4. Process your mold. If you decided to print the combo version, manually split the mold into inner and outer pieces, cleaning off as much support material as possible. Depending on your printer’s abilities and settings, your print(s) will have ridges that will make it hard to remove your pot from the mold. You could sand (and sand and sand and sand) the surface, but it’s much easier to use a coating like XTC-3D to smooth the surfaces that will touch concrete. Just follow the directions and wipe it on. Once it’s dry, coat the areas you’ve smoothed with a layer of petroleum jelly, which will help the mold slide off after the concrete has cured.