A real workshop, armed with modern tools, is needed to manufacture anything that looks more like a laser gun than a stone axe (to do the latter, an Extractor is enough, or sometimes even some unused space in the stores). Maximum capacity is 30 runts.
There is, however, a limit to what manual labour is capable of, and constructing more than 1 Workshop per Hideout would be pointless. To increase our industrial power, we need to devise more advanced forms of manufacturing.