scope:

This specification covers the general requirements for scales made of wood, plastic, metal, and combinations thereof.

Scales furnished under this specification shall be of the types, shapes, compositions, grades, and sizes as specified and identified by a type designation number (see 6.2).

Scales covered by this specification shall be identified by a type designation number formed as indicated below. This type designation number is intended for cataloging and ordering purposes and not for surface printing on the scales Sub-paragraphs 1.2.1.1 through 1.2.1.10 indicate the options available for each type scale.

GG-S-161 X X X X X Spec. No. Type Shape Composition Grade Size (1.2.1.1) (1.2.1.2) (1.2.1.3) (1.2.1.4) (1.2.1.5) (1.2.1.6) X X X X Scale Numbering Style Sheath, if graduation required (1.2.1.7) (1.2.1.8) (1.2.1.9) (1.2.1.10)

The scale specification number shall be GG-S-161.

The type of scales shall be designated as follows:

Type I - Scales, drafting: architect's. Type II - Scales, drafting: engineer's Type III - Scales, drafting: mechanical. Type IV - Scales, drafting: combination English and metric measurement system. Type V - Scales, drafting: surveyor's. Type VI - Scales, drafting: decimal-inch dimensioning. Type VII - Scales, plotting. Type VIII - Scales, plotting: metric. Type IX - Scales, plotting: feet and yards. Type X - Scales, plotting: meters and yards. Type XI - Scales, plotting: soil survey. Type XII - Scales, drafting: enlarging. Type XIII - Scales, drafting: metric proportional.

The shape of the scales shall be designated as follows (see figure 1):

1 - Two bevels, flat, opposite (parallelogram). 2 - Two bevels, flat, same side (trapezoid). 3 - Alternate shape, two bevels, composition G only. 4 - Four bevels (flattened hexagon or lozenge). 5 - Single bevel, flat. 6 - Six bevels, triangular, flat or regular. 7 - Six bevels, triangular, facet or concave.

The composition of the scales shall be as follows:

A - Wood with plastic facings (includes B). B - Wood with complete plastic coating except ends (excludes A). C - Plastic. D - Wood. E - Aluminum alloy (plastic coated). F - Aluminum alloy (anodized). G - Steel.

The grade of scale shall be designated as follows:

1 - High precision. 2 - Regular precision (to be supplied unless grade 1 is specified).

The size of the scales shall be designated as follows:

A - 10 inches. B - 12 inches/30 centimeters. C - 18 inches. D - 50 centimeters. E - 24 inches. F - 6 inches/15 centimeters (pocket) except that certain metric scales may be 10 centimeters.

The scale graduations shall be designated as follows (see figure 1):

1 - Fully divided. 2 - Open divided.

The numbering of the scales shall be designated as follows (see figure 1):

A - Direct numbering. B - Inverse numbering. C - Double numbering. D - Boustrophedon numbering. E - Single numbering.

The style shall be either the English or metric measurement system displayed as decimal, fractional, or ratios of the various units of measurement within each system. Styles shall be as specified in each specification sheet and shall be designated in alphabetic sequence.

Sheaths shall be designated as follows (see 3.8):

1 - Leather. 2 - Artificial leather. 3 - Heavy vinyl plastic. 4 - Heavy paper or plastic. 5 - Plastic or cloth-covered cardboard or calendered cardboard. 6 - None required.

intended Use: