This section is from the book "Turning And Mechanical Manipulation", by Charles Holtzapffel. Also available from Amazon: Turning and Mechanical Manipulation.
The art of turning in softwood produces numerous useful and elegant results for domestic, personal and manufacturing purposes; it requires comparatively few and simple tools, but affords considerable scope for ingenuity and skill, in suitable design and in its application to the material, and in the use of the tools. The devotion of a little time and care to acquire a moderate proficiency in this branch of the art is very advisable. The acquisition of a sufficient mastery in the management of the gouge and chisel being especially advocated, as it not only greatly simplifies the use of the other softwood tools, but, the confidence and facility thus attained, remove many difficulties in the ordinary practice of hardwood and metal plain turning.
For elementary practice with the softwood tools, the production of the simple planes and solids, viz., the cylinder, surface and cone, the internal cylinder, surface and cone, and subsequently, the sphere and internal hemisphere, are offered as sufficient types of procedure. The manipulation acquired in turning these forms, may be readily applied to any others, more complex in shape or detailed ornament; for such forms, however elaborate, may always be resolved into combinations of the simple primary figures named. Examples of the production of combined forms, shown by some objects in ordinary use, together with some more elaborate works in the soft woods, will be found in later pages.
It should be premised, that in all the branches of the art of turning, as in all other handicrafts, there exist many variations of practice; to suit the convenience of the operator, the conditions of the material and the tools available, or, arising from peculiarities of local habit. These variations are not generally of sufficient importance for detailed notice, and the observations in this and following chapters, are intended rather to meet the ordinary requirements of the amateur turner, than to supply an exhaustive description of all the various methods that may be available in hand turning.
The position in which the operator stands when working at the foot lathe, is very little influenced by the material, but varies with the form of the work upon which he is engaged. When the work is of the cylindrical character; he stands square, facing the lathe bearers, the body held fairly upright supported on either leg held rather rigid at the knee and ancle joint; the toes pointing outwards and an inch or so distant from the front rail of the treadle. The ball of the other foot rests on the front edge of the treadle, the toes also pointing outwards, so that the heel of the treadle foot and the hollow of the supporting foot are about opposite. The occupations of the two legs are exchanged from time to time, and in the majority of cases, it is quite unimportant upon which leg the body is supported. The tool however being held in the right hand, it becomes stiffened and as it were braced together with the entire right side, when the body stands on the right leg; and that position, is therefore naturally adopted for all cuts demanding especial care and exactness.
With work approaching the surface character the same general position is employed, but the body is slightly turned to be more in face of the work, and stands at an inclination of about 45° to the bearers. This is often insufficient for surfaces and internal work; the operator then stands on the right leg, facing the surface and at right angles to the bearers leaning against them by the right hip, the right foot parallel with the front rail of the treadle, the left leg crossing over the right shin in moving it.
To set the lathe in motion, the driving band is taken between the left finger and thumb and pulled downwards, the foot at the same time being placed lightly on the treadle, without exerting any active pressure. The consequent partial revolution of the fly wheel causes the bend of the crank to rise and lift the treadle, until, the crank having passed over the vertical position, the treadle commences to descend, at which instant the pressure of the foot is first exerted upon it. The descent of the treadle enforced by the foot, continues the revolution of the fly wheel, causing the treadle to rise again to be again depressed by the foot and so on. In keeping the lathe in motion or in treading the lathe, the regular intermittent pressure given by the foot is always commenced gently, gradually made more forcible during the first part of the descent of the treadle, and as gradually reduced towards its termination: at which and during the upstroke, the pressure is entirely relieved, although the foot still remains in its place. The actions described are readily and almost instinctively acquired. The foot generally remains continuously on the treadle, but occasionally when the lathe has been set in sufficiently rapid motion, it may be removed from it, should the operator desire to stand for a few moments upon both feet, to be perfectly steady while making a cut requiring more than usual precision.
The pace at which the treadle is moved, in other words the velocity given to the fly wheel and conveyed to the mandrel, necessarily varies in all cases with the diameter of the work; for should the revolutions of the mandrel remain at one constant rate, the surface velocity of the work will increase in the ratio of its diameter at the point under the tool. Therefore to attain the uniform surface velocity most suitable to the material and the action of particular tools, works of small diameter require driving faster than those of large.
This necessity is equally felt when the form of the work combines portions greatly differing in diameter in one solid, or, upon the simple plane or surface, upon which the surface velocity gradually diminishes from the circumference to the center. In the latter case, the driving band being arranged for a speed suitable to the medium diameter of the surface being turned; the revolutions of the mandrel may be so varied, as to attain a sufficiently near approach to uniform surface velocity in the work, by treading the lathe a little faster or slower, as the tool approaches its center or circumference.
The same variation generally suffices for cylindrical work of varying diameter; although it may be sometimes convenient, to shift the driving band to different speeds, suitable to the different diameters of the work, as these are successively turned. Large diameters of all materials force the operator to tread the lathe at a relatively very reduced speed, necessary in turning iron, among other reasons, for the preservation and correct action of the tools, but, principally requisite in softwood turning, the other extreme, to avoid too great bodily exertion.
Softwood, in comparison with hardwood or metal turning, requires the highest rate of speed, and it may be said, in respect of the lathes described in this volume, that when employed for works up to two or three inches diameter in softwood, it is hardly possible to employ too high a velocity. The driving band should then run from one of the larger grooves on the fly wheel, to one of the smaller on the mandrel pulley. It may occupy a pair of grooves of medium size, for work from three to six inches diameter; while for larger, a still less speed is desirable, in order that the work may not become inconveniently laborious.
 
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