I have unfinished pine steps yet. What materials should I use to stain them oak and keep the grain visible?

I received such a question as a comment on one of the articles. As it required a more elaborate answer, I thought it might be of use to others who are faced with wood staining problems and don't know what to choose from the countless products they can find in the shops, both physical and online. The presentation made reference to the fact that the wood - solid fir - had been left outside to dry for years, was raw, untreated and unstained. Advice was sought on both staining and protecting the steps to be installed on a low-traffic interior staircase.

How to stain wood to keep the grain visible

The classic method of protecting wood so that the grain remains visible is with dye-based stains and clear lacquers. Dye-based stains are staining solutions made from thinners or water and soluble dyes. When applied directly to the wood, they are absorbed and bring out the natural design. In contrast to these solutions, there are pigment stains. These do not dissolve in water or thinner, they remain in suspension, and when applied to the wood they remain on the surface, giving a more uniform but less spectacular color, with the grain less visible. Semi-transparent pigment staining is mainly used outdoors (lazuri) because the pigments not only make the finish uniform, but also make it resistant to UV radiation. They are also used when the wood absorbs differently and stains or when the object, in this case the staircase, is made of different wooden elements and an ordinary stain would unpleasantly highlight the differences between them.

Stain stains can be water-based or solvent-based. Water-based stain varnishes absorb better into the wood and highlight the grain better. The disadvantage is that by absorbing water, the wood grain lifts and more vigorous sanding will be needed afterwards to achieve a smooth to the touch surface. Solvent-based polishes absorb less into the wood and give a duller appearance. The grain, however, will lift much less. Regardless of the type of stain, if over-applied and followed by wiping with a rag, the natural wood grain will be marred.

In this case, an oak-colored bath will be used. The treads are not fitted, so a solvent-based stain can be used, avoiding raising the fibers without bringing the lingering smell of thinner into the house. You can find such wood polishes in hardware stores or stores that carry wood finishing supplies. There are several types of oak balsam, so it's a good idea to check the color before using it. There is dark oak, light oak, medium oak, golden oak, antique oak, etc. Check the label and buy the one that has only dye and solvents. If you want the grain of the wood to stand out, don't buy baths that have pigments or significant resin additions.

After the varnish has been applied and dried, the first coat of varnish is applied, without sanding, even if the wood grain has risen and feels unpleasant. Sanding at this stage can spoil the uniformity of color. Sand after the first coat of varnish has dried. As it is a stair, we recommend the use of a solvent- or water-based floor varnish. It can be applied with a trowel. If you use solvent-based varnish, choose a solvent-resistant sponge.

Coloring can also be done with colored varnish

For those who want an easier way to get away without many coats and materials, there is the option of using an oak colored floor lacquer. Be careful, lacquer not paint, so that the wood grain remains visible. In general, commercially available colored varnishes have hardnesses suitable for furniture. If you want a harder varnish, you can make your own. The varnish must be compatible with the varnish in question (water with water and solvent with solvent). With solvent-based varnishes, check compatibility beforehand. It is possible that some dyes are not soluble in all the solvents in the varnish thinner and the color may change.

To color the varnish, add up to 10% bath. Even if the varnish is very diluted, it is not good to add more because it will dilute the varnish and the application will be more difficult (drips will appear). It is better to make the color lighter than desired, and the final color should result from the successive coats applied.

Application should be done carefully and evenly to avoid color streaks. The color will also darken with each coat applied. To avoid this effect, 1-2 colored coats can be applied until the desired color is reached, then continue with clear lacquer.

Sanding, very important to achieve even coloring and a pleasant surface to the touch

The success of solid wood staining depends on proper sanding. Proper sanding before applying the wood stain will make the wood absorb evenly, and the coloring will be uniform, without spots. If the wood is very rough, sand it successively with 2 different grits, for example first with a 120 grit paper, then 150 or first 150, then 180. After sanding, the wood is thoroughly sanded before applying the staining solution.

Equally important sanding between coats. It ensures not only a smooth surface but also good adhesion between coats. Sand after the first coat of varnish is completely dry. When staining the wood, the grain of the wood is slightly raised, and after varnish application, this raised grain becomes very hard and scratchy. To remove it and obtain a surface that is pleasant to the touch, sand the surface with 280 or 320-grit sandpaper or a fine sanding sponge. Do not sand after sanding as this will spoil the color uniformity.

Even though the color will be identical to oak, the final look of the stained fir will not be oak

I must draw attention to something I have come across many times. Those who use oak, walnut, or mahogany to color resinous wood (spruce, pine, fir, larch), the wood is expected to look like spruce, pine oak, nuc or mahon. It won't look the same because the natural grain pattern is different, and resinous wood has no pores. The lack of pores makes the look very different.

So, even if the stain used for the stair treads is oak, the stairs will not look like oak at the end, but like yellow-brown stained fir.

Wood acclimatisation indoors

And one more thing to be aware of when using wooden floors or steps that have been outside for a long time or stored in rooms with different humidity than indoors. Before finishing and installation, the wooden elements should be kept indoors for a few days to allow their moisture to reach in balance with indoor humidity. This avoids stresses in the wood after finishing, which can cause the wood to move and the varnish to crack.

I hope you find the information useful. If you have any clarifications or questions, leave them below in the dedicated space. I will certainly reply.