Metal Measuring and Laying-out Tool

Objectives

After reading through this content module, the reader should be able to Describe / define what measuring and laying-out tools are used for: State the name of common measuring and laying out tool: State the uses of common measuring and layingout tools: State the rules that applies to the safe use of measuring and laying out tools:

What Is Meant by Laying Out?

Laying out is the marking of lines, circles, and arcs on metal surfaces; such work is called layout work. It is the transferring of information from a working drawing to metal surfaces to show the machinist or the fitter at the workbench how much metal should be cut away. Laying out on metal is the same as making a drawing on paper, the difference being specific tools are used.

Measuring tools:

Measuring tools are tools used when taking measurements or to transfer measurements to metal parts or components that are being worked on in the workshop. Some tools are used in conjunction with other tools when taking measurements

Scriber:

The scriber is a piece of high carbon steel hardened and tempered they are

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Scriber with Label

generally about 6” to 10” long, pointed on one or both ends like a needle. It is held like a pencil to scratch or scribe straight lines on metal. Scribers with bent end are used to scratch lines in places where the straight end cannot reach. Scribers are sharpen on an oilstone. As a safety precaution scribers should be carried with the point facing down and should never be placed in your pocket.

Centre punch

The center punch is used only to make the the centers of holes that are to be drilled.

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Centre Punch with Label

They are made from high carbon steel hardened and tempered. The point angle of the centre punch is between 60 degrees and 90 degrees. A ball pein is used in conjunction with the centre punch when marking the centre of holes to be drilled. Centre punch with mushroom heads shound not be used as a safety precaution. The centre punch should also be firmly held while in use.

Callipers

Common callipers used in the workshop may be

1. firm or plain joint or
2. spring type

and may be identified according to their function and style of manufacture. These include