Engineering Graphic Modelling

1.0

MODELLED PROPERTIES

SUMMARY

A property may be defined as a characteristic of an object, e.g. a

machine, but this definition does not clarify precisely what the

property is.

A machine, e.g. a screw-jack possesses a series of properties — shape,

function,

lifting capacity, use, reliability, resistance to corrosion,

size,

colour, etc. Here function is special because it characterises the

machine, and justifies its existence i.e. the screw-jack can lift a weight.

Five other properties: structure, form, material, dimension and

surface are special and are BASIC PROPERTIES. These properties

are established as the design proceeds i.e. they are