I want to paint the kitchen furniture gloss white, but the wood pores remain visible. How do I do it?

I received this question from someone very knowledgeable about wood, but less so about painting and varnishing it, as he prefers the natural look given by tung oil. About the necessary conditions to obtain the best possible gloss I've written about furniture before, but not about the combination of open-pore wood paint and high gloss, when everything becomes a real challenge. That's why I found the subject interesting for professionals and enthusiasts and I'll elaborate on it below.

Why visible pores are a problem for gloss

In order for the pores not to be covered by the finish, to be visible and thus ensure the appearance of wood even if it is painted, the amount of material applied to the surface must be small. On the other hand, a very flat and well sanded surface is needed to achieve gloss, and a minimum of 2 coats of primer is needed to sand well. As you can see, the two requirements are pretty much head to head. When you consider that on top of these coats comes one coat of paint, it becomes clear that it's hard for the pores to remain uncoated.

The light comes from the reflection of the world on the lacquered surface. If this is not perfect the percentage of reflected rays will decrease and the gloss will not be as good. A surface on which pores are visible cannot reflect light 100%, so high gloss will not be achieved. Fortunately the requirement is to get a 70 gloss surface. This is also quite high, but if certain rules are followed, it can be achieved.

What are the conditions to achieve a glossy surface

The first is that the wood is well calibrated and polished so that the surface is free of bumps and imperfections. I have written several times about vHigh-gloss MDF coating, a material used a lot in glossy furniture. In this case the problem of calibrating the panels disappears, as they are ready calibrated in the factory. Sanding is only done in the milled areas and that only to remove the raised fibre. With wood the situation is different, and the calibration and sanding must be done perfectly to obtain a quality gloss.

The conditions in the space where the primer and paint are applied are very important. The room should be dust-free, there should be no draughts to bleed the still-wet film and the temperature should be as close as possible to the optimum 20°C.These conditions are found in a pressurised spray booth. If this is not available, a space as dust-free as possible must be found, away from mechanical processing areas. Those who achieve high gloss know that if dust particles appear, they can be removed by polishing. But in this case it is more difficult because the coating is thin and another sanding, no matter how fine, could ruin the surface.

The paint must be of good quality, spread very well and not make orange peel. To be applied with high-performance systems that do not include air in the film. Paint application by brush is excluded. No matter how good the varnish is, it will not sit well enough to provide the desired gloss.

What are the steps to achieve such a finish

In order to achieve a quality finish, the wood must be well calibrated before starting any mechanical processing necessary to obtain the furniture. Then, once all the furniture elements are ready or the furniture assembled (depending on requirements), everything is sand again with sandpaper 180, even 220 so that the surface is as smooth as possible.

The primer and paint used should both be white, of good quality and in my view solvent based. Solvent lifts the wood grain less and so sanding will be easier. The amount of primer applied will be the amount needed for one coat, but it will be applied in 2 batches. One coat means 2 passes of the gun over the surface to be painted, one perpendicular to the other. In this case one pass will be made, allowed to dry and then sand very well to remove raised fibre. After sanding, make the other pass perpendicular to the first one and sand again after drying. This time the sanding will be lighter, just to remove small imperfections. The primer should spread very well (no orange peel) and have a high resin content. Dusting should be done very well after each sanding so that the resulting dust does not remain in the pores.

Finally apply the white paint, well diluted so that it spreads without orange peel. A good spray gun will help to achieve a surface without bubbles or run-off. Until completely dry, the furniture should sit in a protected environment to avoid trapping dust particles in the film so polishing will not be necessary.

Getting the shine is not simple, even if it is just 70 gloss. There are no paints that can do wonders, only good materials, respected technologies and a space suitable for such a not exactly easy task.