Where degreasing sits in the sequence
Where to buyAluminium is cleaned and treated in a fixed order: identify the metal, clean, strip if needed, remove corrosion, solvent clean, conversion coat, prime, seal, paint (AC par. 6-136 and 6-134). The finish guide has the order in one table. Degreasing decides whether the later coats stick.
Detergent (water-based) cleaners
What it is. Water-based chemicals called surfactants that surround dirt particles so they can be washed away (AC 43.13-1B par. 5-63a).
What it is for. General washing, grime and light oil before a solvent wipe or stripping.
How it is used. Mix as the maker says, rinse with clean water, and dry. The maker sets the dilution; the dilution calculator does the arithmetic.
Life and cure. No cure. Rinse so no film is left under a coating.
Safety. Follow the SDS. AC 43.13-1B par. 6-90 covers general chemical precautions.
Specification. Aircraft cleaners are approved by the aircraft maker; the AMM names them.
Equivalents. Not by name. Use the AMM-approved cleaner.
Solvent cleaners
What it is. Solvents dissolve oils, greases, waxes, sealants, paints and organic matter so they can be wiped away on a cloth (AC par. 5-63b).
What it is for. Final degrease before a conversion coat, primer or sealant. The AC asks for a surface that is water-break free (par. 6-136j, magnesium rework).
How it is used. Clean small areas at a time and wipe dry with a clean cloth before the solvent evaporates; keep the solvent supply clean (Flamemaster CS 3201 bulletin, surface preparation).
Life and cure. No cure.
Safety. Flammable solvents need ignition sources kept clear and equipment grounded (AC 6-90a(10) to (12)). Follow the SDS.
Specification. See the cleaning solvents page.
Equivalents. See the cleaning solvents page.
Alkaline cleaners and paint strippers
What it is. Alkaline cleaners are water solutions that remove contaminants by chemical action rather than dissolving them (AC par. 5-63c). Paint removers come as solvent, bond release and disintegrating types (par. 5-63d).
What it is for. Heavy soil on bare metal; stripping a finish before repair.
How it is used. Process the metal as the maker says, rinse thoroughly, deoxidize if needed and then conversion-coat. Henkel's process for its conversion coat is: clean, water rinse, deoxidize (heavily oxidized surfaces), water rinse, treat, water rinse, dry.
Life and cure. Rinse completely: residue under a coating spoils adhesion.
Safety. AC 43.13-1B par. 6-90a covers strippers, which are strong alkalies and acids: mix per the maker's instructions, keep clean water at hand, wear gloves and eye protection. Never add water to acid. Follow the SDS.
Specification. Aircraft strippers and cleaners: the SRM or finish maker names them.
Equivalents. Do not use a stripper on composites or magnesium without approved data.
Deoxidizers
What it is. Acid solutions that remove oxide from aluminium just before a conversion coat. Henkel's bulletin calls for one on heavily oxidized or corroded surfaces.
What it is for. The step between rinsing and conversion coating.
How it is used. Follow with a separate water rinse, then the conversion coat. Henkel says its representative recommends the deoxidizer for each shop.
Life and cure. Work promptly: AC 43.13-1B par. 6-136d(2)(e) wants the conversion coat applied immediately after corrosion removal and rinsing.
Safety. Acid: follow the SDS and AC 43.13-1B par. 6-90a(2): never add water to acid.
Specification. Not stated in the sources read.
Equivalents. Not by name; use what the finish process names.
Questions people actually ask
Is a degreaser the same as a solvent wipe?
Not always. A water-based detergent lifts soil in the wash; a solvent wipe dissolves oil and sealant residue. Many procedures use both in turn.
Why must the surface be water-break free?
The AC asks for a solvent clean that gives a water-break-free surface on magnesium rework; water that beads or splits on the metal shows oil still there.
Can I use a household degreaser?
Aircraft cleaners are named by the aircraft maker. Anything else needs approved data, because residue and attack on finishes and seals vary.
Limits — when NOT to use this
What the sources support, and no further.
- No product recommendation. Cleaner approvals come from the aircraft maker.
- No dilution ratios here: they belong to the cleaner's data sheet.
- AC par. 5-63 is written for penetrant inspection cleaners; we use its definitions of cleaner types only.
Where to buy
Distributors coming soon.
Sources
- FAA AC 43.13-1B CHG 1, Chapter 6 (corrosion control, safety precautions, finishes) — Pars. 6-90 (safety precautions), 6-134 to 6-136 (finish, conversion coat, 48 hour rule, fasteners), section 4 (corrosion preventive maintenance, MIL-C-16173 Grade 4); par. 5-63 (cleaner types).
- Henkel, Technical Data Sheet BONDERITE M-CR 1200S AERO (known as Alodine 1200S), November 2019 — QPL-81706, Class 1A and 3 under MIL-DTL-5541, bath make-up, pH, temperature, time, process steps, equipment.
- Flamemaster Corporation, Chem Seal CS 3201 Technical Bulletin — Two-part polysulfide: classes A and B, mixing, temperature effect on application life, hardness, adhesion.