Mechanical Polybius Square

A Polybius square with 2 "arms intersecting at the correct letter per input.

Assembly: Place the Mark2 lower onto the lower set of holes on the Mark2 square. The pegs should face down. Then put the Mark2 upper onto the upper set of holes of the Mark 2 square. The pegs should face down. Then place the Mark 2 frame on top of the assembly, be careful to have the right rotation(each arm should have the same clearance.), and apply a firm force to close the two together.

Note: The arms have a pretty loose fit, but the frame has a tight fit. Adjust it so it fits firmly.