Plywood is about the most popular wood product on the market. The various grades and types of plywood available make it possible for woodworkers to do just about any project they want, strictly from plywood. When used in conjunction with solid hardwood boards, there’s almost nothing that can’t be built.
The problem with many plywood projects isn’t making the project itself, as plywood is stable and easy to machine; but in finishing the plywood in such a way that looks good. Well finished, plywood can look as nice as any other wood; but if it’s poorly finished, people can tell.
Proper finish starts with selecting the right plywood, especially the plywood grade. Lower grade plywood, especially construction grade plywood, is not designed for fine finishing; but rather for use in places where it is not visible. For fine finish, start out with some quality hardwood. If softwood is desired, at least select a high grade of softwood. A-grade face finish is the only option for a good finish on softwood furniture made of plywood, while A and B grades work well for hardwood plywood.
The most common finishes used with plywood are paint and stain. But those aren’t the only options by far. Nor are we limited to only one way of finishing with paint and one with stain. There are other finish materials that can be used with these, as well as different techniques which will create special effects in our finish, even making plywood look like it is some other material.
A Really Smooth Varnished Finish
By and large, most people think of a stained and varnished finish as being a finer finish than a painted one. We all enjoy the natural beauty of wood and like to let it shine through whenever we can. But not all stained and varnished finishes end up looking good, mostly because people try to rush through the process, rather than taking the time to properly prepare the surface and apply the finish properly.
Creating a smooth finish is actually more about sanding, than it is varnishing, although varnish is used. Nevertheless, quality finishing materials, which provide high build-up, are important to achieve the kind of high-grade finish that’s likely to impress people.
Start by sanding the entire surface with 220 grit sandpaper, smoothing the entire surface of the project, while taking care not to sand through the face veneer. Hardwood plywood will often have very thin face veneer, 1/40th of an inch thick, so care must be taken. Some sanding with coarser grits may be necessary, before 220 grit is used, but the final sanding should be with 220 grit sandpaper, removing all scratch marks from sanding with coarser grades of sandpaper.
Clean off sanding dust with a vacuum cleaner and then wipe down the project with a damp cloth to remove any dust remaining. Be sure to clean off the workbench or finishing area as well, removing dust that could end up in the finish.
If a stain is going to be used, this is the time for it. By and large, stains don’t affect the smoothness of the surface, although they can lift the grain, especially if the stain is allowed to dry on the surface, rather than being wiped off.
Once the stain has had ample time to dry, apply a quality wood grain filler or sanding sealer. Wood grain filler or paste wood filler is used on open grain woods, such as oak, to fill the pores in the grain. Once it dries to a putty-like consistency, the piece should be rubbed down with natural burlap, removing the excess filler and only leaving it in the pores of the wood. Then the sanding sealer should be applied. This acts as a primer does for paint, sealing the surface pores, so that the varnish doesn’t soak in.
Sanding sealers are usually fast-drying, so it can be lightly sanded with 220 grit sandpaper after about one-half hour. Wipe off the sanding dust with a tacky cloth.
The project is now ready for the polyurethane finish. Floor finish is thicker than other polyurethanes, providing a heavier coat. Brush it on with a good natural bristle brush or foam brush, being careful to avoid any drips or runs.
Once the polyurethane finish has dried, hand sand it lightly with 220 grit sandpaper to remove any bumps, especially where particles of dust settle in the finish. These will feel almost like grains of sand, when you rub your hand over the surface of the project. Wipe off the sanding dust with a clean, tacky cloth.
Repeat the application of polyurethane as many times as necessary to build up a finish as thick as you would like, sanding lightly with 220 grit sandpaper between each coat.
Once the finish is thick enough, sand the finish lightly with 400 grit sandpaper, and then with 600 grit sandpaper. This will smooth out the varnish, providing a perfectly flat surface, hopefully without defects. For the final polish, buff the finish with a good quality carnauba wood floor wax.
Painting for a Smooth Finish
No painted plywood project is going to look as good as varnished will; but there are times when paint is more appropriate. As with staining and varnishing, the key to a good painted finish is proper surface preparation, sanding the surface smooth and flat, working through the grits of sandpaper down to 200 grit.
Once the plywood is sanded smooth, vacuum and then wipe of any remaining dust, cleaning the surface and the work area around the project. Any dust left behind is likely to find its way into the paint, so it’s good to remove it.
Prime the surface of the wood with a fast-drying primer-sealer and allow to dry. Some primer-sealers will dry in as little as 30 minutes, allowing you to go on with the finish work.
