diff --git a/src/geo/polygon.js b/src/geo/polygon.js
index 8ff28826..9338031d 100644
--- a/src/geo/polygon.js
+++ b/src/geo/polygon.js
@@ -1306,6 +1306,15 @@
         if (clip.Execute(ctyp.ctUnion, ctre, cfil.pftEvenOdd, cfil.pftEvenOdd)) {
             let union = POLY().fromClipperTreeUnion(ctre, poly.getZ(), minarea);
             if (all) {
+                if (union.length === 2) {
+                    // TODO look for faster equivalence check. area? perimeter?
+                    let src = [this, poly].sort((a,b) => { return a.area() - b.area() });
+                    let dst = union.sort((a,b) => { return a.area() - b.area() });
+                    if (src[0].isEquivalent(dst[0]) && src[1].isEquivalent(dst[1])) {
+                        return null;
+                    }
+                    return union;
+                }
                 return union;
             }
             if (union.length === 1) {
@@ -1313,7 +1322,7 @@
                 union.fillang = fillang;
                 return union;
             } else {
-                console.log({check_union_call_path: union});
+                console.log({check_union_call_path: union, this: this, poly});
             }
         }
 
diff --git a/src/kiri/print.js b/src/kiri/print.js
index 969ddb04..8679da3e 100644
--- a/src/kiri/print.js
+++ b/src/kiri/print.js
@@ -1064,8 +1064,8 @@
                 // - it has more than one sibling
                 // - it has no parent (top/outer most)
                 // - it is offset from its parent by more than diameter
-                // if (poly.isOpen() || !poly.parent || poly.parent.innerCount() > 1 || !polygonWithinOffset(poly, poly.parent, offset)) {
-                if (poly.depth === 0) {
+                if (poly.isOpen() || !poly.parent || poly.parent.innerCount() > 1 || !polygonWithinOffset(poly, poly.parent, offset)) {
+                // if (poly.depth === 0) {
                     pools.push(poly);
                     poly.pool = [];
                     poly.poolsDown = [];
diff --git a/src/mode/cam/driver.js b/src/mode/cam/driver.js
index 0f5932ed..0a7d1716 100644
--- a/src/mode/cam/driver.js
+++ b/src/mode/cam/driver.js
@@ -673,7 +673,6 @@
         let flat = POLY.flatten(offset, [], true);
 
         offset = POLY.setZ(POLY.nest(flat), slice.z);
-        // slice.tops[0].inner = offset;
 
         // inset offset array by 1/2 diameter then by tool overlap %
         slice.tops[0].traces =
@@ -1027,8 +1026,9 @@
                 data.shadow = shadow.clone(true);
                 data.slice.camMode = CPRO.OUTLINE;
                 data.slice.shadow = data.shadow;
+                // data.slice.tops[0].inner = shadow;
                 slices.push(data.slice);
-                onupdate(0.2 + (index/total) * 0.1, "roughing");
+                onupdate(0.2 + (index/total) * 0.1, "outlines");
             }, genso: true });
 
             shellOutline = tshadow;