The first step was to ascertain the color of the original paint. This was done by gently rubbing an area of the frame relatively undisturbed by corrosion with a fine piece of steel wool to get to the layer of paint below the surface dirt and damage.
Then a process of trial and error was used to match the paint color. The final color would be subtly influenced by the color of the primer. A white and red color primer were tried and the red gave me the best result. Using a primer is critical as it will prevent rust from occurring and provides a base for the top color coat of paint to adhere to. Rust from below the paint can begin if even a tiny amount is left after the frame is stripped to bare metal. Since I did not have a sandblaster at the time, there was no way to ensure the this was 100% certain. The red primer is what is called 'rusty metal primer' and arrests any small bit of missed rust that can act as a catalyst for the spread of new rust under the paint. The primer must be applied as soon as possible after stripping of the frame since oxidation of bare metal begins very shortly upon exposure to the air. If this is not possible, wrap each piece in newspaper and put into a sealed plastic bag.
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The frame is treated with a paint stripper to remove most of the old paint and dirt. Common degreaser at full strength will do the job. Since the frame was not too badly oxidized I was able to clean the frame down to the bare metal using a wire wheel attached to a drill. Areas such as interior corners were done with a hand wire brush. In a later restoration, the frame was badly oxidized and a sandblasting machine was used.
Now comes the primer and color coats. I used two coats of primer and five coats of acrylic green color. This gave a tough deep color. Note that all frame and bearing block pivot holes were first masked. It is far easier to go through this step than to try and remove the paint from these areas later without damaging the surrounding paint and polished interior of the pivot holes.