RE: help on balancing low wing planes
The idea of hanging is the plane will slide on the line to show the CG. The hook doesn't always allow this so a pulley should be used instead of the hook. A plumb bob is hung from the center of where the string is attached to the ceiling and will show the CG. In my old shop I had a small block and tackle for hang balancing. When done correctly it works great. You can balance for CG and lateral at the same time. No, the plane doesn't have to be level to start balancing. If the plane is out of balance it will never be level. I haven't bothered with it in my new shop, I have been using a CG machine. I do hang them for lateral balancing once in a while.