Some Hints on Using the Tools.
—(1) When you want to rivet something use the ball pein end of the hammer to pound down the end of the rivet as this will spread it out in every direction evenly and you can make it nice and round. (2) Side cutting pliers are useful to hold and bend bits of metal with and to cut off pieces of wire as well. (3) Tinner’s snips are simply large powerful shears and you can cut sheet metal up to ³⁄₃₂ of an inch thick with an ordinary pair. When you cut a sheet of heavy metal with them let the lower blade and handle rest on your bench and you can get a better leverage on it. Metals that are thicker than ³⁄₃₂ inch must be sawed.
(4) While metals can be sawed by using a special saw blade in a scroll saw frame you should use a jeweler’s saw frame with jeweler’s saws for metal—I prefer the Fish Brand for fine work. (5) For heavier work use a machinist’s hack saw; put the piece of metal in a vise and have the part you want to saw close to the jaws of the vise so that it will not vibrate; use a little pressure on the outward, or cutting stroke, and let up on it as you draw the saw back or you will dull the teeth.
(6) In using twist drills, and these are the only satisfactory kind for metal work, be mighty careful not to press too hard on the drill stock and don’t try to crowd the drill into cutting faster than it will cut at the speed with which it is turning. In drilling iron keep plenty of oil on the drill point.
(7) You can measure much more accurately with a steel rule than you can with a wood rule and whereas measurements in cabinet work down to ¹⁄₁₆ inch are close enough, for metal work it should not be more than ¹⁄₃₂nd of an inch, and for machine work make your measurements to ¹⁄₆₄th of an inch. (8) A small steel square is better in every way for metal work than a carpenters’ try square but you will find it quite expensive.
(9) The advantage of spring dividers over the ordinary kind is that you can set them very accurately and they will stay where you set them. In scribing a circle with a pair of dividers mark the center with your center punch first as this will prevent your dividers from slipping.
(10) Inside calipers are used for measuring the inside diameters of cylinders and the like, and, conversely (11), outside calipers are used for measuring the outside of anything that is round. In either case you measure the distance between the points of your caliper with your rule to find the diameter of the thing. (12) A center punch is always useful to make a starting point in metal with, for it can’t be rubbed off or lost sight of.
(13) A set of taps and dies to cut screw threads with in metal of whatever kind is a joy forever. All metal work becomes easy if you have a set of these screw cutting tools and it is next to impossible to make things if you haven’t got them.
When you are cutting threads in a piece of metal with the tap, the hole in the metal must of course be a trifle smaller than the diameter of the tap; the tap is put into a handle called a stock and as you cut the threads in the metal don’t turn the stock continuously around but give it one complete turn forward and then half-a-turn backward and you will be less apt to break the tap.
The same method holds good when you are cutting threads on a rod with a die; in this case the rod must be a little larger than the hole in the die. In threading iron use plenty of oil on the tap or die, but for brass and the softer metals a lubricant is not needed.