Efficient sealing of the gaps within positive displacement vacuum pumps, such as the screw spindle vacuum pump, contributes greatly to their performance characteristics. To address this, a novel approach using structured surfaces on the rotor tip is studied to reduce gap flows at high gas rarefaction. While previous studies have analysed the effects of these structures through simulations, this paper presents the setup to demonstrate this effect experimentally. For this, the Poiseuille flow through a plane parallel gap is examined. The experimental boundary conditions for manufacturing the workpiece as well as the geometric measurement of the surface structure are explained. The experimental setup for the plane parallel gap flow is described and the impact of different variables is investigated. Utilising smooth surfaces only, for now, the rarefied Poiseuille flow test rig is then validated by comparison to an analytical model.