If you breaking 0012 ribs, consider using slightly heavier balsa or just doing a 1/64" ply lamination prior to cutting them. I've found gorilla glue to be outstanding for this sort of rib lamination. After setting for about 90 minutes its hard enough to start shooting through a router/sanders/bandsaw. I do this all the time with center section ribs.

I've also had success using gorilla glue to fab 3/32 "balsa plywood" ribs out of 3 layers of 1/32 balsa. With one of the veneers oriented vertical, any cracking tendency is virtually eliminated.