A cold saw module may be a rail saw module that includes a cold saw configured to cut a railway rail along a cutting path, a rail alignment clamp configured to grip the railway rail near the cutting path, a feed actuator to drive the cold saw along the cutting path, and a module coupling element configured to selectively couple to a mating module coupling element of an articulated arm and/or a tool adapter. Cold saw modules may be used to cut metal workpieces such as a railway rail. Cutting a railway rail may include positioning the cold saw module at a cutting site along the railway rail installed in a railway, clamping the cold saw module to the railway rail, and cutting the railway rail at the cutting site with the cold saw module while the cold saw module is clamped to the cutting site.