Ant colony optimisation is often used to construct solutions to problems for which it has no a-priori knowledge. However, decision makers and designers often have insight and practical experience concerning what constitutes good and acceptable solutions. In this paper we exploit this knowledge by applying a pre-seeding procedure to the initial pheromone structure. Using the real-world RFID antenna design problem, we show that very good solutions can be produced. Moreover, this technique allows fine tuning of the search procedure.