Flatterer

5 min read

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.

Features
Automatically pack SVG shapes ✔️
Engrave marked edges ✔️
Expand cuts to correct for laser width (kerf compensation) ✔️
Aids in setting up scene for millimeter precision ✔️
Aids in adding solidify modifier for material thickness ✔️
Slicing of 3D models 1

Installation

  1. Download the Flatterer add-on. It’ll be named something like flatterer-v1.3.0.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

2D design of a laser-cuttable part.
2D design of a laser-cuttable part.
  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.

3D Viewport Panel with options and operators.
3D Viewport Panel with options and operators.

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:
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.

Edge Options

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

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.
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.

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:


  1. Flatterer doesn’t slice 3D shapes. Instead, it requires that you yourself already work with flat surfaces. For slicing, use BlenderCAM↩︎