Marks & Lines - navigating to the 'where to begin' the cut, carve & hollow. The following images show the stages of creation at the start of the carving & hollowing in the NPC-BS bench.
The above images show the basic block shapes. The long bridge cut has already been placed on the leading edge underside.
The 2nd image shows the line marking & direction flow - a kind of contour mapping of where to cut.
The seating boards are set on corrugated cardboard membranes on top the base blocks to give a small working gap space whilst working on the side profiling.
The oak seating boards will be set finally on to 1.5 mm stainless steel shim plates between concrete and oak to maintain neutrality between the tanic acid of the oak and alkaline quality of the concrete. You can see the prep shims laying on the bench in the 1st image.
Once marked up, carving & hollow form shaping can begin.