Small Pd clusters were fabricated by tip-induced metal deposition and patterned on a Au(111) electrode with the help of a scanning tunnelling microscope. An array of 400 clusters, which had an average height of 0.4 nm, was generated at a rate of 80 clusters per second. By changing the tip approach the cluster height was varied between 0.2 and 1.0 nm. The implications of this technique for studying size effects in electrocatalysis are addressed briefly.