This is my rotor puller
Wheel nut from a truck , same thread as rotor
Smaller nut and bolt , weld smaller nut to truck wheel nut centred
Remove rotor nut and washer from crank , and screw on truck wheel nut to rotor
Screw in bolt (not shown), as i use a universal internal puller with the same thread as smaller nut ( but a bolt will do the job ) to smaller nut till it meets with crankshaft end , then tighten until rotor comes free of crank . If tension getting ridiculous, tap ( dont smash ) bolt with a copper hide mallet ( or hammer ) to asssit removal of rotor .