HOW PINS ARE MADE.

Lyttelton Times, Volume CXXIII, Issue 15901, 12 April 1912, Page 11

HOW PINS ARE MADE.

(“ Harper’s Weekly.”)

Although the manufacture of a pin is less complicated than that of a needle, the pin requires many manipulations to fit it for market. Most of the pins used are of yellow copper dr of iron, but commerce also demands pins made of steel. By the common method of manufacture the metal is cast into cylinders a little less than three feet long and a little more than a foot in breadth. The- cylinders are seized by a wire-drawing machine; drawn fine, and hammered, or rolled, until fit for the bench, where, they are reduced to the desired diameter.

That is tho old process. In the. latest improved method red copper and zinc are put into tho crucible, and the amalgam obtained by fusing the two metals is run into moulds to form oval plates, experiment having proved that labour and expense are saved by using that form rather than tho circular. Tho plates are sheared and then cut into wires. While being cut they are HELD FAST BY MASSIVE CLAMPS. At this point a device similar to a glazier’s diamond is driven down upon the plates by a simple, truck-like machine consisting of four grooved wheels and a chain run over a pulley. While tho plate is held in position by the nippers or clamps its outer edge rests against the tangent of two circular shears mechanically turning in opposite directions. The machine starts, the shears work, and tho metal slats or wires receive their points and are cut into square sections, which are seized by workmen and hooked to one of tho shears posts. The wire-drawer draws the plate along and the shears force it to turn. 'While the shears are paring Vti into the required shape the sixtyMJAYnd weight drags tlio truck along, pressing on the shears. The work is simple and practical; the shears cut incessantly until tho plate is pared to the diameter of forty-five milimetres. Tho wire given by the square section goes to the wire-drawors, where tho ends are pointed by file or by hammer and passed on to tho drawing-frame. Tho drawing-frames for the wires intended for the finest size of pins are formed by “black diamonds” carried by steel chassis. The diamond is an important tool of tho pin manufacturer ; every diamond demands fifteen days’ labour for its piercing, and costs thirty dollars. The upper part of tho pin wire drawing-bench is like a bowl. In it is soapy water, the bath into which the machine and the material are run. The bath lubricates the wire and fits it for the work which follows. After each visit to the bench the wire is dipped in a ten per cent solution of sulphuric acid and washed in pure water, then

WASHED IN BRAN WATER AND DRIED. j Whether the wire is brass or iron, it goes on tho rollers to be mechanically turned, drawn and straightened. It presents its extremity and is instantly i met by a little mallet which gives it I the three short, sharp raps which form ! its head. The fully formed pin wire, I with its heads, is cut into sections. As | the sections are cut they fall on a I grooved slide. Tho groove catches the ■ pins by their heads and, with heads caught and bodies hanging,, they are manipulated by a long, rapidly revolv- , ing moulder running on a horizontal , axis. ! Tho pin is then subjected to four ac- | tions. It is pushed away from the | machine from behind, pushed . to the j side of the slide, drawn back and then j forced forward, revolving as it moves ; on. As the pins advance along tho screen or sieve their bodies lie almost wholly on the runner. When they reach the end of'tho long screen they fall, one by one, in a box set to catch them.

Pins are not fit for the market until guaranteed against oxidation. Tho brass and steel pins, previously galvanised, are bleached in a bath of hot salts of tin. After the salt bath the butt is emptied and the pins are washed in water and put in sawdust in turn-ing-barrels for ten minutes. Then they are taken from the barrel and put in the sieve of a fanning-machino and FANNED UNTIL THEY ARE FREE FROM SAWDUST. When absolutely clean they are sifted into a receiver. The pins go from the receiver to a metallic reservoir attached to the “ papering ” machine, and a woman (brushes them on to a thirty-nine barred grating whose bars are so close together that the pins’ heads cannot pass. The pins, points down, hang through the bars. When the grating is full of pins tho woman tending it runs a long strip of paper under the roller and starts tho machine. , The sluice bar of tlie grating rises and as ono row of pins passes out a second bar bears down on the pins’ heads, forcing the pins to run their points evenly and regularly through tho paper. The simple but effective manoeuvre is repeated until twelve rows of fortv pins each have been mounted on paper. Tho pin is now ready for marketing.