Various Finishing Techniques

Etsy

One of my heroes of woodworking is David Marks. He used to have a show on PBS Called “Woodworks” on which he made numerous unique wood items step by step for all of us novice woodworkers to emulate. I used to watch that show, and wish I could finish all of my woodworking creations to look even half as good as his. Recently I found his finishing formula that he has perfected over years of trial and error on his website, Djmarks.com. I am re-posting it below:

David Marks Sanding Formula

A high quality finish starts with good surface preparation. This means thoroughly sanding the surface with 220 grit sandpaper or higher. I usually sand to 320 grit to bring out the clarity of the grain. Because of the time limitations of the show, we generally don’t demonstrate much sanding. After removing the dust (I use compressed air, if you don’t have compressed air, a vacuum cleaner and tack rags work well), I apply the first coat of sealer (Seal-A-Cell) liberally to the surface allowing it to soak in for a few minutes and then use some soft rags and buff off all of the excess. This is important otherwise you will have resins that get sticky and leave an uneven surface. I let this coat dry overnight preferably at 70 degrees or warmer. A cold and damp environment can cause a finish to lack clarity and delay drying time.

The next day I thoroughly buff the entire surface (including the backs and bottoms of furniture which I finish to balance the piece and maintain equilibrium with 4 OT (0000) steel wool. This is the finest grade and I find that it really smooths the surface. After removing the steel wool dust, I apply the first coat of Arm-R-Seal gloss. As a rule I always build the finish with coats of gloss whether it is oil, lacquer, urethane, etc. Then, if I want a semi gloss or satin sheen, I’ll use that for the last 1 or 2 coats. Keep in mind that the Arm-R-Seal dries faster so I usually just work smaller areas up to 12 square inches and overlap the finish. Again, I brush it on, let it soak in for a minute and rub the surface dry with a clear cloth. Let it dry and repeat the process.

I find that a total (including the sealer coat) of 4 or 5 coats usually creates a nice smooth finish that protects the wood while bringing out the beauty and depth of the grain patterns.

I learned from watching David’s show about tung oil finish. He used it on almost everything he made back then. I have used it on most of my wood items over the years, and have found it to be easy to apply, and durable. My polychromatic or segmented bowls are all finished with it. It also brings out the grain and texture of the wood. The brand I have had great success with is Minwax Tung Oil Finish. I sand to at least 220 grit, and then apply several liberal coats of tung oil wiping of the excess about 30 minutes after application, and then letting each coat dry over-nite before applying the next. Minwax Tung Oil is easy to find, is not too expensive, and can easily be used to refinish the piece in the future.

I also recently found a homemade formula for wood finish that you can make yourself to save money, or to get the exact finish you want. It is a thinned varnish topcoat. It is a 50/50 mix of varnish and mineral spirits. It can be easily wiped on with a soft lint free cloth to fill in high and low grain differences. For best results you need to lightly sand in between coats, letting each coat dry completely before applying the next, and you will probably need to apply at least two coats for good results. Most store bought wipe on poly finishes are just a 50/50 mix of varnish and a solvent agent such as mineral spirits.

Another so called homemade finish is thinned shellac. Shellac can be purchased in flakes, and stored dry until needed. It is usually mixed with denatured alcohol. Because alcohol is used, it drys very quickly. You can custom blend the shellac to achieve the correct color. Because it is mixed by you when needed, only the amount you intend to use for each application is mixed, therefore maximum economy is reached. Shellac has been used by woodworkers since the early 1800’s. It is non-toxic, can be used as a sealer before applying a stain (to even out the stain’s application), can be custom mixed with nearly any color, and is very easy to use to refinish the item in the event of damage of the surface. After the first coat of shellac dries, lightly sand with 400-grit. Wipe off the residue and apply a second coat. Repeat until the desired number of coats have been applied.

This direct application will result in a high-gloss finish. If a less glossy, satin finish is preferred, try buffing out the final coat with some 0000 steel wool and (non-silicon based) paste wax. Lightly work the wax over the finish until it is thoroughly covered. Allow the wax to dry, then wipe off and buff to a lustrous finish.

I have never used Shellac so I can not recommend it. Technology has come a long way since the 1800s in just about every aspect of our lives especially woodworking. In my experience the quick and easy approach to woodworking tasks allows you to accomplish more, and be more productive in the long run. That being said, a gorgeous finish can really make a piece.

