i have three items to build on.the first is a hollow core door for average size models for use with pins for making stabs,fuselage etc.the other board for scale craft and large gaasrs is a solid core door with a 1/4 sheet of glass on top.this is perfectlly flat.i tack glue parts to this no pins.this is great for zirolli and brian taylor designs.the trhird item is mounted on the solid core door for building wings of almost any shape or size,an ajust-jig.this is monted high enough you can build small parts under it.to bad the ajusto-jig has ceased production probably due to the arf flood.also have the fuselage jigs but they only work well on slab sided designs.