Someone Of His Calibre

The quality of character or size of a gun barrel,
maybe there the same or at least both integral;
someone laughed when I said 'OD' instead of 'ID,'
but then plumbers don't really inspire a sense of mystery.

I was walking on an estate when I saw Artisan Crescent,
an immediate vision of tradesmen holding spanners meant,
that I'm not a snob and they earn more money than we do,
however, I'm not the gas man, no intention of dressing in blue.

Look at the picture by Mr. Da Vinci above - what a cv -
painter, sculptor, inventor - like him, wouldn't we like to be,
to have something of his calibre would be a bonus,
instead of lingering in our cosy level, let's be famous.

I'm a backroom boy, don't want the spotlight - you're wrong,
now is your chance, never again will it come along.

Note: 'OD' = outside diameter, 'ID' = inside diameter.
          The difference is the thickness of the metal.