Preparing unfinished furniture for stain.

As with most things, preparation is key, and preparing a wooden surface for a stain or lacquer is no exception.

This is an area where I cannot emphasize, and stress the importance of going through a procedure in a methodical way, in order to obtain a professional finish. It would be impossible to achieve a quality finish without the necessary preparation.If the
desired finish is to be painted, be it oil based, or latex, then there are a few corners that you may be able to cut, than if you were going to use a clear finish because paint will allow you to cover certain flaws in the surface, whereby a clear finish will merely highlight the imperfection.

There are generally three things to adhere to before commencing applying a finish, and a thorough job needs to be done. If a painted surface is required, it needn’t have to be done so well.

1.    Sand the wooden surfaces smooth.
2.    Remove any traces of glue that may have seeped from any joint.
3.    Make good any imperfections with wood putty and blend in.

For myself, being in the profession for most of my life, sanding wood to erase any blemishes or defects in the surface is very rewarding, and I find it extremely relaxing. For someone not in the trade, I understand that sanding a wooden surface through the various grades of paper can be a very laborious job, but unfortunately, a very necessary process to endure.

Make no mistake about it, it’s hard work, but it may make it easier for you if you understand why it has to be done.

Before the introduction of machine tools during the mid nineteenth century, very little, if any sanding was required, once the boards were shaped and joined. Sand paper, or glass paper as it is sometimes referred to wasn’t around, and any smoothing of wood was done by hand tools that left the surface perfectly smooth.

It is the machine tools that we have come to love, and that help woodworking so much easier, that cause you to have to work that much harder in sanding a surface before applying the stain and finish. It doesn’t matter how sharp your machine tool is, it will leave marks and blemishes in the surface. These will easily be visible once you apply a clear finish. Unfortunately, a lot of time and effort has to go into sanding and this is the price you pay for using machinery.

The purpose of any sanding project is to relieve the surface of any flaws, and remove any scratches that will be noticeable later. Before you commence, you will note that sand paper comes in various grades of coarseness, and this is clearly marked on the back of the paper. Depending on the severity of the surface to be sanded, will dictate, which grade you’ll require.

Generally speaking, the roughest grade for dry sanding paper is 40 grit, and will go up in increments to finer 500 grit. This is about as fine as you’ll ever need for dry sanding. The reason I mentioned dry sanding is because you can go up to 6000 grit but this will be used in conjunction with water. These higher grades are generally used in the paint industry, and are not relevant for sanding woo. They are far to fine to make any difference in the surface.

More than likely for an average type machined surface, you’ll begin with an 80-100 grade of paper. You should never sand with the paper placed in your hands, as this makes it virtually impossible to sand a flat surface. You will need to wrap the paper around either a sanding block that can be purchased from your local hardware store, or you can use a piece of off cut timber that you no longer require. To make it easier, you may prefer to purchase the sanding block as these are purposely made to accept the sand paper. They are often made of dense rubber, allowing a certain amount of flex, as you sand.

When sanding, always travel in the direction of the grain, never across. This will only compound the amount of scratches you need to eliminate, thus defeating the purpose. Replace the paper with 150, and repeat the sanding. By now you should be able to see a significant improvement in the surface. Most people would be happy with this finish, however I personally would continue through to 220 that will seal the deal.

Whatever grade you begin with, or finish, you need to progressively sand out all the scratches going only in the direction of the grain. This will be a learning curve and only time and experience will help you decide on the grade of paper necessary for each individual project.

Happy Sanding