diff --git a/src/sliceActions/applyPrecision.js b/src/sliceActions/applyPrecision.js
index 8fa3187..d7f8089 100644
--- a/src/sliceActions/applyPrecision.js
+++ b/src/sliceActions/applyPrecision.js
@@ -2,10 +2,11 @@ import { PRECISION } from '../constants.js'
 
 export default function applyPrecision(shapes) {
   for (let i = 0; i < shapes.length; i ++) {
-    const { closedShapes, openShapes } = shapes[i];
+    const { fillShapes, lineShapesOpen, lineShapesClosed } = shapes[i];
 
-    scaleUpShape(closedShapes);
-    scaleUpShape(openShapes);
+    scaleUpShape(fillShapes);
+    scaleUpShape(lineShapesOpen);
+    scaleUpShape(lineShapesClosed);
   }
 }
 
diff --git a/src/sliceActions/generateInfills.js b/src/sliceActions/generateInfills.js
index 1b87787..3ddfa56 100644
--- a/src/sliceActions/generateInfills.js
+++ b/src/sliceActions/generateInfills.js
@@ -34,7 +34,7 @@ export default function generateInfills(slices, settings) {
     for (let i = 0; i < slice.parts.length; i ++) {
       const part = slice.parts[i];
 
-      if (!part.shape.closed) continue;
+      if (!part.closed) continue;
 
       const innerShell = part.shell[part.shell.length - 1];
 
diff --git a/src/sliceActions/generateInnerLines.js b/src/sliceActions/generateInnerLines.js
index c2767c7..0c97a5d 100644
--- a/src/sliceActions/generateInnerLines.js
+++ b/src/sliceActions/generateInnerLines.js
@@ -27,7 +27,7 @@ export default function generateInnerLines(slices, settings) {
     for (let i = 0; i < slice.parts.length; i ++) {
       const part = slice.parts[i];
 
-      if (!part.shape.closed) continue;
+      if (!part.closed) continue;
 
       const outerLine = part.shape.offset(-nozzleRadius, offsetOptions);
 
diff --git a/src/sliceActions/generateOutlines.js b/src/sliceActions/generateOutlines.js
index b3609db..036b519 100644
--- a/src/sliceActions/generateOutlines.js
+++ b/src/sliceActions/generateOutlines.js
@@ -5,7 +5,7 @@ export default function calculateOutlines(slices, settings) {
     const slice = slices[layer];
 
     slice.outline = slice.parts.reduce((shape, part) => {
-      if (part.shape.closed) {
+      if (part.closed) {
         const [outerLine] = part.shell;
         shape.join(outerLine);
       }
diff --git a/src/sliceActions/helpers/Slice.js b/src/sliceActions/helpers/Slice.js
index b02c6ab..10b22fe 100644
--- a/src/sliceActions/helpers/Slice.js
+++ b/src/sliceActions/helpers/Slice.js
@@ -4,10 +4,10 @@ export default class {
   constructor() {
     this.parts = [];
   }
-  add(shape) {
-    const part = { shape };
+  add(shape, closed) {
+    const part = { shape, closed };
 
-    if (shape.closed) {
+    if (closed) {
       part.shell = [];
       part.innerFill = new Shape([], false);
       part.outerFill = new Shape([], false);
diff --git a/src/sliceActions/intersectionsToShapes.js b/src/sliceActions/intersectionsToShapes.js
index c46fc05..f416f79 100644
--- a/src/sliceActions/intersectionsToShapes.js
+++ b/src/sliceActions/intersectionsToShapes.js
@@ -10,8 +10,9 @@ export default function intersectionsToShapes(layerIntersectionIndexes, layerInt
 
     if (intersectionIndexes.length === 0) continue;
 
-    const closedShapes = [];
-    const openShapes = [];
+    const fillShapes = [];
+    const lineShapesOpen = [];
+    const lineShapesClosed = [];
     for (let i = 0; i < intersectionIndexes.length; i ++) {
       let index = intersectionIndexes[i];
 
@@ -107,14 +108,17 @@ export default function intersectionsToShapes(layerIntersectionIndexes, layerInt
       }
 
       if (openGeometry) {
-        if (!openShape) shape.push(shape[0].clone());
-        openShapes.push(shape);
+        if (openShape) {
+          lineShapesOpen.push(shape);
+        } else {
+          lineShapesClosed.push(shape);          
+        }
       } else {
-        closedShapes.push(shape);
+        fillShapes.push(shape);
       }
     }
 
-    layers.push({ closedShapes, openShapes });
+    layers.push({ fillShapes, lineShapesOpen, lineShapesClosed });
   }
 
   return layers;
diff --git a/src/sliceActions/optimizePaths.js b/src/sliceActions/optimizePaths.js
index dd249a2..18043ef 100644
--- a/src/sliceActions/optimizePaths.js
+++ b/src/sliceActions/optimizePaths.js
@@ -17,7 +17,7 @@ export default function optimizePaths(slices, settings) {
     for (let i = 0; i < slice.parts.length; i ++) {
       const part = slice.parts[i];
 
