If the bottom long axis rails are on the same surface as the material being cut, the RGS unit is rated for 2-1/4 material (9/4 boards) You can increase this capacity by raising the bottom long axis rails relative to the support surface. For instance, making the banding boards from 2x6 material rather than 2x4 material will raise that capacity by 1-1/2 inches, giving you a 3-1/2 to 3-3/4 inch thickness capacity. Alternatively, the table can be designed with a lift system that the long axis rails are affixed to such that the rails can be lifted upwards and pinned in various positions. If need be you can also construct pylons for the RGS to rest upon in the case of needing to plane out projects that are already installed or in place such as a bar top. Simply create pylons down to the flooring and build the RGS unit above or around the item being planed. This could include large stumps or burls.