(10)
G00238 Gauze - Clean
(11)
G00034 Cheesecloth - Clean and Lint-Free
(12)
G00115 Polyethylene Sheet
(13)
G00253 Paper - Greaseproof
(14)
G00257 Paper - Laminated Waterproof
(15)
G00217 Sponge
C. Procedure - Apply Conversion Coating
S 127-002
WARNING:_______MAGNESIUM POWDER CAN CAUSE A FIRE. DAMAGE TO EQUIPMENT OR INJURY TO PERSONS CAN OCCUR.
(1) Rub the edge of the finish with abrasive paper (240 grit maximum).
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S 167-004
(2) Clean the surface as follows.
(a) Remove all loose particles from the surface with a soft-bristle brush or rub the surface with a clean gauze.
CAUTION: PROTECT ALL SURFACES THAT YOU DO NOT WANT TO CLEAN.
_______
CLEANER CAN DAMAGE FINISH, CADIUM AND ALUMINUM.
(b)
Apply protection to all areas that you do not want to clean. Use a material that will resist water. For example, use polyethylene sheet, greaseproof paper, or laminated waterproof paper.
(c)
To prepare the cleaning solution, mix 10 volumes of water to 1 volume of Kelite 28.
CAUTION: DO NOT ALLOW THE CLEANING SOLUTION TO STAY IN FAYING
_______ SURFACES. DAMAGE TO THE FAYING SURFACES CAN OCCUR IF YOU PERMIT THE CLEANING SOLUTION TO STAY ON THE SURFACE.
(d) Apply the cleaning solution to the surface using a cloth, brush, or a sponge. Let the solution soak for 5 minutes.
NOTE: Do not permit the cleaner to dry on the surface.
____
(e)
Flush the surface with a clean wet cloth or a sponge. Flush the surface a minimum of two times.
(f)
Flush the surface with water until you get a water break-free surface.
NOTE: A water break-free surface will have a continuous layer
____
of water for 30 seconds.
(g) Clean the surface with a mixture of magnesium oxide and water to remove the water break. Dry the surface with a clean gauze and do step (e) again.
S 377-005
(3) Mix the Dow 19 conversion coating as follows.
(a) In a clean 1 gallon glass or polyethylene container:
-
add 9/10 gallon water
-
add 1 1/3 ounce chromic acid
-
add 1 ounce calcium sulfate powder
-
add water to fill the container to the 1 gallon level.
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MAINTENANCE MANUAL
(b) Mix the solution for a minimum of 15 minutes. Let particles in the solution go to the bottom of the container.
NOTE: The solution must be free of all particles when it is
____
applied.
(c) Measure the pH of the solution. The pH must be from 1.2 to
1.6. Use sulfuric acid to lower the pH or use sodium hydroxide to increase the pH.
S 377-006
CAUTION:_______DO NOT USE FORCE TO RUB THE WET SURFACE. TOO MUCH FORCE CAN CAUSE DAMAGE TO THE COATING.
(4) Apply the conversion coating solution:
(a) Apply a large quantity of solution to the metal surface until the metal surface is gold to dark brown in color.
CAUTION: HIGH PRESSURE WATER SPRAY, RUBBING ABRASION, OR HIGH
_______ PRESSURE AIR BLAST CAN CAUSE DAMAGE TO THE NEW COATING.
(b)
Flush the surface with clean cold water.
(c)
Dry the surface with air at a maximum temperature of 180°F.
(d)
Make sure all of the surface is coated.
(e)
Make sure that there are no scratches, powder or lines on the surface.
(f)
To remove the powder, rub the surface with a clean cloth and apply the conversion coating again.
S 377-007
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