Depending on the condition of a plane, it will either be cleaned, or restored. Generally planes to be restored will have a good amount of rust, or a finish that needs to be replaced. Planes in reasonable condition, I tend to clean until I have time to perform a deep cleaning, which normally includes polishing the brass and nickel parts of the plane. But how to clean and protect the finishes on a plane (or any tool for that matter)? One way is by using Camellia oleifera, or Camellia oil.
Camellia oil, also known as tea oil, is commonly used in Japan to inhibit rust on woodworking tools. Toshio Odate, describes Camellia oil as “not too heavy, and gives a beautiful shine to blades”. It is traditionally applied using an aburatsubo or oil pot which is made out of a section of bamboo and filled with a roll of cloth. It is odourless, and non-staining. Below are some before and after photographs from applying Camellia oil to a Union block plane.
Note that the oil has the effect of suppressing the light surface, or “flash” rust, and providing a gentle sheen to the japanning. I apply the oil to the plane, use a brush to work it in, and then let it sit for 1-2 hours. After this I just wipe off the excess, and hand-buff the surface.
One of the most common brands available in North America is Kurobara Camellia Oil. Oil is also made from other related species, Camellia japonica (often used in skin-care products), and Camellia sinensis (tea).