Ben Williams

I've come across a rosewood ended english system lachenal i'd like to restore for experience. There are no major problems I can see so far (valves, a few bellows leaks, the odd split chamber wall). However, the screws on the thumbstraps, and one on the endpiece have rusted so badly, and have subsequently been damaged by screwdrivers attempting to remove them, that I can't see under the endpieces. What's the best way to get the old screws out without creating more damage?

I have a Lachenal anglo circa 1900-1910 with radial reed chambers. A reed went flat on the draw. On inspection, a couple of the chamber walls have very small splits at the base, thus allowing excess airflow. An accordian maker/repairer has recommended sealing these gaps using beeswax. Any other ideas or advice?