-      const shape = part.shape.closed ? part.shell[0] : part.shape;
+      const shape = part.closed ? part.shell[0] : part.shape;
       const bounds = shape.shapeBounds();
 
       boundingBoxes.set(part, bounds);
@@ -47,7 +47,7 @@ export default function optimizePaths(slices, settings) {
       const [part] = slice.parts.splice(closestPart, 1);
       parts.push(part);
 
-      if (part.shape.closed) {
+      if (part.closed) {
         for (let i = 0; i < part.shell.length; i ++) {
           const shell = part.shell[i];
 
diff --git a/src/sliceActions/removePrecision.js b/src/sliceActions/removePrecision.js
index ccc8466..2ecd8df 100644
--- a/src/sliceActions/removePrecision.js
+++ b/src/sliceActions/removePrecision.js
@@ -9,7 +9,7 @@ export default function removePrecision(slices) {
     for (let i = 0; i < slice.parts.length; i ++) {
       const part = slice.parts[i];
 
-      if (part.shape.closed) {
+      if (part.closed) {
         for (let i = 0; i < part.shell.length; i ++) {
           const innerLine = part.shell[i];
           innerLine.scaleDown(inversePrecision);
diff --git a/src/sliceActions/shapesToSlices.js b/src/sliceActions/shapesToSlices.js
index ea0e5be..2d0fe94 100644
--- a/src/sliceActions/shapesToSlices.js
+++ b/src/sliceActions/shapesToSlices.js
@@ -9,15 +9,18 @@ export default function shapesToSlices(shapes, settings) {
   const sliceLayers = [];
 
   for (let layer = 0; layer < shapes.length; layer ++) {
-    let { closedShapes, openShapes } = shapes[layer];
+    let { fillShapes, lineShapesOpen, lineShapesClosed } = shapes[layer];
 
-    closedShapes = new Shape(closedShapes, true, true, true, true)
+    fillShapes = new Shape(fillShapes, true, true, true, true)
       .fixOrientation()
       .simplify('pftNonZero')
       .clean(cleanDelta)
       .seperateShapes();
 
-    openShapes = new Shape(openShapes, false, true, true, true);
+    lineShapesClosed = new Shape(lineShapesClosed, true, true, true, true)
+      .clean(cleanDelta);
+
+    lineShapesOpen = new Shape(lineShapesOpen, false, true, true, true);
     //   .clean(cleanDelta);
     // TODO
     // Cleaning is actually wanted here but there is a bug in the clean function
@@ -25,17 +28,24 @@ export default function shapesToSlices(shapes, settings) {
 
     const slice = new Slice();
 
-    for (let i = 0; i < closedShapes.length; i ++) {
-      const closedShape = closedShapes[i];
-      slice.add(closedShape);
+    for (let i = 0; i < fillShapes.length; i ++) {
+      const fillShape = fillShapes[i];
+      slice.add(fillShape, true);
 
-      // if (openShapes.path.length > 0) {
-      //   openShapes = openShapes.difference(closedShape);
+      // if (lineShapesClosed.paths.length > 0) {
+      //   lineShapesClosed = lineShapesClosed.difference(closedShape);
+      // }
+      // if (lineShapesOpen.paths.length > 0) {
+      //   lineShapesOpen = lineShapesOpen.difference(closedShape);
       // }
     }
 
-    if (openShapes.paths.length > 0) {
-      slice.add(openShapes);
+    if (lineShapesClosed.paths.length > 0) {
+      slice.add(lineShapesClosed, false);
+    }
+
+    if (lineShapesOpen.paths.length > 0) {
+      slice.add(lineShapesOpen, false);
     }
 
     sliceLayers.push(slice);
diff --git a/src/sliceActions/slicesToGCode.js b/src/sliceActions/slicesToGCode.js
index b14e9d4..fd38039 100644
--- a/src/sliceActions/slicesToGCode.js
+++ b/src/sliceActions/slicesToGCode.js
@@ -37,7 +37,7 @@ export default function slicesToGCode(slices, settings) {
       profiles[profileType] = {
         ...defaultProfile,
         lineProfile: isFirstLayer ? settings.firstLayer : settings[profileType]
-      }
+      };
       return profiles;
     }, {});
 
@@ -48,7 +48,7 @@ export default function slicesToGCode(slices, settings) {
     for (let i = 0; i < slice.parts.length; i ++) {
       const part = slice.parts[i];
 
-      if (part.shape.closed) {
+      if (part.closed) {
         for (let i = 0; i < part.shell.length; i ++) {
           const shell = part.shell[i];
           const isOuterShell = i === 0;