MIL-PRF-23586F
4.7.4 Application life properties.
4.7.4.1 Pot life. Fifty grams ±5 grams of catalyzed compound shall be placed in a suitable
container so that a 0.5 ±0.5 inch thickness layer of compound is obtained. A micro-spatula shall
periodically be dipped well below the compound surface, slowly withdrawn and the stringy
compound observed. The length of time required for the strings to first break without stretching
more than approximately one inch shall be considered pot life.
4.7.4.2 Application time. Sufficient base compound and accelerator to fill a half pint container
(2-7/8 inches in diameter by 2-7/8 inches high) within ½ inch of the top shall be mixed at standard
conditions (see 4.4.1). The can shall be tightly covered except when determining viscosity. At the
end of the rated application time (see 3.3.1.5), measured from the start of mix, stir the mixed
compound for 1 minute with a glass rod, then determine the viscosity as specified in 4.7.3 using the
following spindles and speeds:
Type I - #2 spindle at 5 rpm
Type II - #6 spindle at 10 rpm
Type III - #2 spindle at 2 rpm
4.7.5 Hardness. Two specimens, 0.25 by 1 by 2 inches, shall be prepared in an open mold and
cured as specified in 4.6. After a 3-second application, hardness shall be determined in accordance
with ASTM-D2240, using the type A Durometer.
4.7.6 Tensile properties. Tensile strength and elongation shall be determined in accordance
with ASTM-D412 using specimens cut from die C. Specimens shall be cut from molded sheets
approximately 0.075 inch thick, prepared and cured as specified in 4.6.
4.7.7 Linear shrinkage. Linear shrinkage shall be determined by curing mixed compound in a
6 by 6 by 0.075 inch mold filled to capacity and cured as specified in 4.6. The molded sheet shall
be measured using a ruler with 0.01-inch divisions. Shrinkage shall be calculated as follows:
6 inch - molded slab measurement (inch)
Percent Shrinkage =
x 100
6 inches
4.7.8 Specific gravity. Three specimens, 0.075 by 1 by 2 inches, shall be cured as specified in
4.6. The specimens shall be weighed in air and then in water by means of an analytical or Jolly
balance. The specific gravity shall be computed as follows:
Weight in air
Specific Gravity =
Weight in air - Weight in water
12
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business