ASTM F428-83(1997)e1

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
e1
Designation: F 428 – 83 (Reapproved 1997)
Standard Test Method for
Intensity of Scratches on Aerospace Glass Enclosures
This standard is issued under the fixed designation F 428; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
e NOTE—Sections 9 and 10 were added editorially in April 1997.
1. Scope inside surface. The lightest scratch is identified as ASTM F
428-2 and the heaviest as ASTM F 428-8.
1.1 This test method covers the visual inspection of
scratches on the glass surface of aerospace transparent enclo-
6. Procedure
sures.
6.1 Place the part in a suitable inspection position. This may
1.2 This standard may involve hazardous materials, opera-
be horizontal on a padded table, vertical against a neutral
tions, and equipment. This standard does not purport to
background, or at an angle simulating the installed position.
address all of the safety concerns, if any, associated with its
The scratched surface shall be toward the observer. The light
use. It is the responsibility of the user of this standard to
level shall be a minimum of 80 lumens. Either natural or
establish appropriate safety and health practices and deter-
artificial light may be used. Place the scratch in the visual
mine the applicability of regulatory limitations prior to use.
comparison standard beside and parallel to the scratch in
2. Referenced Documents question. Rotate the part or viewing angle to get the best
2 definition of the scratch. Disregarding the length of the scratch
2.1 ASTM Adjuncts:
on the part and on the standard, select and record the standard
Scratch Test Standard (Glass) Adjunct F 428
that most closely matches the appearance of the scratch on the
3. Summary of Test Method
part. Measure and record the length of the scratch to the nearest
1 mm (or 0.05 in.).
3.1 A visual comparison is made between a set of graded
scratch standards and the scratch on the glass aerospace
7. Interpretation
transparency to determine the relative intensity of the scratch.
7.1 Customer specifications for aerospace glass surfaced
4. Significance and Use
transparent enclosures may detail allowable frequency, loca-
tion, length, and standard number for scratches and they may
4.1 Scratches exist on all glass surfaces. Usually they are
assign maximum scratch limits for critical and noncritical
very fine scratches from cleaning operations that are not visible
optical viewing areas.
when looking through the glass. Visible scratches may be
distracting to the observer looking through the enclosure.
8. Report
Therefore, a proced
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