What are good alternatives to protect a raw aluminum finish without resorting to anodizing or clear powdercoating? Specifically, I'm going to have either a machined or brushed aluminum finish which I want to keep from staining or corroding. I was thinking of maybe melting on wax and then buffing it off.
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Protect Aluminum Surface Finish?
- Thread starter Zoltan
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Andre
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Yup, it'll stay put.
You can also use paste wax with Carnuba wax. I use one meant for floors, but I'm sure a car wax would work just as well.
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I use a Rustoleum clear enamel product on aluminum I do for the local hospital network. Seems to hold up well.
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I have used automotive clear coat
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Some ideas....
► For a new project... if you'll start with 3003 grade aluminum stock, it is naturally resistant to corrosion (even salt water) and 90% of your job will be complete before you even start. 3003 is one of the weaker grades of aluminum, but it is machinable and weldable. The bright, shiny traffic control cabinets you see at intersections are un-treated, un-coated, un-painted 3003 sheet metal, and they look great year after year. If you want to attach this part to steel, brass, or concrete where galvanic corrosion might possibly start, then simply separate the 2 materials with a sheet of plastic.
► For a restoration project... there is an inexpensive (non-electroplated) dip process for aluminum. Technically it is a chromate conversion process. It has industrial names like Iridite, but you can do the same thing at home with a couple of buckets and a product called Alodine. (Do a Google search.) First you de-oxidize the surface by sanding and submerging in a strong base, then rinse, then submerge in the Alodine, then rinse again, then blow dry. Typically aluminum parts turn some shade of yellow, but the yellowing is solely indicative of the time spent in the Alodine and grade of aluminum. A 10-15 second soak will leave your part nearly silver. The amount of yellow color is an indicator of the level of corrosion resistance, so nearly clear would be very light protection, but it is still superior to almost every other coating for aluminum.
Furthermore, the chromate conversion leaves the perfect surface to accept paint, or in your case clear lacquer. Combining the 2 would give superior protection. However, you also need to understand that Anodizing (which you mentioned) is a time-consuming electroplating process that goes INTO the surface, and therefore has very good scratch resistance. Chromate conversion is a coating on top of the surface, and is not a good wear surface. But due to the simplicity and 100% coverage answers most of the needs of most parts.
Hope this helps.
► For a new project... if you'll start with 3003 grade aluminum stock, it is naturally resistant to corrosion (even salt water) and 90% of your job will be complete before you even start. 3003 is one of the weaker grades of aluminum, but it is machinable and weldable. The bright, shiny traffic control cabinets you see at intersections are un-treated, un-coated, un-painted 3003 sheet metal, and they look great year after year. If you want to attach this part to steel, brass, or concrete where galvanic corrosion might possibly start, then simply separate the 2 materials with a sheet of plastic.
► For a restoration project... there is an inexpensive (non-electroplated) dip process for aluminum. Technically it is a chromate conversion process. It has industrial names like Iridite, but you can do the same thing at home with a couple of buckets and a product called Alodine. (Do a Google search.) First you de-oxidize the surface by sanding and submerging in a strong base, then rinse, then submerge in the Alodine, then rinse again, then blow dry. Typically aluminum parts turn some shade of yellow, but the yellowing is solely indicative of the time spent in the Alodine and grade of aluminum. A 10-15 second soak will leave your part nearly silver. The amount of yellow color is an indicator of the level of corrosion resistance, so nearly clear would be very light protection, but it is still superior to almost every other coating for aluminum.
Furthermore, the chromate conversion leaves the perfect surface to accept paint, or in your case clear lacquer. Combining the 2 would give superior protection. However, you also need to understand that Anodizing (which you mentioned) is a time-consuming electroplating process that goes INTO the surface, and therefore has very good scratch resistance. Chromate conversion is a coating on top of the surface, and is not a good wear surface. But due to the simplicity and 100% coverage answers most of the needs of most parts.
Hope this helps.
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I find if I polish Al with the polishing kit from Hf or Eastwood it last a verry long time. I made a shift knob for my hurst shifter in my mustang 5 years ago and polished it and it still has the mirror shine even with my sweety hands on it all the time.