I have also used Watco Danish Oil Finish on a lot of items I have made. Danish Oil is basically a wipe on oil based finish that you can buy in numerous colors. It stains, seals, and protects in one step. It also comes in clear finish. Like Tung Oil, it is easily applied coat by coat until the desired finish is reached. But unlike Tung Oil it also stains the wood changing or enhancing the color. I have used it mostly on furniture that I have built. The thing that I like about it especially for furniture is that it can be used to smooth out imperfections in the wood, and can be used in the future to refinish the wood when repair is needed in the surface. It says on the can that it hardens in the wood, not on the wood. I have found it to be extremely durable and the surface holds up well to day to day use. The mission style living room coffee table and end table that I made, my computer stand that I made, and my 58 year old Walnut Office Desk are all finished in Danish Oil.

Preparing the Finish

As you prepare to finish, you’ll find that paint thinner can be used to cause defects to show up before the finish is applied. What you see with a wet coat of paint thinner is what you will see with a finish. Blotches, scratches, glue spots, and other flaws are easily detected. Paint thinner evaporates fairly quickly and leaves no contaminant on the wood. You can use any kind of finish without problems, after the thinner dries.

If you see scratches or machine marks from sanding, you might not have sanded adequately with your last grit of paper. Re-sand, and check again. If you still find prominent scratches, go to the next finer grit, and sand the wood thoroughly once again. This can not be stressed enough! The sanding process is one of the most important yet least understood aspect of wood working. The hard work you put into this step pays huge dividends in the end product.

Woods with fine pores, including pine, cherry, birch, and maple, tend to blotch when stained. This uneven coloration is a result of variations in the density of the wood. Anything put on the surface tends to absorb more in the softer areas than in the harder areas of the wood. The greater the absorption, the darker the color. I have also found that quartersawn Oak has a tendency to blotch and some times lighter areas of the wood actually get lighter after stain is applied.

Whether it’s due to normal squeeze-out or an unnoticed drip, dried glue will produce an unsightly spot in the finish. Once the glue starts to set scrape it off with a sharp blade, and wipe the wood with a damp rag. If they show up after you have applied stain or a topcoat, you’ll have to re-sand the area to remove them.

Wood conditioner can be used like a thin film of finish to block stain from over-penetrating porous areas. It partially fills pores and evens out the surface. You can buy ready-mixed wood conditioner or make your own by mixing two parts mineral spirits to one part polyurethane or alkyd-resin varnish. To apply conditioner, brush it onto the surface and allow it to penetrate thoroughly. Then wipe away any surplus, and let it dry overnight. Lightly sand the surface with 220 grit, wipe clean, and apply stain. I have found that Minwax Pre-Stain Wood Conditioner, and Behr Classic Oil Pre-Stain Conditioner both work well if you don’t want to mix your own.

For the most consistent color, even between wood parts of different shades, apply stain to a layer of film finish applied after sanding, instead of the bare wood itself. Brush on or spray the sealer evenly across all surfaces, and allow it to dry. Scuff-sand the surface with 220 grit, and apply the stain. The sealer does make it more difficult to achieve dark stain colors, but it eliminates blotching and lessens grain contrast.

There are many water-based finishes on the market. In my experience water-based components are not as durable or eye catching as oil-based finishes. They are however, much more forgiving of brush strokes or slight wood imperfections. Because I do not use them, I can not recommend them. If any of you readers have had either good or bad experiences with water-based products, please post your comments so the rest of us can learn from your experience.

Always test out the stain or finish on a piece of similar scrap wood before applying it directly to your wood creation. You can also use this process to get just the shade or color you want for the final look. Once stain or finish are applied, it is hard to go back and remove. In most cases it must be sanded completely off to bare wood again to avoid blotches or spots in the final product. Once you have developed your own tried and proved method, you will be able to predict how a certain stain or finish will look on your final product.

I hope this information will help you to make a decision on what kind of finish to apply to your next woodworking project. If you would like to take a look at some of my wood projects that I have for sale please take a look at my etsy site. Please email me with any comments or questions that you might have. Please feel free browse the entire website and read my other blog posts.

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