How do you to stop Steel from rusting?
Steel is one of the most commonly manufactured materials but it rusts easily when subject to air and moisture.
Steel is made mostly of iron. When iron is exposed to both oxygen and water it will rust so steel must be kept clean and dry. So how do you stop steel from rusting?
There are three options to help prevent steel from rust corrosion.
Steel is a porous metal so it is important to dry it quickly and thoroughly. Steel items need to be stored in low humidity conditions.
High humidity means that moisture from the air will become trapped in the pores of the metal and will cause rusting.
Dirt and dust build up holds moisture and allows corrosion to occur even on a dry day.
Apply a Protective Coating
You can apply a coating or paint to protect your metal from rusting and is likely the most economical option in the long run.
To stop Steel from rusting the best solution is to protect it with a coating
Mild steel (aka carbon steel) eventually rusts unless it is treated with some sort of protective coating to prevent corrosion. When other elements are introduced like molybdenum, titanium and chromium which improves corrosion resistance it does not make the steel rust proof.
Which Coating for Mild Steel – Everbrite or Protectaclear?
Everbrite™ coating is suitable for most mild steel projects. It is thicker and works well with porous metals like naturally rusted metal, corten or other steels. For certain rusted metal projects ProtectaClear® is needed for metal countertops, sinks, or any surface that gets a lot of high use or abuse which will require the hardness of ProtectaClear®. ProtectaClear® is thinner, so additional coats will likely be needed.
All of our coatings are heat resistant up to 260 – 285 degrees centigrade. The coatings will gas off at about 350 degrees centigrade.
How much coating do I need to seal mild steels?
Mild Steels are more porous than smooth metals; and can take up to 50% more coating for the first coat. The thicker the rust, the more coating it will take to seal it.
Generally it will take 3+ thick coats to seal exterior rusted metals; or 2 thick coats for indoor locations; as long as the substrate is sanded to a smooth finish with all loose rust has been knocked off.
For exterior multiply the surface area to be coated by 3.4
For interior multiply the surface area to be coated by 2.4
e.g. 2 square metres surface area in an outside location will require coating to cover 6.8 square metres. (3.4 x 2 sq m.)
Which finish? Natural Gloss or Satin?
The clear formula of Everbrite™ or ProtectaClear® can be glossy on dark coloured metals. Once it is coated, the metal will look like it does when it is wet. The Satin formula can be put on to reduce the shine if the original is too glossy. The Satin finish has a sheen but not a shine. If Natural Gloss has been used but a lower sheen finish is desired, we recommend the Satin finish of Everbrite™ for the final coat(s).
- Mild Steel is porous so care must be taken to ensure that the metal is completely clean and dry. A solvent like methylated spirits is used to help remove contaminants like grease or oils. The solvent will also help draw out moisture because coating and sealing moisture in the pores of metal can cause failure of any coating.
- The metal MUST be completely dry and smooth before applying the coating.
- If an acid based compound has been used to assist with the rusting process then the metal will need to be neutralised and thoroughly rinsed off with clean water and then dried well (bone dry) before solvent wiping.
- As raw steel is so porous 3 to 4+ coats are recommended with the first coat requiring extra coating than normal.
- Everbrite™ and ProtectaClear® will seal the metal and it will look great for years and can be maintained indefinitely.
Mild Steel sculpture coated with Everbrite
Coated with Everbrite – Is it a Motor or is it a BBQ?
Knowing your Steels
Providing steel with a thin layer of material that doesn’t rust is an effective way to protect the steel from corrosion. The most common methods for protecting metals from corrosion.
Zinc (Galvanized Steel)
Coating steel with zinc is also known as galvanizing steel which does an excellent job of preventing rust. But if the surface gets scratched or worn away, then the now exposed steel will begin to corrode.
Chromium (Stainless Steel)
Steel coated with chromium oxide is known as stainless steel, and is the most widely manufactured corrosion resistant steels. Chromium acts as a barrier of oxygen from reaching the iron in the steel and gives a clean and polished finish that makes it practical for a wide range of applications.
Aluminium (Aluminium Steel)
Steel that is coated in with aluminium-silicon alloy has more resistance to corrosion than steel and is stable in extremely high temperatures. while not rusting. Used for car mufflers, ovens, water heaters, and fireplaces.