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| - CHAPTER VI THROWN SHAPES "The lyf so short, the craft so longe to learne." CHAUCER. THE wheel is the true fountain head of all beautiful shapes, and the student who would become a potter cannot get "on the wheel" too soon. Throwing, sometimes spinning, is the term applied to the mak- ing of shapes on the wheel. Interesting and really fine pots may be built or cast, but the ultimate appeal rests with the thrown shape. Unfortunately, a complete mastery of throwing is not to be gained by a few spasmodic wrestles with the wheel. It comes only with long hours of con- centrated effort. Having watched an accomplished 59 60 thrower and seen the full round shapes rise so easily between his dexterous fingers, it is with a severe shock that one realizes at the first attempt the skill and practice that will be required before such a desirable proficiency is attained. The best kind of wheel is the kick wheel shown in the illustration. With this the feet, hands, and head work in harmony, accelerating or retarding the motions as required. It is a not distant rela- tion of the earliest wheel, which was a heavy head on a short shaft, pivoted in a stone socket. Set spinning by hand, it was kept revolving some time by its own momentum. This form of wheel is used even to this day in the near and far East. Its first development was a secondary wheel and driving band turned by hand. This led to the wheel shown in the frontispiece and to the kick wheel and again on to the factory wheel. This in its turn is being superseded by the steam wheel, which gears onto a running band, the foot being used to start, stop, and regulate the speed. The two last named were introduced with the idea of accelerating the production rather than the improvement of the shapes. No doubt the now primitive kick wheel, much as used by the potters of the Renaissance, will be found good enough for us. The tools required for throwing, after the wheel itself is secured, are as follows : a thin copper wire 61 THROWING^ f tWINGTOOL/ FIG. 27. 1, "Rib" ; 2, Modelling Tools ; 3, Pricker; 4, Sponge; 5, Wire; 6, 7, and 8, Shaving Tools; 9, Leather. twisted between two bits of wood, a pricker, a fine soft sponge, another bit of sponge tied to a stick, one or two modelling tools and a rib (see Fig. 27). The clay is first knocked up into shape ready for the throwing. To do this it is wedged, a fair-sized piece being taken in both hands and thrown vio- lently down on the bench, cut across, and smashed together again. This process is repeated until all air bubbles are expelled. This is ascertained by cutting with a wire. The finger is then passed across the surface to tell if it is well together, and 62 not hard and soft in streaks. If, as must happen in a small pottery, the clay is out of condition, it is best remedied by cutting it with the wire into thin slabs, piling them criss-cross and then wedging the mass. If still streaky, it can be quickly tempered, piece by piece. A double handful is torn across, wedged together at a different angle between the hands, re-torn, and re-wedged, until hard and soft are welded indistinguishably together. This thorough wedging is essential, as with begin- ners a small lump or bubble will usually be sufficient to bring about the collapse of the shape. The clay being thoroughly wedged is rolled into balls of a convenient size. For first practice they should be on the small side and moderately tough, as this allows a little more play before the ball becomes too soft. The wheel is now started revolv- ing from right to left (see cut). The head being clean, the ball is thrown smartly onto its centre. The hands are now wetted in a bowl of water, which is put, together with the tools, on the shelf to the right. Then gently but firmly, with hands placed as shown in Fig. 28, the ball is centred. At this stage, perhaps the most critical of all, the wheel should revolve quite briskly. The hands should be moistened if inclined to stick and the left hand held steady, the elbow pressed into the side, the fore- arm hard on the rest. The right hand has more 63 CEhT 'RING. FIG. 28 freedom and coaxes the ball into a half sphere. This when dead centred is elongated, pressed down again, and re-formed into a truncated cone. The left hand still steadying, the thumb of the right is pressed firmly into the centre of the top, down and out, to hollow the ball (see page 18), but stopping short of the lathe head. At this stage the most convenient shape to form is a cylinder, its walls grad- ually diminishing upwards with a little fatness at the rim. To do this the wheel is slowed down a little and the fingers of the left hand inserted. The sides are felt and gently pulled up, between the left index finger and the two first fingers of the right hand, gradually higher and thinner, always endeavouring 64 PU JNGUP Fio. 29 to keep the walls at an even but slightly tapering thickness. (Fig. 29.) At first two fingers only will be inserted, but as the shapes grow in size the whole of the left hand will gain admittance. Then the perfect cylinder may be modified to almost any required form. With narrow-mouthed shapes the opening must be kept as small as possible, for the clay once pulled out it is difficult if not impossible to compress it again. The centring and hollowing once mastered, the chief difficulties to avoid are getting the bot- tom of the walls too thin before the top is pulled up, and making the top wavy and irregular. If the lat- ter happens, it should be at once cut back with the 65 OUT SIDE- METAL pricker, which is also used to test the thickness of the sides and base. When the shape has been pulled up to the required form and is sufficiently thin, the top is smoothed and fattened between the fingers. This not only im- parts a look of substance to the vase and takes away any cast look, but gives strength where it is most needed. The inside, if wet, can be cleaned out with the stick sponge and the out- side lightly smoothed with the other sponge. For the insides of bowls or