How To Rust Galvanized Metal
Want to dull the finish of your shiny new galvanized pail? There are two options:
Let nature age it
Yes, you can allow the galvanized steel to weather naturally. New galvanized steel has a bright shiny coating and a reflectivity over 70%. As the zinc patina forms, reflectivity decreases as the hot-dip galvanized coating weathers. After 72 hours reflectivity drops to about 55%. After two years reflectivity is about 28% (9).
As discussed, if you want your galvanized rustic antique right away, there are several ways to make a new galvanized tub look like it has been around for a while. Vinegar acts much like the acid Sulphur Dioxide (SO2) does in the atmosphere; the pollutant that determines the rate of galvanized steel corrosion. Check out the infographic below to see the science of an acid corrosion reaction with vinegar.
If the idea is to remove the shiny look and go for a dull, weathered finish: Try Vinegar! Take the galvanized product and scuff it up sandpaper, steel wool or whatever abrasive you have handy. Submerge the product in vinegar. If the piece to be dulled is too large to be submerged, put the vinegar in a spray bottle, or soak paper towels in vinegar and lay them on the galvanized metal. If using the paper towel method, make sure to replace the vinegar as it dries to get the desired effect. If the metal still doesn't oxidize, try scrubbing with the abrasive again and repeating the process.
After soaking a new galvanized metal bucket in vinegar FOR ONLY 30 MINUTES (middle photo above), the last photo (right) above shows what it looks like.
If you are looking for a more distressed look, try toilet bowl cleaner. Use steel wool to rough-up the finish to allow the chemical to tarnish the metal. Using disposable gloves spray the galvanized product liberally and scrub again with the steel wool. Let the product sit for about half an hour or until the desired look is obtained. Rinse the product to halt the corrosion process. Please dispose this water responsibly.
We tied the bucket inside a bag for 30 minutes. The photo on the left shows what the galvanized metal buckets looks like distressed with toilet cleaner.
Salt also corrodes the galvanized zinc coating.
To corrode new galvanized buckets yourself:
Combine 1/2 cup of salt with 1 quart of warm water. Pour the mixture into a spray bottle and shake it until the salt dissolves. Spray this solution all over the outside of the galvanized bucket or tub. This will remove the shiny coating and give it a weathered look. Leave the salt solution on the bucket until you achieve the look you want, then rinse it off with a hose. Allow the bucket to air dry.
Antique Milk Paint
If chemical weathering isn't your cup of tea, try using a painting method instead. Using either gray or white paint to give the bucket a weathered look is an excellent idea. Using sandpaper, buff the galvanized product to remove the sheen and then remove the remaining dust with a cloth. Mix regular paint with water in a 1:3 water:paint ratio. With a small amount of paint on your paint brush, lightly paint the surface of the galvanized bucket. If there is too much paint rub the paint with a balled up newspaper to give the appearance of aged white rust.
Another time tested method is to distress the metal by denting or putting holes in the metal. Aesthetically placed dents give the product a one of a kind look that shows a rustic, rugged style. Nuts, bolts or even wood that are strategically placed wherever the dent is to be located. Place the bucket on its side (if that is where you would like the dent), and simply press down onto the bucket. To make holes in your bucket use a drill. We made this metal bucket light pictured below with a drill.
Aging galvanized products is not a hard process, but the treasures that the process creates are well worth the effort. Never has the procedure been so simple using just normal, everyday products. Enjoy!