Offsets and Filling of Slices

Inner and outer offset of original, blue slice

With the Slice Commander Professional tool, you can create two-dimensional offsets of slices. They can be used, for example, to compensate for expected inaccuracies during production with a machine.

With the option Create Offset in the context menu, you can create either an inner or an outer offset of the slice. It creates a new slice, of which the layers are based on the shape of the original layers, only that they are placed either within or without the original. In a dialog box, you can enter the preferred distance to the original contours, you can edit the roundness for curves of the offset, where it goes around corners of the original, and you can choose between an inner or an outer offset.

This roundness is only relevant when it is necessary that the offset forms a curve, which is the case with outer corners for outer offsets and with corners with a reflex angle for inner offsets (corners projecting inside). If the offset line lies on the inside of the corner of the original, a new corner is created with an identical angle.

The roundness angle represents the maximum angle of two adjacent points of the offset, with the original corner point as apex of the angle. Consequently, the offset curve becomes rounder, when the maximum angle is reduced.

When you click on "OK", a raw offset is created. This consists only of hatches parallel to the original hatches. netfabb also displays lines connecting the end points of the offset hatches with the corner points of the original contour. If there goes around the outside of corners, the additional hatches connecting the open ends (according to your roundness settings) are also added to the offset.

If "Preview Calculations" is ticked, a preview of the finished offset is displayed instead of the raw offset. This offset is finished, if you apply the calculation in the context menu. Calculations are applied automatically when you export the slice (see above). So, you can wait with applying these calculations, which can take some time and disrupt your workflow with complicated slice data, until you export.

Raw offsets

Roundness 1° (left) and 90° (right)

Create Filling

If you choose Create Filling in the context menu, the slice is filled with parallel hatches (straight lines). With some production methods, you can adapt exposure strategy during production without changing the actual shape of a part.

In a dialog box, you can insert the distance of hatches. To know the correct distance, it is important to know the specifications of your machine.

The angle determines the direction of the hatches, referring to the X-axis with a clockwise rotation. Thus, if you leave 0°, the hatches will be inserted along the X-axis. If you insert 90°, they will run along the Y-axis.

A round contour with filling: first, a filling with an angle of 0°, then with an angle of 45°

The Rotation per Layer can be used to give the hatches of different layers different directions. In that case, only the the first layer of hatches has the angle specified above. After that, the angle changes with every layer (going upwards) by the degree you enter here

Two consecutive layers of the same slice file with a rotation of 20° per layer

If you increase the number for Filling only each ... layer, not every layer of the original contour will be filled. If you insert 2, for example, there will be one filling layer for every second contour layer.

Note: The Rotation per Layer refers to the filling layers, independently from the number of contour layers in between.

The Translation per Layer determines, if and how far the hatches are shifted with each layer. If you insert zero, the hatches of the slice layers will be on top of each other. If you insert 1.0, the hatch lines are upwards shifted by one mm with each layer, going from the top to the bottom layer.

With the rotation and the translation per layer, you can avoid that the filling hatches are exactly on top of each other. With some production methods, this could lead to lower part quality and instability.

The filling is inserted as new slice file when you click on "OK" . It is treated as independent object in the Slice Commander in the project tree.

Here, the filling is moved out of the contour as an independent slice

Tutorials

Netfabb Studio Tutorial - Create Hollow Part With Slices