Flatterer

Flatterer turns a 3D model in Blender into a set of shapes suitable for laser cutting. It’s aimed at easily exporting boxes, enclosures, and other made-for-laser-cutting designs to SVG.

Get Flatterer (flatterer-xxx.zip)

The add-on comes with an blend file with an example box (a slightly simpler box than the one shown at the top) to illustrate how the add-on is supposed to be used.

Installation

1. Download the Flatterer add-on. It’ll be named something like flatterer-v1.5.0.zip in the “Packages” section.
2. Start Blender and go to Edit ➜ Preferences ➜ Add-ons.
3. Press Install… and select the ZIP file you just downloaded.
4. Go through the settings (see below) and configure the add-on defaults.

Usage

1. Add a plane and shape it.
2. Press the Add Solidify Modifier (available in Object mode) to add some thickness.
3. Press the Flatten to SVG Outline button to export to an SVG file.

3D Viewport Panel

The add-on adds a panel to the 3D Viewport side-bar, in the Export tab.

Scene Settings

These settings are stored on the Scene; in other words, they can be adjusted for each blend file you’re working on. The default values are set in the add-on preferences.

Laser Width

The width of the cut the laser leaves behind, also known as tool size in CAD/CAM software. Each exported edge is moved outward by half this width, such that the final shape matches the Blender design exactly.

Material Width

The shape packing algorithm won’t go wider than this width. Set it to whatever the maximum width is you want to use, depending on the material you’re cutting and the margins you want to keep.

Material Length

Set this to the length of the cuttable material. Flatterer will output one or more pages of width × length in size.

Material Thickness

The thickness of the material you’ll be cutting. This is used by the Solidify modifier (see below).

Margin

The minimum distance between the edge of the material and cut-out parts.

Shape Padding

The shape packing algorithm will keep this much space between the parts.

Setup Scene for mm

Configure the Scene to use 1 unit = 1 mm. This configuration is assumed by the exporter; it doesn’t actually take the Scene scale into account. This operator also updates the 3D Viewport grid size to match.

Packing Options

Sorting

The packing algorithm tries to fit each shape as well as possible. It does this basically shape by shape, and thus the order in which the shapes are packed has an impact on the result. This option allows you to choose this sorting. The choices are:

• Do not sort. Not sure what the use is, but you never know.
• Sort by descending area.
• Sort by descending perimeter. This was the old hard-coded behaviour, and still is the default.
• Sort by difference of rectangle sides.
• Sort by shortest side.
• Sort by longest side.
• Sort by ration between sides.

Rotation

The packing algorithm can rotate each shape by 90° to see if that works better. If you don’t want this, you can now turn it off.

Reduce Waste (removed in version 1.3)

This option has been removed in version 1.3. It got in the way of the multi-page export option, and didn’t turn out to be as practically useful as I hoped it would be.

Object Options

These options are only available when a mesh object is selected.

Exclude from Export

Prevents this object from getting exported. Enable this on helper objects if you just want to do “Select All, Flatten to SVG Outline”.

Add Solidify Modifier

Add a Solidify modifier to the active object, with a driver on its thickness so that it follows the scene’s Material Thickness setting. Only available in Object mode.

Align to Local Axis

Analyses the mesh and rotates it to align its local axes with the orientation of the mesh. The object is counter-rotated to ensure the mesh doesn’t visually move.

Edge Options

These options are only available when Blender is in mesh edit mode.

Kerf Compensation on/off

Edges that are exported for cutting will be “kerf-compensated”. This means that they are moved slightly to compensate for the width of the laser beam. Here you can disable this, for those edges where you don’t want this behaviour.

Engrave on/off

Use this to mark edges for engraving.

Select Export Edges

Select the mesh edges that will be exported. This doesn’t do anything else; it’s just a helpful tool if you want to see what’ll get exported and what won’t.

Separate Mesh into Faces

Split up the mesh into multiple objects. All faces that have the same orientation will be assigned to the same object. This is typically used to split up a box into its separate sides.

Extrude Finger

Select edges and press Extrude Finger to extrude them away from their faces. The extrusion will use the material thickness. This is used for finger connections to connect parts.

The Button

Flatten to SVG Outline

Takes the selected mesh objects, applies kerf compensation, packs the resulting shapes, and writes them to an SVG file.

The popup where you name the SVG file also has a side-panel in which you can enable the shape table.

Limitations

There are some limitations that I want to lift at some point, but which at the moment of writing are still in there:

• Scene scale settings are ignored, hence the Setup Scene operator.
• The mesh must be planar (as in, flat) and aligned to local axes. It doesn’t matter whether it aligns with the XY, YZ, or XZ plane, but it has to align with one of them.