Marking Out and Measuring Materials

Marking out requires two straight edges on the material.

The straight edges are at right angles to each other and are used as references.

These references are called datum references.

Checking the Datum References

steel rule -> check the straightness of an edge

try square -> check whether two edges are at right angles to each other on wood or plastics

engineer’s square -> check whether two edges are at right angles to each other on metal or plastics

Marking Mark

scriber -> mark lines on a metal workpiece

sharp pencil -> mark lines on a wooden workpiece

spirit-based felt pen -> mark lines on bare plastics

Marking Lines at 90° to an edge

Use an engineer’s square and a scriber to mark a line at right angles to the datum edge of a metal workpiece.

Use a try square with a pencil to mark a line at right angles to the face side or face edge on a wooden workpiece.

A marking knife is used with a try square to cut a line across the grain of a piece of wood where a section of the wood needs to be removed.

Marking Lines Parallel to an edge

odd leg calipers -> mark lines parallel to the datum edge on a metal or plastics workpiece

Odd-leg calipers can also be used to find the centre of a round bar.

marking gauge -> mark lines parallel to the face side or face edge on a wooden workpiece

A marking gauge can be set using a steel rule.

Marking Curves, Arcs and Circles

spring dividers -> mark circles or arcs on a metal workpiece

pencil compass -> mark circles or arcs on wood or plastics workpiece

Marking Freeform Shape

template -> mark out a freeform shape; to mark out more than one shape identically

A template can be made from card or paper. Then cut and paste it directly on the material surface.

Punching Mark

ball-pein hammer -> punch marks on metal workpieces by striking a punch

centre punch -> mark the centre of a hole that is to be drilled on a metal workpiece

dot punch -> mark small dots (witness marks) along a scribed line on a metal workpiece

Measuring the Size

steel rule -> measure lengths on all materials

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