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|  MIL-M-48245B(AR)
4.4.3 Testing. Testing is described in First Article testing
and Quality Conformance Inspection Tables.
4.4.4 Inspection equipment. The inspection equipment required
to perform the examinations and tests prescribed herein is described
in the "Paragraph Reference/Inspection Method" column in the tables
starting with 4.4.2.1. The contractor shall submit for approval
inspection equipment designs in accordance with the terms of the
See Section 6 of MIL-A-48078.
contract.
(See 6.5)
4.5 Methods of inspection.
4.5.1 Base resin viscosity. Base resin viscosity shall be
determined using a Brookfield RVF Helipath viscosimeter with a T - f
spindle at a speed of 4 rpm. The viscosity reading shall be made at
the tenth revolution of the spindle.
4.5.2 Hardener viscosity.
Hardener viscosity shall be
determined using a Brookfield RVF Helipath viscosimeter with a T - F
spindle at a speed of 10 rpm. The viscosity reading shall be made
at the tenth revolution of the spindle.
Molding com pound properties - immediately after mixing.
4.5.3
Immediately prior to mixing, the base
4.5.3.1 Compound mixing.
resin container shall be agitated on a paint shaker for 45 minutes
minimum and the hardener container shall be agitated on the shaker
for 30 minutes minimum. The mixed molding compound for use in
determining conformance to Table I shall be prepared by thoroughly
mixing two (2) parts 5% by weight of the base resin with one (1)
part 5% by weight of hardener for not more than five (5) minutes,
and immediately degassing at an absolute pressure of 2 to 4 torr for
The mix shall be
3 1 minutes at a temperature of 150 10F.
used in testing for the requirements of Table I within 5 minutes
after mixing.
4.5.3.2 Viscosity of molding Compo und. The viscosity of each
lot of molding compound shall be determined on material mixed and
degassed as specified in 4.5.3.1 except that the material shall be
mixed at room temperature. Viscosity-shall be determined by using a
Brookfield RVF Helipath viscosimeter with a T-F spindle at a speed
at 10 rpm, at a temperature of 75 to 80F. The viscosity shall
be recorded after 10 revolutions of the spindle.
Three (3) viscosity measurements shall be made on each batch.
If the average value of the three viscosity readings fails to comply
with the value specified in Table I the molding compound shall be
rejected.
4.5.3.3 Gel time. Gel time shall be determined on a batch of
compound mixed and degassed as specified in 4.5.3.1. Gel time shall
be determined using the methods and procedures specified in
ASTM-D-2471.
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