Hi. Thanks again for all your ideas and for correcting my misunderstanding re Cherub t foils. I had a chat with John Pierce yesterday who was very helpful. The Vortex has aluminium foils chord length c.180mm..heavy but totally bombproof and as a first effort to see whether they are going to work, Im going to have a section of foil TIG welded to the base of the rudder. Once again thanks.Will let you know if there are any amusing consequences.