diff --git a/src/add/array.js b/src/add/array.js
index 690823d4..3d7dbd14 100644
--- a/src/add/array.js
+++ b/src/add/array.js
@@ -34,9 +34,13 @@
      * @param v
      * @returns {Array}
      */
-    AP.append = function(v) {
-        this.push(v);
-        return this;
+    AP.append = function(v, flat) {
+        if (flat) {
+            return this.appendAll(v);
+        } else {
+            this.push(v);
+            return this;
+        }
     };
 
     /**
diff --git a/src/geo/polygons.js b/src/geo/polygons.js
index 0735f0e6..d9b62c9f 100644
--- a/src/geo/polygons.js
+++ b/src/geo/polygons.js
@@ -520,17 +520,17 @@
 
         // if specified, perform offset gap analysis
         if (opt.gaps && polys.length) {
-            let negoff = offset(polys, -offs, {
+            let oneg = offset(polys, -offs, {
                 fill: opt.fill, join: opt.join, type: opt.type, z: opt.z, minArea: mina
             });
             let suba = [];
-            let diff = subtract(orig, negoff, suba, null, zed);
-            opt.gaps.push(suba);
+            let diff = subtract(orig, oneg, suba, null, zed);
+            opt.gaps.append(suba, opt.flat);
         }
 
         // if offset fails, consider last polygons as gap areas
         if (opt.gaps && !polys.length) {
-            opt.gaps.push(orig);
+            opt.gaps.append(orig, opt.flat);
         }
 
         // if specified, perform up to *count* successive offsets
@@ -538,7 +538,7 @@
             // ensure opts has offset accumulator array
             opt.outs = opt.outs || [];
             // store polys in accumulator
-            opt.outs.push(polys);
+            opt.outs.append(polys, opt.flat);
             if (opt.count > 1) {
                 // decrement count, increment depth
                 opt.count--;
diff --git a/src/kiri/conf.js b/src/kiri/conf.js
index ec5ffc53..e9452959 100644
--- a/src/kiri/conf.js
+++ b/src/kiri/conf.js
@@ -437,7 +437,7 @@
                     camTabsOn: false,
                     camRoughPocket: false,   // camPocketOnlyRough
                     camOutlinePocket: false, // camPocketOnlyFinish
-                    camDepthFirst: true,
+                    camDepthFirst: false,
                     camWideCutout: false,
                     camEaseDown: false,
                     camOriginTop: true,
diff --git a/src/mode/cam/driver.js b/src/mode/cam/driver.js
index b2be8b4b..b8fe841e 100644
--- a/src/mode/cam/driver.js
+++ b/src/mode/cam/driver.js
@@ -693,10 +693,12 @@
         }
 
         // clone and flatten the shell with tops to offset array
-        shell.clone(true).forEach(function(poly) { poly.setZ(slice.z).flattenTo(offset) });
+        shell.clone(true).forEach(function(poly) {
+            poly.setZ(slice.z).flattenTo(offset);
+        });
         POLY.flatten(tops, offset, true);
 
-        // only tab cut polys should be open
+        // only tab cut polys should be open (happens later)
         offset.forEach(function(trace) {
             trace.setClosed();
         });
@@ -705,7 +707,12 @@
         offset = POLY.nest(offset);
 
         // inset offset array by 1/2 diameter then by tool overlap %
-        POLY.expand(offset, - (diameter / 2 + stock), slice.z, outer, 0, -diameter * overlap);
+        POLY.offset(offset, [-(diameter / 2 + stock), -diameter * overlap], {
+            z: slice.z,
+            count: 999,
+            flat: true,
+            outs: outer
+        });
 
         if (!pocket) {
             // re-flatten offset polys
@@ -718,7 +725,7 @@
             // re-nest offset polys
             // outer = POLY.nest(offset);
             outer = offset;
-            // more outer
+            // add another wider pass to the cutout polygon(s)
             if (widecut) {
                 POLY.expand(offset, diameter * overlap, slice.z, outer, 1);
             }