Dimensioning
Radii
All
radial dimensions are proceeded by the capital R. All dimension
arrows and lines should be drawn perpendicular to the radius so that the
line passes through the centre of the arc. All dimensions should only
have one arrowhead which should point to the line being dimensioned. There
are two methods for dimensioning radii.
(a) shows a radius dimensioned with the centre of the radius located on the drawing.
(b) shows how to dimension radii which do not need their centres locating.
Spherical dimensions
The radius of a spherical surface (i.e. the top of a drawing pin) when dimensioned should have an SR before the size to indicate the type of surface.
Page last updated by Paul Hudson
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