Priming wood surfaces before painting or puttying is an important step that can really make a difference. By priming the wood, you can make sure that it is properly sealed and give paint or putty a smooth, even surface to adhere to.
In the absence of a primer, wood may absorb excessive paint, resulting in an uneven finish and possible problems later on. Additionally, this may make putty less likely to adhere, particularly when filling in flaws like knots or cracks.
This post will discuss the benefits of applying a wood primer, the various kinds that are available, and how to pick the best one for your job. To achieve a professional finish, it’s important to understand the role of a primer, whether you’re working with new wood or restoring an old surface.
- Stages of preparation
- Degreasing
- Antiseptic primer
- Putty
- Paints
- Varnishes
- Penetrating primer
- Acrylic water-based emulsions
- Oil paints
- Alkyd enamels
- Video on the topic
- Wood Putty
- Furniture Restoration. Wood Putty Secret #2
- How to Putty Wood
- VGT vs Tikkurila. Wood Putty. Acrylic and Alkyd. Purpose – to seal cracks on the door at once.
- How to remove old paint? How to putty, prime and paint wood?
Stages of preparation
How is a wooden surface—whether made of solid wood, plywood, or lining—ready for painting?
- The wood is cleaned of grease and resin. If there is a layer of old paint, it is removed to the base.
Nuance: The previous coating can be covered with paints of the same type as the old one. Alkyd enamels can be used on alkyd, acrylic water-dispersion paints on acrylic, and so forth. The primary requirement is the integrity of the previous layer; paint that starts to flake off needs to be completely removed.
- The surface is primed with an antiseptic primer. Antiseptic primers for wood before painting are used to prevent rotting and get rid of woodworms; in addition, such primers mostly contain fire retardant (increasing fire resistance) additives.
- All defects (screw indentations, cracks, knots, pockets, seams between plywood sheets) are putty. After wood puttying, the surface needs to be sanded; it is carried out strictly in the direction of the grain of the upper layer of wood. Sanding is often done by hand (with sandpaper on a grater or a block); however, the time and effort costs will be dramatically reduced when using a vibration or, which is much better, a belt sander.
- The surface is treated with a penetrating primer. There are several purposes of treatment: to increase the strength of the base, improve the adhesion of the paint layer and reduce its consumption. Priming with diluted paint is practiced; however, the price of a specialized primer of comparable quality is usually several times lower.
The primary operations will be examined in this order.
Degreasing
Usually, acetone, turpentine, or white spirit are utilized for this. A rag that has been liberally moistened with solvent is used to wipe the wood’s surface; resin pockets should be filled with a tiny quantity of solvent and blotted with a swab. This procedure needs to be done three to four times.
It’s common practice to use universal washes to remove old coatings. Following their application to the paint, polyethylene is placed over the wood surface and left for 20 to 30 minutes. Using a spatula, remove the softened coating.
Using the same steel spatula, heat the old paint with a gas burner or construction hair dryer before scraping it off. The residue is removed using the proper solvent; for example, acetone can be used to remove nitro paint residue, white spirit can remove alkyd residue, and so on.
Using a spatula, paint that has been heated to a soft consistency can be easily removed from the plywood panel’s surface.
Antiseptic primer
It is available for purchase as powders that have been diluted with water or as concentrated liquids. The antiseptic has very easy preparation and application instructions: just dissolve it in the water volume recommended by the manufacturer and use a wide brush or paint roller to apply it to the wood once. Primers can be applied directly to individual lining boards or small bars.
Acrylic penetrating primers with antiseptic additives are frequently available for purchase.
- Primer for wood for painting
Putty
What is used to putty wood? Everything is dependent on the final coating type.
Paints
Acrylic putties work best for puttying under paint on wood. Their higher elasticity helps prevent cracks during temperature and humidity fluctuations, setting them apart from universal ones. Using a steel spatula, the putty is applied in two stages, followed by grinding and intermediate drying.
Why precisely in two stages? because when acrylic mixtures dry, there is a slight but noticeable shrinkage.
Varnishes
It is preferable to use a homemade mixture of PVA glue and sawdust from wood sawing to putty beneath transparent varnishes. Putty made at home hardly ever shrinks; as the glue dries, it takes on the color of the wood instead of remaining white. It is also easy to sand and substantially stronger than acrylic.
Furthermore, there is no chance of seam cracks because the PVA and sawdust mixture’s coefficient of thermal expansion precisely matches the expansion coefficient of wood.
Pictured are ingredients for making homemade putty.
For a smooth and long-lasting finish when painting or puttying flaws, wood primer is a need. By sealing the wood, it gets the surface ready so that flaws and stains won’t show through the top coat. Your work will look professional and last longer if you use a primer to form a strong bond between the wood and the paint or putty.
Penetrating primer
The primer that should be used on wood before painting also depends on the final paint that will be applied. Let’s examine the most well-liked choices.
Acrylic water-based emulsions
Penetrating primers for wood or universal use, based on the same acrylic resins, are applied in this instance. One or two passes of primer application are made, with a mid-drying period. Avoiding excessive moisture is crucial for thin plywood and slats with small thicknesses as it can cause uneven swelling and deformation.
Oil paints
Drying oil is the best primer for wood to use when painting with oil paint. It is applied in two layers and left to dry in between for a full day.
For oil paints, natural drying oil makes the ideal primer.
It is recommended that you dry both the front and the back of the wood. By doing this, we can ensure that the wood will not deform when the humidity changes.
Hot impregnation with drying oil is frequently used to improve the protection of wood against moisture.
There are two approaches to this:
- The drying oil is preheated in a water bath and applied hot.
- After impregnation with cold drying oil, the wood surface is heated with a building hair dryer.
Alkyd enamels
Glymphalic primer GF-021, under universal PF-115 and floor PF-266, is used to prime wood. It is preferable to pre-dilute it with turpentine or white spirit. By doing so, we can guarantee that the primer will penetrate the base more deeply and adhere to it more successfully.
The glyphthalic varnish-based primer GF-021 is designed for use on metal and wooden surfaces.
Primer Type | Application |
Oil-based Primer | Ideal for sealing knots and preventing stains from bleeding through paint. Suitable for both painting and puttying defects. |
Shellac-based Primer | Excellent for blocking odors and covering heavy stains. Provides a smooth surface for painting and puttying. |
Water-based Primer | Low odor and easy to clean up. Best for priming bare wood and minor surface defects before painting. |
Priming wood before painting or puttying is an important step that can make a big difference in the finished product. It makes sure that the putty or paint sticks to the surface more firmly, resulting in a longer-lasting and more resilient finish.
Additionally, primers aid in sealing the wood, avoiding problems such as warping, discoloration, and uneven paint absorption. This keeps the wood safe from future damage while also improving the overall appearance.
A quick and easy way to guarantee the success of your painting or puttying project on wood and achieve a smooth, polished finish is to take the time to apply a high-quality primer.