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The work of a wood finisher is a huge task: preparing the proper finish, color matching, consistency and, ultimately, trying to make the customer happy. One of the major challenges is trying to break the process down into steps to make it easier to follow. This article aims to provide information on where to look for more detailed information on these subjects and other finishing subjects that everyone needs to know.

CONSISTENTLY CONSISTENT

Producing a consistent finish on furniture begins before any finish material ever touches the furniture. The substrate must be prepared properly every time to achieve the desired results. Problems with substrate preparation are often difficult to touch up after the fact, and many times require stripping all the finish off and starting over.

Paying for the initial finish — plus the cost of labor and materials to strip and refinish — can quickly erode the profits on a job. Defect prevention is necessary to compete in today’s highly competitive market.
For example, glue spots create quite a headache in the finish department if not caught before the finishing begins. Many times the glue spot will blend into the wood and is easily missed if not inspected closely; however, once finish is applied, it’s easy to see.

The sandpaper used will also affect the color, look and possibly the adhesion of the finish to the wood. Each person sanding the wood should know which type and grit of sandpaper to use where and why.

Besides the sandpaper, the sanding equipment can cause problems by leaving swirls in the wood; or if a contaminate gets under the paper, it can leave scratches. Both of these will show up as significant problems once the finish is applied.

Prior to finishing, problems like watermarks, poor fit of parts and other discolorations should be addressed. You’ll need bright lighting to see the problems, so make sure there is plenty of lighting before finishing. (For more information on the surface preparation, see the article, “Finish preparation steps,”1 Finishing, January 2006.)

TEST PANELS: THE BEST TOOL IN ENSURING CONSISTENCY

Once you are ready to start using the finish materials, the first thing to consider is the lighting. It’s difficult to match color, strength and depth with out proper lighting.

As you go, you will need something to compare the parts being finished with to know if they are correct at each step. Correcting problems when they happen is much easier than after the fact, and it will allow you to prevent repeating it. Create stepped color standard panels when a finished panel is produced for the customer to see and approve. The color standard panels should be large enough to easily see each finish step to compare to, and enough panels should be created for each person applying finish to have their own panel. The parts need to be compared to the color standard panels at each step every time.

Wood can vary in color and porosity. It is important to optimize your finish process to balance out these variations in the substrate. Wiping stains, filling stains, glazes, spray stains, NGR stains, sap stains and toners are commonly used together to obtain uniformity of color while still seeing the natural beauty of the wood through the finish. (For more information on step panels, see the article, “Optimizing your process to achieve the perfect look,”2 Finishing, September 2006.)

Close attention to detail is important not only for appearance concerns, but also to prevent durability problems. Too much glaze or filling stain left on the parts must be looked for carefully as it is difficult to see. An excess of these products can interfere with adhesion of the finish coats. Even the most durable coating will chip and peel if it doesn’t adhere. (For more information on coating durability, see the article, “Color matching tips,”3 Finishing, August 2006.)

Now that you’re getting a consistent color, here’s how you make sure you get a consistent gloss, or sheen, on the furniture to enhance the appearance. The customer will notice if the sheen varies from part to part. Just because you are using a 50 sheen coating, does not mean your furniture has a 50 sheen gloss level.

Besides the coatings gloss rating, the thickness of coats, sanding, type of finish and wood can all affect the final gloss level. It is also important to acknowledge that your finish process is different from the specifically designed and consistent laboratory process used to check the gloss level before the finish is sold to you; therefore, make sure to check the gloss level of the furniture coming off the line to verify its consistency.

A simple comparison to a standard color panel’s final area can allow for a visual check; however, it is vital to take care in handling and storing the standard panel as wear and contaminates can change the appearance. If you have the means, a digital gloss meter is ideal for evaluating the gloss level. This takes the subjectivity of the human eye out and allows for a far more accurate gloss reading. (For more information on using gloss, see the article, “Keeping the gloss consistent,”4 Finishing, September 2007.)

Many finishers are separating themselves with increasingly sophisticated finish looks. Value-added looks can be very profitable; and proper processes and testing can ensure that the finish is as durable as it is fashionable.

There are so many types of substrates and finish materials it is impractical to test every possible combination, especially if different coating manufacturers’ products are used together. Consequently, it is of the utmost importance to test new finishes — especially complex finishes — for durability. If you don’t, it can mean producing an attractive finish that won’t stay attractive for long. Using fillers, crackle, toners and glazes can cause durability problems that need to be found out before finishing furniture. The stepped color panels being used for developing a new look are great for testing the durability of the new finish process.