Hello from Canada
I have been messing around with locks for 20 years, although I am not a locksmith. I learned master keying by printing and studying sample charts from a master keying software website while in university. I figured out KBA, sub masters, etc by trial and error, mostly.
I have several master keying systems in use, most are just to play around with or personal use, but I have set up and maintain two at church.
I have an eye for detail and a keen interest in keyways, cylinders and blanks. I quite like keys with interesting, almost artistic bittings.
Other areas of interest are light fixtures and classical music.