Idiom
be an professional to fingertipsbe an [artist/patriot/professional/etc.] to (your) fingertips
if you say that someone is an artist, patriot, professional etc. to their fingertips, you mean that they behave in a way which is completely typical of such a person, and it is the most important part of their character.Mark, a professional to his fingertips, insisted that we should make proper joints, not simply nail the pieces of wood together.