Sewing Machine Hook Timing | Rotary Hook Sewing Machine Timing

The instructions below are intended for setting the time on sewing machine models, it's a whole series of vintage Pfaff sewing machines, I have to list them all: Pfaff 1222, Pfaff 1221, Pfaff 1214, Pfaff 1213, Pfaff 1212, Pfaff 1211, Pfaff 1199, Pfaff 1197, Pfaff 1196... 
Likewise, this instruction can be applied to most sewing machines that have a rotating hook, everything is very similar, the specified special tools are not mandatory and especially necessary, the specified measures are also not "sacred letter" and you can slightly deviate from them.