Running a hand over the surface of the project is a great way to tell how smooth it is and whether any grains of dust got into the primer. If they did, a light sanding with 220 grit sandpaper will knock them down, allowing the finish process to continue. It isn’t necessary to apply a second coating of primer, unless the project requires enough sanding to make the plywood visible again.
High quality paints will have a higher percentage of solids, allowing them to build thicker coats of paint. That not only covers better, but will also work to provide a smoother, more durable finish. Even so, the biggest problem in painting such projects is the elimination of brushstrokes. Working with a high-quality brush can help; natural bristle for oil-based paints and nylon for water-based paints. It can also help to add the product Pentrol to the paint, when using oil-based paints and Floetrol when using water-based paints. These products help the paint to flow out, smoothing out brush strokes.
It shouldn’t take more than two coats of paint to cover any project, as long as high-quality paint is used. However, a third coat will often help to hide the grain and any irregularities in the paint itself, providing a smoother, more even finish.
Making Plywood Walls Look Good
At times, it can be useful to cover walls with plywood, rather than covering them with drywall. Plywood is considerably stronger, so when there is a need for a more secure wall, that someone could not punch through or when dividing a workshop from a living area, it might be advisable to cover the wall with ½” AB grade plywood, rather than sheetrock.
The problem is that painted plywood tends to look like painted plywood, especially when it is used on walls, right next to drywall. The secret to getting it to look the same as the drywall, is to start by taping the plywood, just like you would with drywall. Then, skim coat the entire plywood surface with drywall mud and then sand it smooth. Once textured and painted, it will look just like the rest of the walls.
How to Stain a Plywood Floor
Wood floors are normally hardwood or laminate, laid over a plywood substrate. But hardwood flooring is expensive. So some people might need to wait before installing it. There might also be situations where the plywood is left, without covering it with hardwood flooring, because a wood floor is desired, but it is in a part of the home where appearance is not all that critical.
In that case, the plywood subflooring can be stained and varnished, creating a faux wood floor. This only works if a good grade of plywood is used for the floor. It won’t look good with a C or D grade plywood; but will look okay with a B grade surface showing. Many times the cost between BC and CD plywood is minimal, so this is not unrealistic.
Before applying any finish to the floor, sand it smooth, paying particular attention to the edges where sheets of plywood come together. Then be sure to clean up all the dust, wiping the floor down with a damp cloth.
Normal wood stain can be used on plywood floors, but it is best to dilute it 50/50 with mineral spirits. The amount of tint that is normally added to wood stains is rather high, as it is intended to be applied and then wiped off. But rather than wiping it off, we’re going to wipe it into the wood grain.
To apply the stain, use a rag, dipping it into the can of stain and then rubbing it into the floor. This saves the mess of removing excess stain and provides a uniform finish.
Once the stain has had time to dry, the plywood floor can then be covered with two coats of a heavy-duty polyurethane floor finish. For best results, apply it with a foam roller or brush.
Texturing Plywood to Age It
For most applications, a smooth surface is desired. But that’s not the case when a distressed look finish is being applied. In that case, a rough finish is advantageous, as it makes the wood look naturally aged. Take a look at the surface of an old wood privacy fence sometime; the surface will be rough, as if part of the wood fiber is worn away.
This look can be created artificially on perfectly new plywood, providing a great surface for painting and applying the antique finish to. All it takes is a corded drill and a brass wire brush for the drill. A cupped wire brush will work better, although a flat round one can be used as well. However, the flat round brush or a steel wire brush, will be more aggressive on the wood than the brass cup brush will.
All that’s needed is to run the brush over the wood, covering the entire surface, while holding the drill at an angle, running at full speed. The wire brush will dig out the softer part of the grain, leaving the harder. For softwood (pine) plywood, this means digging out the lighter part of the grain, while leaving the darker.
Once the entire surface has been brushed from one direction, the board should be turned 180 degrees, the drill switched over to run in reverse, and the surface should be gone over again. This will provide brush marks that run crosswise to the original ones, making the artificial aging look more natural.
Caution should be taken while doing this, so as to not go through the face veneer. For this reason, this procedure doesn’t work well with hardwood plywood, which has a very thin face veneer. It does work well with construction grade plywood though, as well as for pine or whitewood boards.
Once the wood is textured, the wood can be stained and/or paints can be applied, either by brushing or rubbing them in with a cloth, to provide the desired antique effect. Most of the time two to three different colors are applied, to make it appear as if paint has peeled off, exposing older layers of paint underneath.
Making Plywood Look Like Steel
A number of differ special effects can be applied to plywood projects, making the plywood take on the appearance of other materials. One common material that is mimicked by plywood is steel.
