One should not confuse a tinkerer and a tinker! A tinkerer is a person who tinkers with machinery, modifies products and is the heart and sole of inventors and innovators. However, a tinker is someone who fixes household items with tin. These wondering tin smiths became a vagabond of sorts in the early industrial age and are associated with a negative connotation. Tinkerers on the other hand are highly regarded in society, think of Thomas Edison.
One aspect of being a successful machinist is the ability to tinker, in the tinkerer sense. Only by attempting new methods, tweaking old methods and testing these thoughts can a machinist improve upon his work and craft. While an endearing image of a tinkerer may be an old man farting around with clocks, the truth is that without that tinkering spirit innovation would come to a standstill. So tinker away, take things apart and see how they run and if they can be improved, for if it wasn't for this kind of innovator we wouldn't have light bulbs or artificial hearts!