Positron moderators made with stacks of electro-polished tungsten meshes have been tested. The wires of the meshes were thinned to about 10 mum in diameter by an electro-polishing treatment. The moderation efficiency was measured to be 7.5 x 10(-4) for 12 overlapping meshes. (C) 2002 Elsevier Science B.V. All rights reserved.