90 degrees is a whole lot more than I can do with the inner elbow of my masked rider suit. ThanksIs a strip of foam with 6 more bands glued, then covered with pva (6 hands) sanded with fine 200 paper and sprayed with plasti spray. Then primer and paint and finisher. The foam actually bends without cracking, but the arm can bend just 90 degrees due to hinges.
Hope this can help you!