Cleaning and polishing brass can be quite a chore. This is especially true if you do boat restoration. Some of the brass I’ve encountered is older than I am. I’ve often wished for a good brass cleaner that could do the manual work for me. Well, true to my nature, I’ve experimented with a few ways to chemically clean the brass oxidation and have hit on a method that really works.
Most of the brass from old boats that I’ve worked on have a green to blackish patina on them. Personally, I prefer the gleaming shine of polished brass. As a result, I tackle these brass parts with vigor. And you do need vigor to manually clean these parts to a mirror finish. In this example, I’ve cleaned up a set of Norman pins from a 1966 Boston Whaler 13 by hand. I still had two more sets as well as three brass interior bow eyes
Cleaning Brass The Old Way
traditionally, what I have done is wet sanded the patina off of the old brass. I typically started with 320 and worked up to 400 Grit wet/dry sandpaper. I may go up several grades of sandpaper depending on what type of metal I’m working on. The finer the grit you end up with, the less time you’ll have to spend on the polishing wheel.
The biggest challenge with older pieces like this are the nick and scratches that most of them have. Years of hard use will take it’s toll, and brass is no exception to this. The deeper the nicks and scratches, the harder it is to get the oxidation out of them. So I would sand, and sand, and then sand some more. After about a half hour of sanding, I start thinking about what I could use as a magical brass cleaner to get the oxidation off without all the elbow grease.
The Homemade Brass Cleaner
Naturally, I started experimenting with various household ingredients to see what I could come up with. Most of these involved things you could find in the kitchen. To my surprise, a simple solution of vinegar and salt seemed to work the best. I placed the aluminum foil (folded so that the shiny side is up) in the vinegar and salt solution. I then place the brass pieces on top of the foil. Within minutes, you could see a fine stream of bubbles coming off of the brass.
The Ingredients for Homemade Brass Cleaner
How the Homemade Brass Cleaner Works
Whats really happening with this cleaner is that we are creating a sort of battery. When you place to dissimilar metals in a conductive solution, there is a flow of electrons from on to the other. In essence what we have here is that the aluminum is acting as a cathode and and the brass as an anode. As a result there is a fine layer of oxidation actually being formed on the brass. It appears that this process of creating new oxidation on the brass somehow loosens the old oxidation. This makes it easier to remove all of the oxidation with just a light scrubbing. I’m not 100% sure of the exact science behind it but I do know that it works!
Getting the Final Finish
After sanding to the point where I had all of the oxidation removed, I typically use a polishing or buffing wheel mounted on a grinder. This involves using a polishing compound. I keep the red and white polishing compounds around for various projects that involve polishing metals. For brass, I like to use the white compound. The white compound is less abrasive then the red. If I were polishing steel, I would start with the red and finish up with the white. In this case, the white polishing compound leaves a brilliant shine.
Preserving the finish
There are several methods of preserving the fresh new shine on the brass. You can use linseed oil, that dries to a hard finish and protects the brass. Another option is lacquer. Lacquer is commonly used as a finish on brass products. Polyurethane spray is yet another option that will protect the finish. Personally, I prefer to leave the finish as is. Once all of the major corrosion and oxidation has been removed, follow up cleaning and polishing should be a breeze with consumer brass polishing liquids such as brasso.
You can watch the YouTube Video of this article here: Secret Trick for Cleaning Brass and Copper – DIY Brass Cleaner