Galvanized steel is the go-to solution for blocking the process of rusting for iron and steel. When metal like iron comes in contact with air and moisture, the topmost layers start to corrode due to the metal’s chemical reaction, atmosphere, and humidity. A layer of any other metal or mixture of metals is applied to prevent the surface. Metals that are known not to react in air and moisture are used for the said process. This process of covering the steel or iron with another metal is called galvanization if the choice of metal is zinc. It is imperative to know how to paint galvanized steel before you go ahead to paint one.
In recent times, a lot of work has been done to ensure that the process becomes more comfortable to operate. Because of this sacrificial nature, the zinc’s coat is affected by air and moisture before it gets to the steel or iron.
Applying paint on the galvanized surface offers an extra protective layer. This layer of paint provides another layer on the zinc layer that needs to be invaded before the air and moisture get to the base metal. But painting a galvanized surface comes with its challenges. Hence, there are a lot of guidelines on how to paint galvanized steel. In the modern age, almost every steel or iron product under usage goes through galvanization and painting. Few benefits of galvanizing the product:
- It increases the durability of the product. Because of the delay in corrosion or rust, the effect lasts long and can be used for a more extended period. A galvanized surface can survive an unfavourable weather situation with rough water and air for almost 20 years. If the weather is favourable with regular moisture and air activity, it can go up to 50 years.
- The cost of the product under usage reduces by notches because ready to use galvanized steels are available. It is more cost-effective to buy a galvanized iron or steel piece than buying an ordinary one because it saves the cost of galvanizing it separately. The galvanized surface has already gone through the required inspection and then ended up in the market. Hence, the reduced price.
- The sacrificial nature of zinc delays rusting the primary surface by almost a few decades.
- There are different types of galvanization process that fits various kinds of requirements of the base metal. So, there is always something to suffice the need of yours.
- The process of galvanization is neither complicated nor long or tedious or costly to go through with. So, every household can easily reap the benefits of galvanized iron.
- Galvanized iron and steel requires significantly less maintenance. Hence, it is quite user-friendly.
Challenges faced in painting a galvanized iron
Galvanized iron undoubtedly has many benefits attached to it, but one of the main challenges that are faced during us painting them. Because of the zinc layer coated, the paint might not adhere to the surface, and it is expected to. Oil-based paints are preferred in this case. But it may start to shed after a few days or months.
Same is the problem with the alkyd-based paints. In addition to these, the colour’s chemical composition may start to react with the zinc in the coating. These reactions also interfere with the binding capacity of the paint. So, the main problem is to overcome the peeling of the colour from the surface.
How to paint galvanized steel?
Though different kinds of galvanization require different types and procedures of how to paint galvanized steel, there are few basic rules and lines of the process that are followed in all of them. The primary few requirements to have a good layer of paint on the iron surface are ammonia, the sandpaper of 240 grit, tack cloths for cleaning, metal primer and metal paint. So, we will give an overview of how to paint galvanized steel:
- The base metal sheet is cleaned at first with hot and soapy water to be freed from any dirt or dust. This process ensures that the paint layer to be coated on the base metal does not go through any unnecessary chemical reaction that might interfere with the durability of the zinc metal coating.
- After cleaning it up, the metal is then dipped into a weak solution of ammonia. This process helps clean the piece of metal even more thoroughly and prepares it for any further use.
- Sandpaper is used to give a smooth finish to the metal surface and make sure it does not have any inconsistencies.
- The sheet metal is completely dried off and wiped off using a piece of tack clothes to prepare it for further process.
- The primer is applied to the surface as evenly as possible. Using the primer evenly plays an essential role in ensuring that the paint adheres to the body for a more extended time.
- After applying the primer, the paint is applied to the surface. The primer and the paint are preferred to be of the same company. It is also mandatory to follow the directions printed in order to get the desired result.
1. What kind of paint do you use on galvanized steel?
Ans: High-performance acrylic paintings are perfect if the galvanized steel has been prepared well. It generally accepts any alkyd, acrylic or a two-component outcome as a finish coat.
2. Can you paint over galvanized steel?
Ans: High quality and best products are required when it comes to applying paints on galvanized steel. Because of the zinc coating, the paint does not adhere to the surface well in the long term.
3. Do you need to prime galvanized metal before painting?
Ans: Yes, priming is very important when it comes to painting the galvanized metal. There are different types of priming that can be done in order to be able to apply paint on the surface and expect it to adhere for long term.
4. Will Rust-oleum paint stick to galvanized metal?
Ans: Yes, rust-oleum is one of the better choices when it comes to applying paint to galvanized surfaces. It sticks well to aluminium galvanized surfaces, and it is also an easy to clean process.
5. What is the best primer for galvanized metal?
Ans: Rust-oleum is by far the most suggested and preferred primer for all sorts of galvanized surfaces. It sticks well to the long-term body, and paint can be well applied on the surface after spraying it with Rust-oleum.
6. Can I use chalk paint on galvanized metal?
Ans: Chalk paint is not the go-to solution when it comes to applying colours on galvanized metal. The best type of paint that sticks and applies well to galvanized surfaces is the acrylic coating.
7. How long does it take for galvanized steel to rust?
Ans: If the situation is harsh, the galvanized steel can survive for 35 to 40 years. But if the problem is favourable, it can go on to stay for 75 years or more.
8. Will vinegar rust galvanized metal?
Ans: The acid present in vinegar may start to rust. If you spray white vinegar and leave it to dry, it will begin to rust as soon as the vinegar dries.
It is tough to find an industry that does not use galvanized metal in this day and age. Few of the most common users of the same are Construction Company, an automobile company, wind and solar industries, telecommunication industries etc. These different industries demand different kinds of painted galvanized surfaces.
Few may require the electro-galvanized, whereas the rest may require hot dipping. There are different kinds of certifications that are provided for perfectly painted galvanized metals. These certifications need specific standards to be maintained and also offer guidelines on how to paint galvanized steels.
These standards are set, keeping in mind the different requirements each industry may have. It is mandatory and safe to go through the certifications to ensure that the product quality is maintained well.
Although the painted galvanized process might not be the most sustainable and eco-friendly process to follow in order to protect metals from rusting or using them, newer methods of how to paint galvanized steels are getting discovered every day to make sure that the boundary of usage can be increased. These discoveries are also leading to more environmentally conscious industries to take up the product for their use.
Read More:- Top High- Efficiency HE Detergents