Blow Lamps.
—A soldering lamp is used sometimes in the place of a blowpipe, and it should combine perfect security with compactness and portability. Tool merchants’ catalogues show a number of styles. In the lamp shown by [Fig. 34], benzoline is burnt. When the lamp is in use and the body of it is very hot, the inside pressure does not exceed three-fifths of an atmosphere, whether the regulator R is open or almost closed. Thus the danger of explosion, which is such a drawback to some of the lamps that use ordinary paraffin, is avoided. The upper parts of the lamp are subjected to great heat and therefore are packed with asbestos, which serves as a filter and stops any impurity in the benzoline from getting to the burner. The flame can be lowered to a glimmer when not actually in use, thus saving the trouble of relighting. When the lamp is to be used, the regulator R is screwed up tight; and care must be taken to ascertain, from time to time, that the burner or nipple C is open and perfectly clean. If this becomes obstructed, it can be cleaned by unscrewing the tube T and passing a fine steel wire through the hole. The lamp should be completely filled with benzoline every time it is to be used. A little methylated spirits is poured into the basin A, and set alight. When the apparatus has become slightly warm, the regulator is opened gradually. To extinguish the flame, the regulator must be screwed up tight. If any escape is observed round the screw of the regulator, the square P should be screwed up with the key supplied by the makers, so as to tighten the asbestos packing. The lamp above described is only one of a great number of such appliances, but it is fairly typical of them all. The difference between a solderer’s and a brazer’s blowlamp is merely one of size and power.
Fig. 35.—Soldering Lading-can handle
Fig. 36.—Soldering Lug to Lamp Bottom