applyRotations().move({ z: -zoff, x:0, y:0 }));
diff --git a/web/kiri/index.css b/web/kiri/index.css
index 62ba9c90..614a04a3 100644
--- a/web/kiri/index.css
+++ b/web/kiri/index.css
@@ -725,6 +725,7 @@ button:hover {
     right: 0;
     bottom: 0;
     position: fixed;
+    color: black;
     background-color: #fff;
     font-family: 'Russo One', sans-serif;
     z-index: 1000;
diff --git a/web/kiri/lang/en.js b/web/kiri/lang/en.js
index 3a056a29..9ca5b021 100644
--- a/web/kiri/lang/en.js
+++ b/web/kiri/lang/en.js
@@ -607,6 +607,8 @@ self.kiri.lang['en-us'] = {
     ci_abso_l:      "degree rotation is absolute",
     ci_face_s:      "face",
     ci_face_l:      "select face to rotate facing up",
+    ci_line_s:      "linear",
+    ci_line_l:      "make linear passes along X then rotate Y",
 
     // CNC LASER On/Off Operations (Carvera)
     cl_powr_s:      "power",