Man has always tried to find ways of making manual tasks easier and the businessman methods to reduce manpower, speed production and lower operating costs. A good illustration of this was the manufacture of rifle butts. Hand held firearms have existed since the Middle Ages and virtually all these weapons incorporated a hand fashioned wooden butt. Making rifle butts was a highly skilled and time-consuming occupation and in time highly protective guilds were formed and prices kept at a high level.
This was just the sort of situation where a machine solution would be welcomed by firearm manufacturers, and in 1820, an Englishman, Thomas Blanchard designed a ‘reproducing lathe’. Blanchard’s lathe was capable of making two rifle butts an hour and it was not long before he had built one capable of producing ten or twelve in an hour. He went on to devise other reproducing lathes to manufacture shoe lasts and axe handles.
There are two basic types of what Blanchard called reproducing lathes, the first type mechanically follows a template or three dimensional pattern and is generally known as a copy or copying lathe. The second type are called automatics and contain a series of profiled blades set in a revolving drum, both have their own advantages. A copy lathe is capable of producing eccentric shapes such as those that Thomas Blanchard was interested in while an automatic lathe was primarily used for turning spindle work. A well-adjusted and sharpened automatic lathe is capable of tuning very complex and highly detailed shapes extremely quickly.
William Fell of Cumbria developed lathes of both types and by 1880 was exporting them to Russia, Japan and North America. Fell lathes are still widely used today. A German firm called Kirchner from Leipzig manufactured a large variety of automatic and copy lathes. In a catalogue C.1925 these included lathes for producing Oval picture frames, wooden shoe heals, cabriol chair legs and barley sugar twists.
It is interesting to note the impact that mechanization has had on the chair making area of High Wycombe over the last seventy years. In my own village of Holmer Green, close to the town, many local men were still using pole lathes to turn chair legs well into last century. One enterprising man, Bert Saunders decided to mechanized and invested in a semi automatic lathe to increase production. This machine worked relentlessly for many decades until the 1970s.
The heart of the lathe was a large steal horizontal drum that acted as a cutter-block, rather as in a spindle moulder. A series of paired profiled cutters, called knives in the trade, were secured along its length, ‘setting up’ required great skill as did the profiling and sharpening of the cutters themselves. The drum revolved at great speed while the wood to be turned was held firm in a slowly revolving carrier. The carrier was advanced towards the cutters by way of a long lever like handle. After a few seconds the chair leg was completed, removed and another Beech blank put into the carrier and the process repeated.
These lathes were only viable for long production runs of identical objects and such a lathe would have represented a sizeable investment. Careful consideration of all the pros and cons would have been essential, and direct comparisons with pole lathe production assessed. For instance, would enough work of an identical nature be forth coming? Frequent stopping of production to change cutters for short runs is time wasting. Unlike the pole lathe turners who used comparatively cheap green wood the semiautomatic lathe required more expensive dimetioned seasoned timber from the local sawmill.
There was a time saving in as much as this timber was ready prepared and ready for use where as the chair bodgers had to convert theirs from the whole tree. Convenience was also a factor, the whole operation could be undertaken on one site, in the case of Bert Saunders this was a large ramshackle wooden workshop in the village center. I still remember the gentle hum of machinery escaping through the leaning dust encrusted weather boarded workshops. When I was very young this seemed a place of remote mystery. It was many years later, just before demolition to make way for flats that I entered into the gloomy interior to record another little bit of passing history.
Ercol is a name synonymous with Quality furniture. This High Wycombe Company was established by Lucian Ercolani in 1920. He was a great believer in mechanization and claimed to be the first of the chair masters in the town to put the flat belts that drove the machines under the floor for safety.
During the 1970s the firm installed a ‘turning line’, a complete system that is fed with squared blanks at one end and from the other a completed chair turning emerges ready for assembly. Manufactured by the German firm Hempel it was developed in collaboration with Ercol. It is a copy lathe: that is to say a template that dictates the path of the cutter determines the shape of the turning.
Starting with a pallet load of sawn squares the operator feeds a moving horizontal chain-like conveyer that takes the blanks through to the first operation. Twin saws trim each end to the required length; the blank is carried onward to be automatically located between lathe centres and set spinning. A traversing ‘stay ring’ (steady) ensures there is no ‘whip‘, this travels from right to left immediately in front of the fixed cutter who’s path is dictated by the template. Upon completion of this move the stay ring and cutter return and two other ‘chisel’ cutters move in to form a round tenon at each end (chair stretchers were being turned on my visit).
If holes are required they are bored automatically on their conveyor journey towards the sanding section. Here the turning is again centered and revolved at high speed against a series of sanding paper grades cushioned against flexible brushes comprising of a vegetable fibre. As the turned stretcher slowly exits the sanding section, still held on the conveyer it is delivered to the end of the machine for final trimming to length, and in the case of a chair leg, a slotted through tenon can also be cut at this stage. For such a machine to run economically very large runs of the same item are needed. The Ercol Hempel lathe requires a breakdown time of approximately eight hours to change from producing one design to another. When running at full capacity the Hemple is capable of turning 365 pieces per hour.
Here’s a thought, are the hand turners of history now turning in their graves?
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