Powder-coated aluminium
A baked organic coating over metal. Strong solvents and abrasives attack the coating, and the rule of thumb for what is mild enough is unusually memorable.
In detail
Powder coating covers aluminium with a thermoplastic or thermosetting organic film, baked on, and it is what most modern window frames, garden furniture, radiators and appliance panels are finished with. Because the finish is a polymer rather than an oxide, its failure mode is different from anodising's: strong solvents and abrasive cleaners damage painted surfaces, and excessive abrasive rubbing produces an appearance change even where nothing is visibly scratched. A standards body's escalation for it is deliberately low and worth following in order — flush with water at moderate pressure to dislodge soil; if soil still adheres use a mild detergent with brushing or sponging under uniform pressure; rinse thoroughly; and dry with a chamois, squeegee or lint-free cloth rather than leaving it to air dry in place. Its rule of thumb for what counts as mild is the most quotable line in the document: a soap or detergent judged safe for bare hands should be safe for coated aluminium, and anything stronger must be spot tested carefully. Two standing instructions apply as much here as on anodising: identify the finish before choosing a method, and never clean a hot, sun-heated surface.
Properties
Sensitivity
- Acids
- Sensitive
- Alkalis
- Sensitive
- Chlorine bleach
- Not known
- Heat
- Sensitive
- Abrasion
- Sensitive
- Porous
- Not applicable
“Not known” means nobody has established this, not that the material is unaffected.
What works
Soap is safe on, in specific conditions, Powder-coated aluminium
Safe only in specific conditions
This is only appropriate within specific limits, and nothing is established outside them.
Only within these limits:
- Mild dish soap, or a fifty-fifty water and vinegar solution
- No abrasive cleaners and no solvents
- Blot dry with a dabbing action rather than rubbing
The one finish in this manufacturer's document where vinegar is affirmatively permitted. Allowing water to evaporate on a metal finish forms deposits, which is why the drying instruction is a technique rather than a step.
Precautions
- Test on an inconspicuous area first
Evidence
Supported
Sources
KALLISTA (Kohler Co.) · Manufacturer documentation
Relied on for: That matte black and other powder coats may be cleaned with mild dish soap or a fifty-fifty water and vinegar solution, that abrasive cleaners and solvents are excluded across finishes, and that allowing water to evaporate on metal forms deposits so the surface should be blotted dry with a dabbing action. (states this directly)
Why
- Powder-coated aluminium is explained by Solvents and polymers
- Powder-coated aluminium is explained by Mechanical action and abrasion
Related
- Powder-coated aluminium is commonly affected by Algae
- Powder-coated aluminium is commonly affected by Dust
- Powder-coated aluminium is commonly affected by Moss and lichen
Hacks and claims involving this
- Acidic wheel cleaner on alloy wheels Disputed
Sources for this page
Sources
AAMA 609 & 610-02: Cleaning and Maintenance Guide for Architecturally Finished Aluminum
American Architectural Manufacturers Association (AAMA), 2002 · Standards body
Relied on for: That the guide covers thermoplastic and thermosetting organic coatings on aluminium, that strong solvents and abrasive cleaners can damage painted surfaces, that excessive abrasive rubbing adversely affects the finish, that the escalation is water then mild detergent then rinse and dry, and that detergents safe for bare hands should be safe for coated aluminium. (states this directly)