Ask Dave about Wood Finishing
QUESTION: How can I remove water stains and other stains from wood before staining?
ANSWER: Water stains rust stains and tannin acid bleed can be removed with Oxalic Acid. Oxalic acid is the main ingredient in many products such as DECKSWOOD. Oxalic Acid can also be purchased in powder form to mix a more highly concentrated formula. Simply wash the stain with Oxalic Acid mix or product and rinse with water to remove the stain.
QUESTION: Why does a lacquer fail so often on cabinets around sinks?
ANSWER: Because of the fast drying nature of lacquer it does not penetrate into the wood deep enough to get a bite and when water is present the wood swells and the lacquer pops. My recommendation is to isolate the doors and drawers that are beneath the sink or areas that will get wet. After staining apply 2 coats of water base polyurethane to seal the wood. Sand the water base polyurethane and apply the finish lacquer just like the others.
QUESTION: Many of the woods I use like maple and pine stain very unevenly, what can I do?
ANSWER: Wood such as pine is best stained after first using a stain controller. A stain controller is simply an oil that is spread upon the wood and the areas that are most porous absorbs more of the oil. The oil now has filled the porous areas of the wood and will not allow the stain to penetrate as deeply. Then when you apply the stain you will achieve more of an even appearance overall.
Another difficult wood is Maple; it stains unevenly because of the change in direction of grain. When selecting a color for maple, pick a stain that is a much lighter than the desired end result. Stain it with a gelled stain such as WOODKOTE, orMINI WAX, etc…. Seal the lighter version and then apply the second coat of the gelled stain like a glaze to even it out. This is called "toning". Another way to tone in a lacquer system is to thin the gelled stain using lacquer thinner to a very thin consistency. Spray the gelled stain on evenly. CAUTION…spray very light coats and build. The toning process does not allow you to back up once you have gone to dark. If this occurs, you will have to strip the piece and start again. In the "toning process many of the inside corners of raised moldings may appear lighter after the wood has been sprayed. Apply another coat of sealer and then wipe on another coat of the jel'd stain to darken the inside corners. Once the even staining process is achieved, the entire project is again sealed and then finished.
QUESTION: What can I do about wood putties that do not stain and match the wood?
ANSWER: Select a wood putty and I prefer the fast drying acetone base putties like, "fix it" that best match the wood, (before the wood is stained). After the staining process and the wood has been sealed look for those holes that don't match and using a nail punch set the putty a little deeper and use a touch up stick that can be purchased from MOHAWK finishes. Apply the touch up stick to the perfect color match, there are many colors to choose from. Remove the excess with steal wool and apply the finish coats of lacquer for a perfect wood filling.
QUESTION: I am confused about GLAZES, I hear the word used in so many different ways, what is a GLAZE?
ANSWER: A GLAZE is a semi transparent to translucent coating which allows the surface beneath it to shine through it, or show through it. It is used to "highlight", "tone" or "texture" a surface. Glazes can be made out of oil base glazing liquid, water base glazing liquid, thinned down paints, stains, and pigments in paint thinner, pigments in water. There are many different kinds, some will dry hard and will be a finish coat, and some must be coated to stay fixed.
QUESTION: What exactly is "Water Spotting", the technique for wood finishing?
ANSWER: Water spotting is simply a chemical reaction between 2 products resulting in a texture on a wood finish. This transparent texture resembles the look of an old antique faded multi colored piece of wood. There are 3 ways to achieve this look:
First way- Using benzene or naphtha. This comes packaged as VM&P Naptha When naptha is sprinkled on an oil base stain or even UTC's mixed in paint thinner. While it is still wet, the little droplets will separate the pigments and leave a beautiful texture and finish. From there while it is still wet it can be dabbed with a cheese cloth to break it up even further thus creating a very old spotty transparent stain.
Second way Apply a coat of UTC stain (UTC colorant mixed with paint thinner) evenly over a sealed surface. While the stain is still wet spatter more of the stain onto the surface. The color will separate and then blend. Do this as many times as is necessary to achieve your desired results.
Third way With a water base system-using PTC's like the PROLINE pigments mixed in water. Make the stains by sprinkling it with denatured alcohol. Denatured alcohol has the same effect. All of this has to be done while the products wet. This process is best done on horizontal surfaces; the results are dramatically different. So when you are doing cabinets for example, you want to make sure that your cabinet doors be done on a table surface and the cabinet framing which is already upright, match. Often times we will do the water spotting technique after the doors are hung and before the actual finish coat is applied.
QUESTION: What is the best way to use WAX on a finish?
ANSWER: Waxes are very important and have many uses. We used to use the old pigmented wax type shoe polishes that came in many colors and in effect did the same thing to furniture that it did to shoes. Furniture can be touched up with pigment waxes because the pigment colors in the imperfections, the dings, the dents, and the scratches and at the same time giving it a new luster. Waxes can be used as a finish in it self. Color waxes can be used right over raw wood giving it a luster and a stain. I prefer to first apply either a lacquer sanding sealer or an oil product such as WATCO or ZAR tounge oil finish to soak into the wood and seal it. The sealed wood gives the wax a base to develop a more brilliant luster. We also use waxes as a way to finish off a lacquer topcoat. The wax smoothes out areas with over spray and the wax accumulation in the corners of moldings creates an even finer looking finish. Apply it with #0000 steal wool, allow to dry and give it a nice buffing. There are many products on the market such as MINIWAX and BRIWAX, and they have an excellent selection of colors.
QUESTION: How do I remove wax from a finished piece so that I can lacquer or apply more lacquer?
ANSWER: Most waxes can be removed by cleaning the surface with toluene. Toluene will clean the wax off, then a light sanding is required. To ensure that you don't get "fish eyeing" from the previous wax use a little bit of "smoothie" or "fish eye flow out" in your lacquer for your next coat.
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