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Seat Structure and Components Command philosophy varies regarding the painted parts of a seat structure. Some squadrons strip and paint at each 210-and 364-day inspection. Some leave the original anodized finish unpainted. Some touch-up chipped paint. Some do nothing. Each of these philosophies has some merit depending upon local conditions. The seat bucket and beam structure should be wiped with VV-L-800 general-purpose oil. You should allow the oil to soak into crevices, around rivets, and then wipe dry. Clean metal components with P-D-680, Type II, dry-cleaning solvent, and then inspect them for surface damage and corrosion. Do not attempt to remove light corrosion or discoloration of the cadmium-plated parts. Parts showing rust or pitting of the base metal or more than one area of plating loss should be replaced. Remove light corrosion, except for cadmium plated parts, by using a fine Scotchbrite abrasive mat or 500/ 600 aluminum oxide abrasive cloth. Lubricate moving parts, such as springs, linkage, and pivot areas, with MIL-G-81322 general-purpose grease. Lubricate firing pins and rollers with VV-L-800 oil. When using VV-L-800 oil, you should apply it with a clean, lint-free cloth such as MIL-C- 85043. Indiscriminate use of paint, preservatives, or other materials that dry and buildup following application can prevent or restrict proper motion of movable parts. These materials must only be used where specified on nonmoving parts. Paint touch-ups of seats installed on the aircraft should be done with a brush. The following paragraphs provide guidelines for removal of corrosion products without damaging the structure. Removal of corrosion that has propagated beyond these limits requires replacement of the part. CADMIUM-PLATED PARTS.- On cad-mium-plated parts, corrosion will be evident as mottling of the plated surface with color ranging from light gray to black. This is a function of the cadmium plating to protect the underlying base metal, and no attempt should be made to remove the discoloration. The presence of exposed base metal in a localized area is acceptable and should be protected. The appearance of red rust is cause for part replacement. CHROMIUM AND NICKEL-PLATED PARTS.- You should polish bright plated parts with a fine Scotchbrite abrasive mat or 500/ 600 aluminum oxide abrasive cloth. Do not penetrate to the base material. If base material is exposed, it is cause to remove and replace the affected part. ALUMINUM FORGINGS AND CAST-INGS.- Metal removal should not exceed 0.005 inch in depth. You should apply chemical conversion coating (alodine) to bare surfaces and repaint them as required. RESTORATION OF FINISH Abrasions and isolated damage areas may be restored using the following procedures: First, mask the area to be treated. You should feather sand the area around the damage with abrasive paper or Scotchbrite mat. Next, apply paint remover or methyl ethyl ketone and wipe the area dry with cheesecloth before the solvent evaporates. At this point, if bare metal is show-ing, you should apply alodine and allow it to dry. Finally, apply one coat of primer and two coats of paint. Special attention should be paid to the use of primers, polyurethane paints, paint removers, and methyl ethyl ketone. They are all flammable and toxic. Do not use them near open flames or sparks. Do not allow them to come in contact with your skin or eyes. Their use should be restricted to a well-ventilated area. SAFETY PRECAUTIONS Safety precautions must be strictly observed when working around aircraft equipped with an ejection seat. These safety precautions cannot be overemphasized. Each ejection seat has several ground safety pins. These safety pins are provided on red-flagged lanyards for use at every point of potential danger. They must be installed whenever the aircraft is on the ground or deck, and they must never be removed until the aircraft is ready for flight. The following general precautions should always be kept in mind: 1. Ejection seats must be treated with the same respect as a loaded gun. 2. Always consider an ejection seat system as loaded and armed. 3. Before you enter a cockpit, know where the ejection seat safety pins are located and make certain of their installation. 4. Only authorized personnel may work on, remove, or install ejection seats and components, and only in authorized areas. Supervisors take note. It has been said that nothing is foolproof because fools are so ingenious. Personal safety for those who work around ejection seats cannot be guaranteed; however, a high level of safety can be achieved if personnel have the proper attitude, under-standing training, and adequate supervision. Unless proper maintenance procedures are followed explicitly, even the most routine ejection seat maintenance tasks can grow drastically out of proportion and bring about an accident or injury. Education of the workers involved is the best assurance for personnel safety. The workers should be made aware of potential hazards and the proper means of protecting themselves. Workers should be assigned according to their capabilities.
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