Selecting a metal lathe requires matching the machine's capacity to your production needs. Key metrics include the Swing Over Bed (maximum diameter of the workpiece) and Distance Between Centers (maximum length). For industrial B2B applications, prioritize lathes with induction-hardened bed ways to ensure long-term precision and wear resistance. Additionally, verify the spindle bore diameter to ensure it can accommodate the bar stock sizes you intend to process, and look for variable speed controls or a quick-change gearbox to enhance operational efficiency across different materials like aluminum, steel, or titanium.