A low-cost multipurpose neutron scattering beamline was constructed and commissioned at the W3 beam port of the Tsing Hua Open-Pool Reactor, National Tsing Hua University. This beamline is capable of performing neutron powder diffraction, neutron reflectivity, and neutron depolarization measurements. In order to reduce the cost, a non-rotatable monochromator shielding tank filled with boric acid was built. This shielding tank was designed with three separate pre-selected beam ports for three different neutron wavelengths. This beamline was tested with NiFe foils and a Ni/Ti multilayer.