Many metals tend to rust over time. At the same time, some rust very quickly, while others are more resistant to this process. If you decide to paint rusty metal, it must be carefully prepared for this, regardless of its composition.
Mechanical rust removal
The first step in painting a rusty metal is to clean it from rust. This process can take a lot of time, but without it, the quality of painting will be extremely low. To remove rust, you can use, for example, a wire brush. Such a tool can be used either manually or to find a special nozzle for a drill.
The surface cleaned with a brush will need to be carefully smoothed with a grinder. If you are faced with the task of cleaning a large metal surface, perhaps the best option would be to use a sandblasting machine. This device will help get rid of rust quite quickly, without spending any special effort. In addition, such a machine will help you deal with rust in hard-to-reach places where manual removal will not be possible.
Chemical rust removal
To remove rust, you can also use special chemicals that simply dissolve it. Such agents, first of all, include strong alkalis and acids. If you decide to use this method, be extremely careful when working with chemicals.
You can not remove rust, but turn it into a durable film using chemical converters. Such converters can be purchased in the form of an emulsion or suspension. However, such tools have their drawbacks, for example, they add their own shade to the paint with which the metal is coated, in addition, the metal layer due to the use of these tools becomes somewhat thicker.
Degreasing
The next step in preparing the metal is to clean it from dirt and remove grease from the surface. Without these procedures, painting will also be of poor quality. Wipe the metal surface using a strong detergent. Such products are often made on the basis of citrus oils, which are very effective in cleaning rusty surfaces. After such cleaning, rust spots may appear on the metal. You can get rid of them with an ordinary solvent, moistening a piece of material in it.
Primer
The cleaned surface must be carefully coated with an inhibitory primer containing iron oxide or zinc chromate. Apply this product following the instructions for its use. Try not to use sprayers; the primer may not fill the entire porous surface of the metal.
