Tools Used in Metal Spinning
Fig. 37 shows an attachment which is used to roll any bead or form. This tool, when in use, is inserted in the tailstock spindle in place of the regular center. It is adjustable for any diameter. The roll illustrated is for making a sharp turn, but rounds and other forms are used. The shell being spun by this tool should be held on a hollow chuck. The roll is set at a point where the metal is to be turned over, and by its use the curve may be governed and made uniform with less skill than when the work is done by “air spinning.” In addition, the spinning may be done in less time. This attachment, for some shapes, makes the use of sectional chucks unnecessary.
Fig. 37. Attachment used for Rolling Sharp Turns and Beads
Fig. 38 shows several spinning tools, the heads of which were turned in the lathe instead of being forged. This method of making spinning tools is believed to be original. The spinners prefer them to the tools which are forged in one piece, because the heads which are screwed to the shanks are made of the best quality of steel, such as the high-speed or self-hardening steel. The shapes are also better and the surfaces more true. The heads of these tools are all threaded with standard ¼-inch, ⅜-inch and ½-inch pipe taps, according to the size. Obviously, a spinner can have as many different shaped heads as may be required of each of the sizes given, and only one handle. The tapering threads in these heads insure that they will always screw on the shanks tightly no matter how often they may be replaced. The ¼-inch size takes a ½-inch cold rolled holder; the ⅜-inch, a ⅝-inch holder, and the ½-inch, a ¾-inch holder. These will be found large enough for the heaviest work. The egg-shaped tool A is a good form for roughing or breaking down, as it has plenty of clearance on the heel, and a blunt point that will not tear the metal. This tool is shown in four sizes. The ball or spherical tool B is a good one to use on curves and large sweeps. The tool C is elliptic, and is slightly different from A, as it has a blunter point. One of these heads is shown at D screwed onto a reducer by which it is held in the lathe chuck while being turned. These heads or points can also be turned while on the handle by using a steady rest.
Fig. 38. Metal Spinning Tools with High-speed Steel Removable Heads
A group of trimmers, skimmers and edgers is shown in Fig. 39. Three skimmers of the built-up type are illustrated, the shanks being of machine steel and the blades being riveted to the holders. These blades are made of either high-speed or regular steel. Skimmers which are forged in the regular way from one piece of steel, are shown at B. A number of edgers C, which are made of high-speed or self-hardening steel, are also illustrated. These tools are used without handles until they are worn down short, after which tangs are forged on their ends and they are used in handles. Edgers are utilized on all kinds of work for trimming the ends of the shells. The skimmer is seldom used on metal chucks, but mostly in connection with wooden chucks, where the metal cannot be smoothed down with a planisher. The skimmer is run over the metal lightly, taking a thin shaving and smoothing the uneven surfaces. It requires considerable skill to use this tool without wasting the metal. The surface of the work is finished with emery cloth after skimming.
Fig. 39. Tools used for Trimming and Skimming Spun Work
Figs. 40 and 41 show a number of spinning tools of various shapes. The letters A indicate the breaking-down or round-nosed tools of different sizes. This type of tool, which is finished smooth and has a blunt point, is used for forming corners and sharp angles, and it is the tool most commonly used by spinners. The planishers and burnishers B are used on all convex surfaces and for finishing on metal chucks where there is to be no skimming done. The tools C are known as hook or poker tools, and they are used to turn up beads or curves from the inside of the shell. The holders having rollers are used for turning over beads, the metal first being trimmed and turned to a vertical position. The other shapes shown are irregular tools for special work and they are not in daily use.
Fig. 40. A Group of Spinning Tools of Various Shapes
Fig. 41. Another Group of Spinning Tools
Two pairs of spinners’ pliers for turning over the edge of the metal when making large curves are shown in Fig. 42. The wedge-shaped pieces shown in this illustration are used when breaking down or roughing shells to give a bearing to the metal in order to prevent it from wrinkling or buckling when changing its formation. These pieces are made of hard wood with the exception of the one to the right, which is of steel. When one of these pieces is in use it is held in the left hand at a point directly opposite the spinning tool, the metal being between the two. Wood is preferable in most cases, as it does not harden the metal blank.
Fig. 42. Spinners’ Pliers which are used for turning the Edge of the Metal when making a Large Bend
The tools shown in Fig. 43 are used in spinning steel. The round tools are of drawn brass, and they can be used where the steel tools cannot, for while a steel tool is perfection on brass, a brass tool is the only thing on steel. It wears out, however, much more rapidly than one of steel. The rolls shown in the center are used for breaking down steel shells. These tools are hardened and have hardened roller bearings. The handles are made of one-inch iron pipe, which is filled with lead to give weight and strength.
Fig. 43. Some Spinning Tools used in Working Steel
Hard wood tools that are used for breaking down large thin copper blanks ranging from 2 to 5 feet in diameter are shown in Fig. 44. These tools are also used where the surface that the tool will cover without hardening the metal is important. Blanks which are broken down with these tools are finished with the regular types.
The handles of spinning tools vary in diameter from 1¼ to 1¾ inch, and in length from 16 inches to 20 inches. The tools should project from the handles from 9 to 18 inches, and the total length of the tool and handle should average from 30 to 34 inches.
Fig. 44. Wooden Tools which are used on Large Thin Copper Blanks
A group of wood working tools is shown in Fig. 45. These tools are of the type commonly used by spinners for turning the various shapes of wooden spinning chucks. As the tools illustrated are the kind regularly used for wood turning by patternmakers and other wood-workers generally, they will need no description.
Fig. 45. Wood-turning Tools which are used in turning Spinning Chucks