It has 4 different versions: Singer 111W152 is a single needle, lockstitch, compound feed machine with a vertical axis hook, and alternating pressers have 3/8 lift. It has a safety clutch which prevents the hook from being damaged or getting out of time due to accidental strain.
The maximum stitch length is 5 to the inch. The machine is used for stitching light leather work such as leather gloves. Singer 111W153 is similar to Singer 111W152 but is used for heavy work, such as automobile and furniture upholstery, tents, awnings and leather coats. Singer 111W154 is similar to Singer 111W152 but its alternating pressers have a lift of 1/2 inch and the machine is designed for stitching upholstery work, leather coats, buff wheels and binding heavy felt padding. Singer 111W155 is similar to Singer 111W154 except that its maximum stitch length is 3-1/2 to the inch and it has an adjustable lifting eccentric to instantly set the alternating pressers to the minimum amount of lift required for the work to be sewn.
This machine and Singer 221W industrial sewing machine and subsequent Juki LU-562 & Juki LU-563 have been stop production very long time ago. If you need spare hook, please contact cowboysew.com. and if you need a modern machine as replacement, you can consider COWBOY #74400 &74420. COWBOY #74400 &74420 is fine clone of Mitsubishi LU2-4400-BOB & LU2-4420-BOB, widely used in medium weight sewing applications, like furniture upholstery, automobile upholstery, sofa, jumping castles (bouncy castles), car seats, safety belts, lifting slings, container bags, boat sails, military parachutes, tents, awnings, lorry curtain sidings, handbags, outdoor wear, camping goods and general canvas work etc.