How to remove rust from metal fences

August 2020 – Do you have a metal door or fence in your garden or balcony that has already started to rust and now it is time to renovate it? Autumn is the perfect time for that kind of job. Temperatures will be just right for repair and painting, and your fence will be restored and protected for winter.

First, let’s look what is rust? When iron, iron alloy, or steel come in contact with water and oxygen, a reaction called oxidation occurs. The material corrodes, that means it is coated with hydrogenated iron oxides of reddish-brown colour and scaly form better known as rust. All metals are susceptible to corrosion in one form or another, but the word rust is used only when referring to iron, iron alloy and steel.

To achieve the best possible final appearance of the fence, which will also last for many years to come, it is crucial to prepare the surface before repainting. This is sometimes time-consuming, but it is really essential that we remove as much rust and old paint that is peeling off the surface.


The most effective way to remove rust and old paint from metal products is with the help of wire brushes and fan grinders mounted in a hand drill / screwdriver. It is much more efficient, faster and less strenuous than manual metalworking. When working, make sure that you reach all hard-to-reach places with the brush. Namely, if they are not properly prepared for painting, rust will reappear in a very short time. When working with power tools where the turns are higher, also take care for your safety. We recommend the use of appropriate protective gloves and goggles.

However,not everybody have such a tool at their disposal so we must therefore look for an alternative. Wire brush and sandpaper are the most common ways to remove rust and old paint from metal doors and fences. If you choose to use them path, do it really thoroughly. Above all, be careful to treat all curved and hard-to-reach areas, as rust reappears the fastest in these places due to the water, which tends to stay there for a long time.

Next step is one of the most important ones if we want to prevent re-rusting. Once you are sure that you have mechanically treated all the problematic areas of rust and old paint, first apply Ferrosan to the surface you intend to paint. Ferrosan is a multi-purpose agent for removing rust residues from rusty iron surfaces. Due to its corrosion inhibitor, it also offers short-term protection against further rusting until coatings are applied. Ferrosan reacts with iron oxides on the surface and converts rust into a protective layer. The surface treated with Ferrosan is therefore compact and suitably prepared for the application of an anti-corrosion primer. Ferrosan does not offer long-term surface protection, so surfaces treated with Ferrosan must be adequately protected in a short time.


First, you must mechanically clean all the rust that does not adhere firmly to the rusted iron surface that we want to clean with Ferrosan. Only compact and well-adhered rust can remain on the surface. Cleaning gasoline or thinners can be used for degreasing. The prepared surface can then be treated with Ferrosan by coating, spraying or dipping. Wait for approx. 1-2 hours to allow the surface to dry completely. During this time, a white or gray compact layer forms on the surface. If rust residues are still visible, you need to re-treat the surface with Ferrosan once again. The treated surface, which is completely dry, undusted and compact, is ready for further processing – coating with paints, varnishes, galvanizing, nickel plating, chrome plating, etc.

Important: provided that due to the excessive application of Ferrosan or. minor rust on the surface Ferrosan coated surface does not dry out (chemical reaction of conversion of rust to a protective layer does not take place), you must remove excess Ferrosan from the surface before further processing (hint: such surfaces usually have a greasy appearance). Excessive amounts of applied Ferrosan can be removed with water. The dried surface is thus perfectly prepared for further processing.


WARNINGS: Ferrosan is classified as a hazardous chemical according to the classification criteria (according to CLP-EU GHS Regulation 1272/2008). Read the label carefully before use and follow the instructions for use. More detailed information on hazardous properties and safe handling of the product is provided in the product safety data sheet. The product is intended for consumer use and for professional use.