Making Plywood Look Like Old Steel
The perception that the plywood is old steel can be accomplished by first priming the sanded plywood and then painting it with a couple of coats of aluminum colored paint, allowing the paint to dry between coats. If a grey primer is used, the paint will likely cover better, than if a white paint is used.
Once the paint is dry, the surface of the plywood can be “antiqued” by taking a clean natural bristle brush and putting just a little stain on the end. The idea is to be applying the stain with a “dry brush” technique. This is as if the brush had been used for staining and then the stain cleaned out as best as possible with paper towels. A little bit of stain will still remain behind, but not enough to lay down a coating anywhere.
With the dry brush like this, paint over all the edges, protrusions and seams, applying just enough stain to look like the steel is dirty in those areas. A full covering is not desired, but merely a dusting. Allow the project to dry and then cover the stain with a clear coat spray.
Making Plywood Look Like Black Steel
A very nice black steel effect can be made on plywood, very easily. Before doing so, sand the plywood smooth with 220 grit sandpaper and then apply a single coat of sanding sealer. Allow the sanding sealer to dry, and then lightly sand it with 220 grit sandpaper to eliminate any dust specks sticking up.
The first finish coat is actually black putty, not paint. This should be scraped onto the surface of the plywood, across the grain, with a putty knife, scraping off any excess that doesn’t go down into the wood grain. While the idea is to cover the entire surface, it doesn’t need to be perfect. Rather, it is best to leave some bare spots, so as to give the project a more aged appearance when finished. Scrape the surface a final time with the putty knife, to remove any excess. Then allow the putty to dry fully, before proceeding.
Tinting of the wood is accomplished by rubbing on India ink. This needs to be purchased from an art store, as they are probably the only ones who have real India ink. It is a permanent ink that is not water-based. If anyone offers a water-based product, it’s not the real thing.
The problem with working with India ink is that it stains badly; clothes, workbench tops, hands, and anything else it comes into contact with. So care must be taken to cover the benchtop and wear rubber gloves when working with it. Wear old work clothes, just in case.
Rub the Indian ink into the wood with a cotton rag, wiping off any excess. The India ink will stain the wood rapidly, turning it totally black. Together with the wood putty, it will provide a mottled black appearance, almost a black on black, which will look like old black steel.
Making Plywood Look Like Marble
A slightly more complicated process allows plywood, such as plywood countertops, to look like marble countertops. This is a technique which has come out of using epoxy resin with wood. A slow curing epoxy is needed, one with a working time of 24 hours or so.
The surface is first covered with Bondo (automotive body putty) to fill in the edge grain and any imperfections in the surface. On the edges, a putty knife can be used to create texture, by placing it on the Bondo and then pulling it away. This will cause peaks in the Bondo. Once the Bondo cures, it is sanded smooth, with the exception of the edges, which are sanded enough to remove the peaks, but still left rough, as if they represent the rough edges of the stone slab.
The surface is then painted with a couple of coats of primer/sealer of a color that is compatible with the finished color desired for the countertop. If a white marble look is desired, then use a white primer; black for black. For every other color, use gray primer, as it will blend best with the other colors used.
The key to this surface finish is the application of the two-part epoxy, which is poured onto the surface and then leveled with a ¼” notched trowel, the same kind used for ceramic floor tile. Then paint brushes are used, stabbing into the resin, all across the surface, breaking the surface tension and creating an uneven surface to work with.
Now it’s time to apply the colors. This is the crazy part; but it’s highly effective. First, metal dust is sprinkled or sprayed across the surface, giving it a light dusting. Then spray paint is used to apply coloration. Take the various colors of spray paint and paint sloppy lines, all running in the same direction, across the entire surface. Don’t cover the entire surface; just make a bunch of lines.
The colors used for this should follow a theme, allowing for the final coloration of the countertop.
- If a white marble look is desired, then spray white, with a little bit of black, grey and possibly a tiny bit of brown
- If a black marble look is desired, then spray black, with a little white and grey.
- If a turquoise marble look is desired, then spray a couple of shades of each blue and green, along with a little bit of yellow and a touch of black.
Taking a paint paddle and laying it on its side, move it back and forth, across the direction of the painted lines, as if were a trowel, making short strokes to mix the paint and metal dust into the epoxy. If bubbles form, run the flame of a plumbing torch across the surface to bring the bubbles to the top and pop them.
At first, the countertop will look horrible, like someone made a big mistake or a first grader messed with the paint. That’s normal. Continue adding applications of metal dust and spray paint, working them back and forth, mixing the colors together. Each time additional paint is added and then mixed, the mixture becomes more complex and random, until it reaches the appearance of natural stone.
Once it has reached that point, allow the rosin two days to fully cure, and then coat it with another layer of epoxy, allowing that to cure fully before the countertop is used.