On the other hand, metallic paints have come along way since then and have drastically improved in regards to finish, yielding realistic chrome-like properties. These days, there are oodles and oodles of metallic paints to choose from without breaking the bank on some fancy chrome spray paint system or having to go to a professional paint store to have it custom mixed. For less than five bucks a can, these metal paints are available from the spray paint section of your local home store, not to mention that they've become a lot bigger compared to twenty years ago.
I must mention that there are a few paints that stand out in the open and have yielded exceptional finishes: Valspar's Silver #66010 and Rust-Oleum Chrome #7718, in my opinion, have finishes that come really close to the brilliance of metal.
Problem: There are two major drawbacks with these two paints, especially if a builder is going for the A New Hope -throne room sequence R2-D2, where he is absolutely clean, pristine and his dome is buffed to a high shine! For one, the shiny finishes will be ruined once touched by human hands. Based on what a rep from the Rust-Oleum support department had responded in an email, the secret to these paints giving off its metallic reflective finish is the very fine leafing agents that are dusted onto the surface when sprayed. At the microscopic level, this "dust" forms peaks and valleys on the surface that allow light to bounce off at different angles, which gives us the brilliance of "chrome." Unfortunately, once this dust is rubbed off or the peaks and valleys are flattened, the result is a dulled appearance. We must consider that R2-D2's dome has a large surface area and will be prone fingerprints galore during public events. What's more disturbing, once a dome with this type of paint is touched by a child's hands, the paint also ends up sticking to them, embedded within the skin. -UNACCEPTABLE.
Along the same lines, the second major drawback is that when the chrome paint is top-coated with a clear paint, it ruins the finish. As mentioned, because chrome-like reflections highly depend on a layer of microscopic peaks and valleys, adding a clear coat fills and covers these formations creating a flattened surface, giving way to a dulled appearance. The bottom line: Using a clear coat to stop these paints from rubbing off while protecting and preserving its brilliance is not possible.
It is interesting to note that water-based and oil-based clear paints have different effects when applied over the chrome paints. From a few tests that I've done, an oil-based spray, such as Rust-Oleum Crystal Clear#7701, resulted in a dull, muddy darkened appearance and using a water-based clear ( I forgot the brand name), dulled it from a shiny chrome appearance to a standard bright silver color. Explaining these huge differences in effects may refer back to the fundamental rule in high school chemistry that "like dissolves like." Since an oil-based paint (Rust-Oleum Clear) is sprayed over an oil based paint (Rust-Oleum Chrome), which both are non-polar substances, the clear paint will dissolve the chrome paint. On the other hand, a water based paint should not dissolve the oil-based, since one is polar and the other is not. Okay, so I'll stop right here before I really go off on a tangent.
THERE'S STILL...HOPE. Realistically, aluminum isn't always shiny, as it can also appear with a dull gray finish, indicating being aged and oxidized. Many builders, including myself, with non-metal domes have gone to replicate this look with the ability to use a protective clear coat. As discussed, since using a clear coat over a chrome paint can "ruin" the finish in different ways, depending on which type of clear paint is used. This can serve as a great idea after all, giving the appearance of a dirty, oxidized look, given you use an oil based clear. This is a great alternative, provided you "weather" the rest of the droid to match and from what I have seen, going this route yields more convincing results, as opposed to replicating polished aluminum. ...so say goodbye to the Throne Room scene and say hello to the murky swamps of Dagobah! ...well not for me, as I wanted an oxidized look, but not so grimy. For my dome, I plan to simply use a basic silver paint, topped with Rust-Oleum Crystal Clear.
Which metallic paint to use?
As I've mentioned, the dreaded part of this project was choosing which paint to use for the dome! All silver metallic paints have their pros and cons, so I created a few guidelines to help narrow my selections down:
Project Astromech Dome Paint Criteria
1. Finish is 0% affected by the addition of a clear coat.
2. Will not rub off on your fingers.
3. Not too sparkly/ glittery (no large metallic particles or flakes)
4. Durable hard finish (wont easily dent).
5. Can be wet sanded and polished.
6. High performance spray: Not easily prone to runs or drips.
7. Mirror/Reflective finish.
8. Yields a uniform bright silver color.
9. Does not take months to cure.
10. Inexpensive and available locally.
The Paint Test
Purpose: To find the best dome paint, according to the above criteria, appropriate for a slightly weathered R2D2.
Researching through numerous articles, blogs, and forums on the net, and following the above criteria, it allowed me to narrow down a humongous selection of different paints to four:
Researching through numerous articles, blogs, and forums on the net, and following the above criteria, it allowed me to narrow down a humongous selection of different paints to four:
Procedure: Outdoors, and in the sun, each of the soda cans were quickly sprayed with one heavy coat of paint with a distance of six inches between it and and the spray nozzle. The temperature was about 88 degrees and the humidy was about 60%. No clear coat was used.
Results: I have included Valspar's Silver #66010 and Rust-Oleum Chrome #7718 despite its drawbacks (discussed above) because I wanted to use them for the purposes of comparison. Rust-Oleum and Valspar (exclusive at Lowe's) gave the best looking finishes, but the Rust-Oleum was hard to work with as you can see it had more drips and runs. The Valspar paint looked the most beautiful of the four and performed the best as it produced no runs or drips. As discussed earlier, both these products cannot be clear-coated without ruining the finish and this was not the look I was going for. The Krylon Bright Silver #1401 (a special order from ACE Hardware) can accept a clear coat but was too glittery to my taste.The Duplicolor Radiant Silver #BCC0338 (from Pep Boys) is actually a touch-up automotive paint that is designed to accept a clear coat and wasn't as sparkly as the Krylon, and according to my criteria for an ideal paint, this was a good thing. If the Duplicolor is durable for an automobile then I think it's okay to say its plenty durable for R2-D2.
...and the winner is:
Duplicolor Radiant Silver #BCC0338
The inner and outer styrene dome was painted with Rust-Oleum White Primer #249058, followed by two coats of the Duplicolor Radiant Silver and topped with two coats of Rustoleum Crystal Clear#7701.
...and the same went for the dome ring.
...and the same went for the dome ring.
After the paint was allowed to cure for a few days, it was not as glossy as I've wanted it and the surface felt a bit gritty. I improved the finish with a little buffing and polishing which was accomplished by rubbing folded pieces of standard copy paper on the dome in light circular motions. The paper acts as an extremely fine sandpaper, resurfacing the clear coat without introducing unsightly scratches. The dome was then cleaned and buffed using a microfiber towel. In the end, I was happy with the results which gave way to a more glossy, smooth, and reflective finish.
Next up: ARTOO STANDS!
Next up: ARTOO STANDS!
