I have just had this issue. I could only get to about 50 degrees also. Following advice from Framer Joe, I fully undid the hinge points and verified they would not move far enough. I dropped a little oil onto the hinge points. The front hinge nearest the locking handle was the only point with the problem.
I could not believe that this simple remedy would fix the issue. I also resolved my mis-aligned saw blade that was running about 0.2mm out of true at the same time as I refitted the hinges (there is a chunk of adjustment there). Stunned that a little oil could fix this. Surprised Pikachu face when it worked out.