wide- mouthed shapes, a rib of slate or zinc (see Fig. 30) will be useful for obliterating ridges. The last operation is to pass the wire, held firmly to the wheel head, beneath the pot and lift it off and place it on one of the pot boards or plaster discs. (Fig. 32.) The first primitive forms are far better left frankly for what they are. Afterwards when bigger and more finished shapes are attempted, they can be thinned and refined with the aid of the rib and a modelling tool, a considerable finish being put on OOONE- EOlk INSlDt. FIG. 30 66 FINISHING WITHW FIG. 31 67 WIRE REMOVE FIG. 32 before they are removed from the wheel. With bowls or large shapes it will be found impossible to lift them off without destroying the shape in some degree. For these wood or plaster discs will be required. The plaster bats need soaking in water before use and the wood must be three-ply to prevent warping. These discs are centred on and firmly stuck to a layer of clay run out on the wheel head, and when the pot is finished they are removed with it. All this sounds very simple, but the beginner will do well first to practise and master centring 68 the ball. Until this be done, the rest of the work is worthless. After this must be practised the pulling up, the pressing down, and the forming of truncated cones, then hollowing the ball and pulling up into a cylinder. A true cylinder accomplished, it is easy to branch out into simple wide-mouthed vase forms. As the skill increases, shapes with double curves and long or narrow necks may event- ually be achieved. Throwing to a set copy induces a necessary concentration at this stage, but once a mastery is attained, shapes seem to suggest them- selves. A small mirror placed so as to reflect the true form will be found of great service. When pairs or several duplicates are required, a drawing of the yTACEy- FROM-CENTKE D BALL TOTORNID-yHAPf- FIG. 33 exact profile must be made and a "rib," of zinc or slate, filed to fit. Without such a guide the match- ing up is well-nigh impossible. When watching a clever thrower in a factory mak- ing some difficult and probably horrible vase, it is 69 intensely interesting to see the fine forms evolved in the process. To the artist the impulse to stop him is almost irresistible. It was there that the old masters showed their wisdom and restraint. They stopped at the right moment and none of their shapes descend to the merely clever. There is a nobility about a large vase lacking in a small one. Once the appetite be whetted for big pots the desire for size seems insatiable. The only way out, except for the born thrower, is the two- or three-piece vase. The Chinese were masters of this as of every other process and we find that they frequently made vases of quite moderate size in two or three parts, sticking the pieces together with consummate skill. This process, however, should never be attempted until considerable proficiency has been gained in throwing to a drawing, for in any but expert hands it is doomed to failure. The shape must be care- fully drawn out on paper and the sections marked off and then thrown exactly to size. Any deviation means endless trouble, with eventual disappointment. For this difficult work the student unable to de- vote a lifetime to throwing will find a removable wheel head a necessity. Then a slotted one can be screwed on which will allow a plaster disc to be shipped back into exactly the same position, thus sav- ing the difficult task of re-centring. For prolonged 70 HALF 5ECQNDHAL? TOP KEPT MOIST HALVE5 IN POSITION FINISHED SHAPE FIG. 84 operations these plaster discs require to be shellacked to prevent the work leaving. To start with a shape as shown in the illustration might be attempted. (Fig. 34.) The drawing made full size is hung in full view. Then the gauge is set to 71 the exact width of the joint. The bottom half is first made, being cut square and true with the pricker. The drawing is reversed and the upper half thrown, the neck being at the bottom with a fair amount of waste beneath. When each part is trimmed accu- rately to measure, they are put aside to toughen. The top portion will stiffen just as required, leav- ing the neck still moist. The bottom half will need watching to prevent the upper edge drying before the base gets firm enough to support the top when attached. A damp cloth lightly wrapped round it will help to insure the ideal condition for sticking up, which is a gradually diminishing state of toughness from the base up to lip, the junction of the parts being in exactly the same state. When fit to handle, the top half is cut through at the lip, allowing a trifle for finishing off. Next the bottom half, still firmly fixed to the bat, is slotted back into its original position on the wheel. The flat surfaces that have to be applied and stuck are now very carefully and slightly roughened, then painted with thick slip made from the same body. These two wet edges are now applied and gently and firmly pressed into position, the wheel being slowly revolved to see if the two halves run true. When well together and apparently sticking, a little wedge of soft clay can be carefully run in all around the joint. This operation should be very thorough, and the clay wedge must be carefully welded into the sides of the joint. This is finished off on the outside with the rib and the inside very lightly smoothed with the fingers. During this process the top should be covered with a soft wet cloth, then when the joint has been made good and will stand the slight strain, the lip is finished off in the ordinary way. With three-pieced shapes the lip can be finished before sticking up, as the last part is thrown in its right position. If at any time the shape shows a disposition to leave the plaster bat, it should be stuck down with wet clay. The toughened shape can now be turned down in its upright position, cut off the bat, and the base hol- lowed in a chuck (see next chapter). Ipdia. B. CategorÃa:Pottery, for artists, craftsmen & teachers
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