Diagram Drawing Centre Punch
Points can be supplied with single characters up to 3mm double characters up to 24mm and treble.
Diagram drawing centre punch. Workshops use punches for locating centers for drawing circles to punch holes in sheet metals to start holes for drilling to remove damaged rivets bolts or pins and to transfer location. The punch point can be replaced without having to remove the whole of the point holder. A punch is a hard metal rod with a narrow tip at one end and a broad flat butt at the other.
Centre punches available in four sizes each with a chemically blackened knurled grip and a round head a fine machine ground point with a 90 chamfer gives accurate centering on cross lines and makes well defined impression for drilling the round head provides a large face for striking and also. When used the narrower end is pointed against a target surface and the broad end is then struck with a hammer or mallet causing the blunt force of the blow to be transmitted down the rod body and focused more sharply onto a small area typically woodworkers use a ball peen hammer to strike a punch. An automatic center punch is a hand tool used to produce a dimple in a workpiece for example a piece of metal.
It performs the same function as an ordinary center punch but without the need for a hammer when pressed against the workpiece it stores energy in a spring eventually releasing it as an impulse that drives the punch producing the dimple. The e172 is a heavy duty automatic marking punch can be supplied with a special mark number or letter instead of a punch point thus providing an ideal method for an inspector to place his mark on work. The dot punch is a lighter.
Centre punching is a bit of an acquired art or skill same as riveting or peining. 18a automatic center punch 18 automatic center punches steel automatic center punch 5 125mm length 9 16 14mm punch diameter the starrett automatic center punch with adjustable stroke features a lightweight knurled steel handle for a positive grip and easy handling. The centre punch is made form mild steel with the point hardened and tempered so that it withstands impact with the material it is marking.
Download clker s centre punch drawing clip art and related images now. I have a perfectly serviceable spring loaded automatic punch used it twice didn t like it put it away in the draw and is not likely to be used any time soon. Jan 18 2015 diagram showing how an automatic center punch works.
Mechanical engineering workshops extensively use various types of punches.
