EDIT: UPDATE BELOW

I liked the idea of a multicultural fortress so when a few human bards petitioned to become citizens I allowed it.

Couldn't believe my luck when one turned out to be a high master clothier, and another a master armorsmith. Queued up the orders for steel shirts and helms to take advantage of it.

The human armorer got right to work churning out armour pieces. Three or four in, he produced his first masterpiece helm, prompting an announcement. Urist McHuman, metalsmith, has produced a masterful LARGE steel helm.

Even using the details screen to specify dwarf-sized armour didn't seem to change this behaviour. Every piece came out large, meaning it all had to be melted and redone.

Whether this is a bug, or intentional behaviour I don't know. Has anyone else experienced this or anything similar? Or found a workaround for it?

My only consistent source of steel was from goblinite, making it an especially valuable resource for me.

UPDATE: After a bit more testing with my human clothier, I ordered a pair of trousers sized for elves and allowed only the human clothier to make them. They came out suitable for dwarves, but in the description of the item specified that they were sized for elves.

This makes me think that the setting for dwarf-sized is programmed as a default setting, rather than an actual specific size. This leads to clothiers/armorsmiths making items to their own default size (large in the case of humans).

TLDR: To get human armorers or clothiers to make items suitable for your dwarves to wear, tell them to make elf-sized items.