Preparing a wooden surface for painting.
Whether, whether we are dealing with a new raw material, or with the surface cleaned of old paint, three coats of paint must be applied to the wood: groundwater, base and decorative. We will achieve a smooth finish by removing any unevenness with sandpaper or a sander. Exceptionally uneven surfaces can be smoothed out with coarse-grained paper, but remember, to use a softer paper at the end.
After filling the gaps with putty or mortar, the knots should be soaked with shellac, preventing the resin from reacting with the paint. The primer closes the pores and provides a solid base for the next layer. Standard white paint is suitable for most types of wood, however, resin surfaces require a special paint. You can also use a universal primer, although the best results will be achieved by using products designed for specific materials.
Primer paints, due to its covering function, usually have a strong admixture of pigment, therefore always choose the shade recommended by the manufacturer for the chosen color of the top paint. Sometimes it is necessary to put two coats of primer paint.
1 Smooth the surface with sandpaper and impregnate the knots with shellac.
2 After a few days, apply a coat of primer and sand it.
3 Once dry, apply at least one coat of well-mixed undercoat.
If you want to use a clearcoat instead of a covering paint, you can use a waterproof putty (putty) available in many colors. Some kits are sold ready-made, others require combining the paste with a special hardener.
After drying, they have the natural color of the wood and can be tinted in any shade of your choice. In both cases, apply them with a putty knife, let it dry, then sand and apply a water or spirit stain. You need to be careful, in order not to apply unnecessary putty on the surface next to the cavity to be filled. Small gaps, often forming in window frames and joints, can be closed with putty by pushing it with your finger, then even with a damp cloth. Porous chaff plate requires the use of resin and oil putty.
Kit can also be used to cut out cavities. You need to remember to choose the right color.