Just a quick hack to fit the vacuum cleaner to the sander. If you need a different size for your vacuum cleaner, just modify the openscad file and regenerate the stl to fit your needs.
(I printed it vertically, with (snug) supports everywhere, this was easy to remove and very minimal support material needed. If you're unsure about bed adhesion, add a brim.
The author remixed this model.
I added some slots to the smaller part to fit the sander's dust output