For the record – I’m using Inkscape v1.0.1, windows 10, Silhouette Studio 4.4.247ss and exporting as DXF 14 using the ROBO option. After the rectangle is added you could add nodes and blow the design up like explained in this post to avoid inaccuracies.

The extension adds a rectangle matching the import size for a cutting mat and media size of 12x12in or 8x12in. I have created an Inkscape extension to easily add this frame. Set the stroke color different from the rest of your design and the frame can easily be deleted in Silhouette Studio without the need for releasing compound paths. But even better – you can define this rectangle so that the original size will be kept – no need of resizing. You can add a rectangle of a known size around your design to define the sizing and then manually resize in Silhouette Studio. The behaviour depend on the save settings for DXF and the document settings in Silhouette Studio. When importing DXF to Silhouette Studio the design is resized to fit a certain size. I have also created an Inkscape extension to easily add this calibration frame.

Now I have figured out how to add a calibration frame around the design to get the correct scaling in Silhouette Studio when importing the DXF file.

These tips will prevent inaccurate results and deformed designs in Silhouette Studio. Previously I have posted some tips on how to best convert from SVG to DXF in Inkscape.

Inkscape dxf scale