I have had an X-acto spokeshave-it's a miniature drawknife-that I have been using for about 40 years. I like it better than the razor plane because you pull it towards yourself rather than pushing away. I can control it better. I also draw pencil lines that represent the extreme leading edge or outside edge of the tip. And then be very careful to NEVER cut away any of the pencil line. On tips I finish the plan view first, then sand down to the airfoil, and finally use the spokeshave and sanding blocks to complete the "front view."