weathering corrugated aluminum

Discussion in 'Weathering Forum' started by eric halpin, Apr 2, 2008.

  1. eric halpin

    eric halpin Eric Halpin

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    I have just added for the first time to a track-side structure, the aforementioned roofing material. It looks good but now I want to weather it to give it a rusty/sooty appearance. How would you recommend I proceed to achieve that look. Thanks.

    Eric
  2. RonP

    RonP Member of the WMRC

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    The best way is circuit board etching solution it breaks the metal down literally. I can't find it so i am using acrylic paint and weathering chalks. The colours i use is burnt umber, burnt sienna, and other orangy and browny combinations.

    Etching is easiest.
  3. Jim Krause

    Jim Krause Active Member

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    Campbell Scale Models recommends spraying their aluminum corrugated roofing with dull coat as a primer, followed by concrete grey paint then rust color. I used this method and it works well but requires some practice to get the desired effect without going overboard.
  4. MasonJar

    MasonJar It's not rocket surgery

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    I like the DullCote + acrylic (craft) paints applied with a drybruch technique. You can also use chalks for a really rusty look. If the metal is to be rusted completely away, try the etching solution, but be prepared to stop it quickly, as it can eat away very fine siding in an instant...!

    Andrew
  5. Fluesheet

    Fluesheet Member

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    There was an article that touched on this in the March Model Railroader and I believe that they used an etching solution like RonP suggested. Possibly they mentioned a source. I'll take a look this evening.
  6. doctorwayne

    doctorwayne Active Member

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    The etching process does a great job of replicating rusted and rusted-out sheets, but for sheets just starting to rust, airbrushing and/or dry brushing works well, and for more well-rusted sheets, chalks can add a three-dimensional effect.

    Wayne
  7. eric halpin

    eric halpin Eric Halpin

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    Good suggestions fellas. I shall try the dullcoat and dry brush method first.

    Eric
  8. Fluesheet

    Fluesheet Member

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    The article only refers to "circuit board etchant". No brand or source.

    By the way, the article was the first I'd heard of this - what is the visual result of using etchant?
  9. doctorwayne

    doctorwayne Active Member

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    The circuit board etchant that I know of was by Archer, I believe, and was available through Radio Shack. The effect looks great, but I'm told that you have to watch the process closely, as there's a point when the sheet begins to be eaten away completely.
    I would think that any acid would have a similar effect: if the weather would warm up a bit, I'd go out and try a few different ones in the garage.

    Wayne
  10. RonP

    RonP Member of the WMRC

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    Radio shack stopped making the etchant. There is a simple recipe I seen somewhere when I get time I'll find it for y'all. Only place I have found it available is online electronics dealers. Please post your finding here. As i have seen this stuff in action and it does work just like real life at high speed.
  11. doctorwayne

    doctorwayne Active Member

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    Here's a link: Sayal Electronics . Check under "Chemicals" - there are several listed.

    For those in southern Ontario, they have an outlet in Burlington. It seems to me that there are or were some sort of regulations governing shipping this stuff, though.

    Wayne
  12. RonP

    RonP Member of the WMRC

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    I heard there wasn't a problem although you'd think there would be. Best to email/call to check first.
  13. MasonJar

    MasonJar It's not rocket surgery

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    This brings to mind the Grade 8 Science Fair, where kids would remove rust from nails using Coca-Cola... It took a month, but it was an interesting experiment. I wonder what vinegar, Coke, or any other household acid would do to the corrugated roofing materials?

    Andrew
  14. railBuilderdhd

    railBuilderdhd Member

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    I've herd of others using vinegar but you need to keep it in an open container for oxidation to occur.
  15. Dave Harris

    Dave Harris Member

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    A very effective method is to spread a light film of olive oil on the sheet, then hold it over a flame ( gas stove works well) till the olive oil begins to smoke & turn shades of brown. It does not take long & a little practice will yield great results.
  16. Dave Harris

    Dave Harris Member

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    Here are a couple of pictures of weathered corrugated aluminum, using two different methods. The door was done with the olive oil treatment, the window covering was the ferric chloride etchant ( circut board)

    Attached Files:

  17. Gary Pfeil

    Gary Pfeil Active Member

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    The corrugated roofing on this Campbell kit was painted a grey, I believe it may have been UP harbor mist grey or some such. Then it was drybrushed with several shades of rust.

    [​IMG]