Walter's solution to this problem was to build a whole new linkage system for the thumb valve. As I recall it had three pivot points. One was to make the reversal and the others were to reduce the amount of movement needed on the thumb. Hey, it's been thirty years and I only saw it once. Wish I could be of more help. Wilbert in SC _______________________________________________ post: horn@music.memphis.edu unsubscribe or set options at http://music2.memphis.edu/mailman/options/horn/archive%40jab.org