Oak wood, prized for its robustness, carries the dilemma of tannin stains caused by tannic acid. These stains occur due to moisture and iron/metal contact. But how can tannin stains be removed? For example, with our OLI-NATURA Tannin Remover. This video shows you how.
Popular oak wood, in particular, contains a high proportion of tannic acid, known as tannins, which are found in both the bark and the wood of the oak. However, tannic acid is water-soluble and plays a significant role in the formation of unsightly water rings and black stains on wood surfaces.
WHEN DO BLACK STAINS OCCUR?
Black stains occur particularly when tannic acid comes into contact with iron or metal particles and water. This can happen, for example, if a metal can is placed on a damp oak wood surface or iron table legs are placed on freshly cleaned oak parquet. Even metal shavings can cause such discolouration. The resulting oxidation reactions lead to permanent, dark discolourations that cannot be simply removed by conventional cleaning methods. Here we provide practical solutions for their prevention and treatment.
MEASURES AGAINST TANNIN STAINS:
-
Prevention by Wetting (Water Popping):
To prevent the formation of tannin stains, it is advisable to wet oak wood before oiling. This traditional technique, known as water popping, helps to wash out some of the tannins. A dash of intensive or outdoor cleaner further reduces the reactivity of the tannins.
-
Treatment of existing stains: Not every oak wood table or floor has been pre-treated with the traditional wetting technique, which can lead to unwanted stains. In this case, our OLI-NATURA Tannin-Remover based on oxalic acid provides a remedy. The OLI-NATURA Tannin-Remover can simply be dripped onto the affected area. After a short exposure time, the area should be wiped with a damp cloth and re-oiled. Alternatively, the stain can be carefully sanded and then re-oiled to restore the appearance of the wood.
STEP-BY-STEP - Instructions for Tannin-Remover:
2) Dampen a cotton cloth with lukewarm water and wipe over the affected area. 
3) Let the surface dry thoroughly. It may happen that the area now appears lighter than the rest of the surface. 
4) It is therefore important that the area is subsequently treated with oil and wax to protect the cleaned surface again.
Which oil or wax is right for me?
If you want to buy wood oil, the selection initially seems huge and confusing. We help you make a decision and show which OLI-NATURA oils & waxes are best suited for you or rather for your project. Our experts will quickly and easily recommend a suitable wood oil, answer your product questions and give application tips. We are happy to help you with all your questions, by phone at 037208/84-488 or by e-mail at faq@oli-lacke.de.
