Perhaps there are differences between the various (country) navies and also in time period. Pyrard de Laval (1575-1652) points out some, distinguishing determined habits aboard practiced by either Portuguese, Dutch, English French.
May also the logic of terminology be considered, aggravated by my poor english and translation difficulties.
Senior sailors and (cabin) boys would be a distinct thing, respectively in what touches their recruiting, capacities, attributions and behavior from command towards each of them.
Laval makers a thorough description of the navigation between Portugal and India, emphasizing distinctions of crew members in the diverse type of embarkations, namely carracks (Naus) for the (so called) India career, all built in Lisbon, destined to bring back spices (generally called pepper), or the galleons ready for combat, to transport big shots or other express purposes, these being also built in India ship yards and elsewhere. He states that such carracks reached much over 1000 tons, being therefore the largest ships out there, not able to navigate on less than ten braces depth. Concerning personnel, he describes a remarkable distinction between the well considered sailors of such large merchandise carracks and mid size ships, where sailors were of lower profile, those, yes (your’e right here) were caught by force … even superior rank, assuming that those ships do not come back. And if ever they return, their crew men might get a post in large ships, but no so high as in the galleons they have served; from what comes that is a higher honor be a sailor in a large carrack than counter master in a galleon.
Concerning knives aboard, i believe these were decidedly sailors gear, but naturally not that of boys, be them grumetes (aspiring to sailors) or pages which, after all, counted for a significant number of the garrison aboard. Laval mentions more than one boy per sailor; narrations from the Pedro Alvares Cabral period (1500’s) describe these boys with ages from 12, receiving a symbolic salary and, in both descriptions, performing the simplest jobs, like wetting the decks (would could not get too dry, risking the whole boat to crack), screaming the hours (live clocks) and other kind of “public” attentions, besides serving their master sailors in all services aboard.
… But i am digressing here
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