Surface Roughness Scale for Surface Quality Control

SIMPLE  TO  USE

Place the MICROFINISH COMPARATOR  Surface Roughness Scale alongside your work piece. Slide the scale so that the rectangle with the surface roughness you want is adjacent to the piece you are examining. Compare by drawing the tip of the fingernail across each surface at right angles to the tool mark. The feel of the fingernail contact must be the same if the finishes are identical.

TERMINOLOGY

TYPE:
The specimens are electroformed replicas of original ground surfaces.

MATERIAL:
This MICROFINISH COMPARATOR Surface Roughness Scale is made of nickel. It will not corrode.

APPEARANCE:
Each specimen has the surface roughness characteristics of a ground metallic material.

SURFACE ROUGHNESS:
Means the finely spaced surface irregularities produced by the cutting action of the tool edges, the feed of the machine tool and by abrasive grains.

UNIFORMITY AND ACCURACY:
The original masters and the electroformed replica production masters have been checked at evenly distributed intervals. Sufficient measurements were taken to determine a representative average. The rating listed is the average of these readings.

LAY:
This is the term used to designate the direction of  predominant surface irregularities.

FLAWS:
These are the irregularities which may appear at infrequent intervals. They are not typical of a ground surface.

The G-62 MICROFINISH COMPARATOR Surface Roughness Scale is made by a dual electroforming process wherein nickel is electrodeposited to provide an exact reproduction in intricate detail. The same electroforming process used to produce the Surface Roughness Scale is available from GAR Electroforming to serve your product needs.

The surfaces used in this scale are reproductions of accurately ground surfaces measured in microinches (millionths of an inch - 0.000001"). The numbers engraved alongside each surface are the average deviation from the mean surface expressed in microinches.

The G-62 MICROFINISH COMPARATOR Surface Roughness Scale provides industry with established cylindrical roughness specimens for visual and tactual comparison. It is used in specifying and controlling surface roughness  when a product having the appearance of typically ground surfaces is  required.

The G-62 MICROFINISH COMPARATOR Surface Roughness Scale provides an economical tool which permits roughness to be specified on the same basis as linear measurements.  The surfaces presented are the result of years of research and engineering. Details covering this subject are now published in The American National Standards Institute (ANSI) specification titled: "Surface Texture, Surface Roughness, Waviness and Lay." ANSI/ASME B46.1

This MICROFINISH COMPARATOR Surface  Roughness Scale is a product of the engineering skill and precision workmanship of GAR Electroforming Division.