Following the success of his power loom, in 1825 he invented a slotting machine to cut keyways in gears and pulleys to fasten them to their shafts. Previously this was done by hand chipping and filing. The tool was reciprocated vertically, and by adopting Maudslay's slide rest principle, he made the work table with a universal movement, both straight line and rotary so that the sides of complex pieces could be machined. Later he developed the shaping machine, where the cutting tool was reciprocated horizontally over the work, which could be moved in all directions by means of screw-driven slides. Examples of his machine tools, including the oldest existing metal planer, are in the collections of the National Museum of Science and Industry, London.