If you want to age, gray or "weather" new wood to create a quick "shabby chic" finish or to match older finished and weathered projects, including furniture, decks, and fences, this easy technique with vinegar and iron oxide is easy and effective.
Although you can create these same effects with pre-mixed paints and stains, new wood can be aged in minutes with a simple easy-to-use solution of household materials that can be painted on. The technique is variable depending on the type of wood being used.
This information was designed for modelers and miniaturists, but the technique works just as well on full-size fences, furniture, or shabby chic building projects. With a simple vinegar/iron oxide (rust) solution you can color wood to a weathered silver color or darker.
Wood Aging Solution Based on Vinegar
To age new wood to a natural silvery gray, to grey-brown or black patina (depending on the wood), let a small piece of steel wool (or a few non-galvanized nails) sit overnight in ordinary white vinegar, then dilute the vinegar solution 1 to 1 with water. (If you used 1/4 cup of vinegar, add 1/4 cup of water.)
The nails or steel wool will have rusted. Test the result by brushing the solution on a piece of scrap wood the same as you will be using, to determine if the aged finish is the correct color. On most wood, you will begin to see the aging effect as soon as the solution is dry If not, for darker solutions, leave the solution to sit longer, or add a bit more vinegar, and test it again.
Do not paint this on the final wood before you make a test in a low visibility area. The solution will need to be stronger or weaker to match age effects on certain woods.
Adjusting the "Aging" Solution Color
Solutions which are too strong produce very dark coloration. They will need more water added to dilute them before you test again. When the solution produces the desired effect, brush it over fresh wood to create an instant greyed patina once the solution is dry.
This is a great way to create barn boards. You also can use this technique on balsa wood roughened with a wire brush to create a thatched effect, or to create weathered shingles or fence posts.
Other Aging Effects for Wood
Many other aging effects for wood finishes involve rubbing patinas into paint, or layering paint to produce an aged effect with an overlay of colored furniture wax (you can use dark brown shoe polish). You can easily make your own chalk or limewash style paints for custom colors to give you the same effect.
Tips On Aging Wood With a Vinegar - Iron Oxide Solution
This finish varies with the type of raw wood it is applied to, the roughness of the wood, (rough wood absorbs the solution more readily) and the strength of the solution. Balsa and basswood will turn gray or dark brown (depending on the solution strength). Oak will blacken.
The high acid level of the finish means this is not a recommended finish for high-quality miniature furniture or pieces for sealed display cabinets, but the acid effect can be sealed beneath a coat of matte acrylic varnish which will help keep it from affecting fabric and other items close to the acidic finish.
Depending on your application you could also try buffering sprays to neutralize the pH of the vinegar wood stain if you do not want to seal the finish.
The finish will not penetrate glue, so ensure that pieces to be aged have been carefully wiped after gluing to keep glue from the surface, or age sections of your project before you glue them. If areas will not stain, use washes of acrylic paints to age the area with instead of the vinegar/steel wool solution.