One of the more interesting and creative uses of the lathe is to use it for 'spinning' small objects from sheets of copper, brass, pewter, lead -or even thin steel. Spinning is a very old production process - and even today craftsmen in Sheffield and other locations turn out pewter tankards and other artefacts on heavily-built but basic plain-turning lathes. The operation consists of fitting a finely-finished steel "Former" to the spindle nose (the Former can be in wood for short production runs which require only a reasonable surface finish) and then clamping a sheet of suitably thin and soft metal between it and a rotating centre. By dint of strength, dexterity, a keen eye, fine feel - and a seven-year apprenticeship - the spinning metal is spread over the form using various tools levered against one or more fulcrum points.
Spinning is a 'black art' and, although simple jobs are well within the capabilities of an amateur turner, to successfully turn out larger and more complex shapes does require considerable knowledge and experience..
Beyond spinning and the weight of work it can handle, is a process called "forming", where the strength of the lathe, its slides and cutter holders are fully tested by having to turn metal to shape by forcing into it a suitably-shaped forming (cutting) tool. Although this sort of work can often be done easily enough on a conventional capstan lathe, the forming lathe was designed to be a simple and economical alternative - cheap to buy, easy to set up, simple to operate by unskilled labour and reliable - the only critical operation in the process is the design and making of the forming tool itself.
The Meriden Company of Connecticut, USA, specialised in making the sort of lathes used for these processes and, besides building forming lathes, described themselves as: "Die makers and builders of special machinery, spinning lathes, buffing heads, tools and fixtures." They claimed to have been the first firm in the USA to market a dedicated forming lathe -which was probably true, most forming being done at the time on obsolete lathes which were beyond use for accurate turning between centres. The Meriden lathe enjoyed the advantage of an intercoupling of forming-slide action and work-holding collet release; as the job was completed, and the tool withdrawn, the collet opened and - if bar feed was fitted - fresh material appeared for the tireless piece-rate operator to apply his strength to.
The Meriden range of lathes at the end of the 19th and beginning of the 20th centuries was limited to a handful of strongly-built machines which were dedicated to production work. The two basic models in the range, with centre heights of 6 and 9 inches, were supplied with a plain, lever-action cross (forming) slide and were designed for manufacturing: "plumbers' goods for turning handles, cocks, etc.; to manufacturers of valves, injectors, etc., for turning packing nuts, glands, bonnets, caps, nipples, coupling nuts, etc., manufacturers of casket hardware and silver-plated ware, for turning casket handle tips, pepper, salt and mustard tops, tips for covers of hollow ware, etc., and has also been used to good advantage by manufacturers of wooden faucets, handles, etc., and by manufacturers of malleable iron fittings."
The better-equipped models, available in 12, 15 and 18-inch swings, were described as "Improved Forming Lathes" and featured a more complex and versatile forming slide - a description of which can be found below.
As an example of what could be achieved, the "Improved Lathes" were claimed to be capable of turning out, depending upon the thickness of the brass used, between 500 and 700 door handles, 500 to 2500 valve bonnets or 1000 to 1200 roses in an arm-aching, ten-hour shift …