I removed a bit more of the aft edge of the HS to allow for paint and smoother elevator travel. Before doing so, I could feel a little binding around 12 degrees. I was surprised how much I needed to remove. A bti of history on the Lightning tail evolution explains why.
During high speed flying, a completed Lightning experienced flutter in the tail that was traced back to the aft edge of the HS being too thin. This only affected 6 (I think) kits per Nick, the designer and mine is not one of them. The fix for this is to add several layers of carbon fiber to the area which is now being done during kit manufacturing. So, because this area has been beefed up and is thicker, I needed to sand off some of the bottom length (not thickness) and bevel the inside lower aft edge to provide clearance for the elevator to travel smoothly. Using the belt sander on the first few passes made this go pretty quickly.
