2. Equipment and Materials
A. Teflon coating BMS 10-86.
NOTE: A laminar X-500 teflon coating kit, color W or G is available consisting of: Color W (White)
SPRAY BRUSH
Resin component 7-W-27 7-W-27FC
Hardener 10-C-81 10-C-81
Color G (Gray)
SPRAY BRUSH
Resin component 7-X-74 7-X-74FC
Hardener 10-C-81 10-C-81
B. Reducer (For color W and G) 66-C-28 and 66-C-20
C. Toluene - TT-T-548 (JAN-T-171, Grade A, optional)
D. Methyl Isobutyl Ketone - TT-M-268
E. Cleaning Solvent - General Purpose BMS 3-2, optional: Aliphatic Naphtha - TT-N-95
F. Cheese cloth
G. Solvent - Final Cleaning of Metal Prior to Painting (Series 84) (Ref AMM/SOPM 20-30-84)
H. Scotch Brite Sheet - Finishing Type A (containing aluminum oxide abrasive), Minnesota Mining and Manufacturing Company, Optional: Bear Tex Aluminum Oxide Abrasive Disks, Behr-Manning Company, Troy, New York
I. Alodine 1200S powder (American Chemical Paint Co., Niles, California) or Alocram 1200 (B.A.L.M.)
J. Stiff-bristle brush
K. Wooden or plastic scrapers, or sandpaper
L. Silicon carbide abrasive paper - 180 to 325 grit
M. Primer - BMS 10-79
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3. Surface Preparation
A. Unpainted Metal Surfaces
(1) Pretreat with Alodine 1200 and prime surfaces with BMS 10-79 primer (Ref 51-21-171, Decorative Paint System).
B. Previously Painted Surfaces
(1) Clean and reactivate per 51-21-51, Chemical and Solvent Resistant Finish (use Method 1 for epoxy primer films force dried).
C. Plastic Laminate Surfaces
(1) Prepare surfaces per 51-21-21, Prepaint Cleaning and Pretreatment.
4.
Deleted
5.
Mixing and Application of Abrasion-Resistant Teflon Finish (Spray Application)
A. The abrasion-resistant teflon coating is supplied in two component kits of resin component 7-W-27 for color W and 7-X-74 for color G, and hardener 10-C-81. If thinning is desired, use thinner-reducer 66-C-28.
B. Mask off those areas adjacent to the areas which are to be coated with abrasion resistant Teflon coating.
C. Mixing of the resin-pigment component should be by stirring only. (Shaking is not effective.)
D. Mix the coating as follows:
Spray Application (Parts by weight)
Resin Component 7-W-27 or 7-X-74 3
Hardener 10-C-81 1
E. Mix these two components together by stirring only; do not shake. If thinning is required, up to one part by volume 66-C-28 may be added. If thinner is added, thoroughly mix the thinner into the 3:1 mixture by stirring only; do not shake. Allow the mixed material to stand at least 5 minutes before use.
NOTE: Shaking will entrap air bubbles in the mixture producing an uneven coating.
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F. At a temperature of 70°F the mixed material has a usable pot life of about l-1/2 hours. The pot life of a mixed material decreases approximately half for every 20 degrees rise in temperature. Material whose pot life has expired shall be scrapped. Do not mix more materials than will be used during the time listed above. Clean equipment prior to expiration of pot life.
G. Spray apply enough coats of Teflon coating to achieve the required dry film thickness. Where extremely difficult or impossible to spray, use brush application. If no thickness is specified, apply 5 to 10 mils (0.005 to 0.010 inch). Apply four to five wet cross passes per coat. Allow solvent to flash off 5 to 10 minutes between coats.
H. Prior to handling, allow the coating to dry tack free (at least 2 hours at 70 (+ 5)°F). Allow a minimum cure of 12 hours at ambient conditions prior to outdoor exposure.
I. Prior to assembly or in-service use, allow the last coat to air dry one hour followed by curing under the time-temperature conditions given in figure 701.
F85319
Abrasion Resistant Finish Curing Conditions 500
51-21-81 Figure 701 Feb 15/73
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J. Feather all sharp paint edges by tapering with a hardwood stick, light sanding with 180 grit or finer, or spraying with paint thinned as required. Exercise caution when feathering to prevent damage to aluminum skins.
6. Mixing and Application of Abrasion Resistant Teflon Finish (Brush Application)
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