D-limonene can be used for dissolving HIPS support material. Place the printed HIPS object and a second, non-soluble material in a container of limonene and watch the HIPS material slowly dissolve. With HIPS as a support material, you can 3D print objects with hollow or open spaces in this way. The can of D-limonene contains 1 litre.
Attention: read the safety instructions on the packaging before use.