Vintage Rust Look Again

Discussion in 'Board Trackers and Vintage Motorized Bicycles' started by dogcatcher, Jun 20, 2017.

  1. dogcatcher

    dogcatcher Member

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    I have noticed that some of the Chinese engines have had a "patina" added to them to make them look like old cast iron engines. Being made out of aluminum, how is that look being done. I found a paint on method, but n my mind the heat generated by the engine would burn it off. Any help? Thanks.
     
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  2. indian22

    indian22 Well-Known Member

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    Paint developed specifically for engines or BBQ grills will not burn off due to engine heat actually most won't even cure hard until heated by the engine for prolonged periods. One paint color available is cast iron. Black paint on the jug only was quite common on all motos, but for an aged look flat black is a good place to start. Shiny is not something that screams it's old & neither is perfect...nicks, scrapes and rubs are what we expect with age. I see it each morning in the mirror, it's like a 15 year old kid showing up at a club with a perfect ID but for a 30 year old man. The plan was ok but the execution sucks.

    If you want to avoid painting a wire brush turned at high speed will roughen up, discolor & darken aluminum thus aging the metal. If that's not enough a mild "diluted" acid wash, as in plumbing and pool maintenance products, can be used to accelerate aluminum/metal corrosion. This is dangerous! If you are new to working with caustic chemicals educate yourself or better yet let a pro handle it. Fumes are highly toxic even in diluted solution. Mixing improperly can cause violent reactions and gloves, safety goggles/ face shield & respirator along with good ventilation is recommended, lastly avoid using acid on areas where gaskets or seals are used.

    Another technique is the use of an aluminum bluing and blackening product like "Casey's" available at gun shops or distributors. The metal has to be absolutely free from any form of oil or it won't take. I also use a heat gun to accelerate and improve the bond, hair dryer in a pinch for small parts. Bare iron or steel can be heated with a torch producing some extravagant "case colored hardening" colors, but without the hardening part. These are applied at relatively low temps and only start to show up during metal cooling at room temperature, no quenching.

    Burnishing on exposed areas especially edges where rubbing or wear might occur over time is also a technique that pro's use to fool even the experts on antique counterfeit metal. As is selective areas of metal "pitting" on exposed chrome or nickle parts(again using acid) on the artificial pin point pits to set in rust. New chrome or nickle luster is often dulled using varying grades of abrasive paper. Brass parts that were plated with nickle can be wear aged by careful hand sanding and finished with a dull polish.

    Lastly steel can be allowed to rust naturally or accelerated with acid. When the desired look is achieved an acid stop is used (baking soda solution) if acid was used, then washed and air dried. I let this set a few days or even weeks, then apply an automotive rust eater product that turns dark and forms interesting patterns on the steel. Over a period of months I reapply to any areas that are showing new rust these usually are just very small patch and it takes no metal prep just dab a little of the stop rust product to the area and forget it.

    It's all just good natured larceny technique unless you are actually trying to defraud others with new "barn finds", lot more metal aging tips are useful, but this should get you thinking...be careful with the chemicals even the "Casey's".

    Rick C.
     
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  3. dogcatcher

    dogcatcher Member

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    Thanks, I had not thought of Casey's, I have some, that I will attempt on the steel parts of the engine. Probably just paint the aluminum parts, and hit it later with a little rust colored paint. Thanks again.
     
  4. dogcatcher

    dogcatcher Member

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    A neighbor suggested using this to blacken the aluminum parts of the engine. https://www.caswellplating.com/meta...ng-solutions/aluminum-blackener-16-fl-oz.html

    Another neighbor suggested a light coat of old used motor oil and a few trips down a dirt road to coat it with the dust, then mist it again with the used motor oil and hit the dusty road again. Said a few coats will make the engine look older than us.

    That's what happens when you live in a neighborhood where 80% are retired... LOL
     
  5. indian22

    indian22 Well-Known Member

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    Yes I do understand neighbors and what you were told is correct...dirt & oil however reflect neglect, not just age. Lazy way to do something. & is not appealing to those who love old machinery and those who take pride in keeping mechanisms up and running. If you go with the oil method (forget the dirt) better results can be achieved by burning the oil off after applying to the metal with a propane torch, then let air cool and carefully clean off some of the residue to suit the look your're after. Don't overheat the metal, just set it afire without burning down the neighborhood. Some dis assembly is required as fuel in the engine case might explode and fragile seals & gaskets won't take much heat and flame. I'd suggest practicing on scrape aluminum with all the methods I've mentioned in both posts to get a feel for the results.. you won't get great results without some investment of time and energy. It's more art than science.

    The Caswell's aluminum black is basically the same as Casey's...not the blue product which is for steel, but the blackening formula for aluminum. Bluing & blacking are different terms & easily confused & the look both achieve are also quite different. Casey's also offers a black for brass product. Buy the correct product for the metal you are working with. I use all 3 products but not on the same metal. Also diluted muratic acid is what I typically use to set up corrosion on both copper, brass and aluminum. I neglected to state that in the first post.

    Probably more info than you can use but perhaps it might help someone achieve the look they are trying for. Rick C.
     
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