ENSTROM F-28F/280F SERIES MAINTENANCE MANUAL
Rev.
7
MM-9-75
Aug
22/16
WARNING
Use the proper protective equipment when working with the chemical
conversion coating. Observe the precautionary information and
instructions provided with the chemical conversion coating.
F. Treat the blade as required with a chemical conversion coating complying with MIL-
DTL-5541/MIL-DTL-81706.
G. Wipe the blade with Extreme Simple Green, or equivalent using clean rags.
NOTE
Do not paint the drag link mating surface of the drag link fittings.
H. Apply DeSoto Epoxy Polyamide Primer 513 X 390 (MIL-PRF-23377) or other suitable
epoxy primer as follows:
NOTE
Apply the primer in thin, even coats.
NOTE
It is important that the trailing edges of the main and tail rotor blades have good
coverage.
(1) Apply two coats to the spar and feather the coats past the spar to skin bond
lines. Apply two coats to the trailing edge straight on. Apply the third coat to the
whole blade.
(2) The application is the same for the tail rotor blades except that the whole blade
gets all three coats.
I.
Paint the finish coat with any good quality flat or satin finish polyurethane paint.
CAUTION
Refinishing main rotor blades will require retracking the main rotor system. The
rotor system may also be dynamically balanced using a Chadwick Balancing
System.
CAUTION
Tip weight changes must be made to keep 75% of the blade tip weight in the
forward pocket to maintain the cordwise balance.
CAUTION
Refinished tail rotor blades will be required to be statically and dynamically
rebalanced.
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