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This article is from Issue 12 of Woodcraft Magazine.
Armed with the information in this article, you can build a perfect finish in a weekend. To test your newfound finishing skills, make a Shaker serving tray.
It isn’t easy to build a perfect finish, but it is simple. Unlike other more complex woodworking disciplines which can be mastered only after years of study and practice, the construction of a perfect finish can be mastered in a single weekend. It only takes a few hours. And the best part is that everything you absolutely must know to build a perfect finish is right here on these pages.
I don’t mean that after reading this brief article you will know how to successfully apply every finishing product on the market. Some require months of study and practice to master, but if you follow the suggestions I present here, you will know how to apply a class of widely available products in a way that will produce near-perfect results every time you use them.
Twenty-five years ago, when I discovered the Sam Maloof finishing mixture of equal parts polyurethane, boiled linseed oil, and mineral spirits, my finishing practices were revolutionized. Finally, I could eliminate the problems of dust motes settling on surfaces to which I had applied spray-on or brush-on finishes. It was a problem that had plagued my work since I took my first fumbling steps in the workshop late in the 1960s.
I could apply a coat of the Maloof mixture, wipe it off, and then run a table saw in the same room. And no dust would stick to the newly finished surface.
For the next 15 years, I applied this finish with consistently good results. Then, maybe 10 years ago, I teamed up with a friend to build a set of dining room furniture. He was building a curly maple huntboard and dining table, and I was building the eight curly maple chairs to match. I wanted our finishes to have the same look, so I asked my friend what he was going to apply. Waterlox, he said. So I tried this tung-oil product and liked it very much. For the next eight years, that was my primary finish. Like the Maloof mixture, it was a wipe-on, wipe-off product that was immune to dust incursions, and it had the advantage of coming to me ready to use. I didn’t have to keep three products on hand and then mix them when I was ready to finish.
Although I like working with Waterlox, it does have one glaring shortcoming. The product sometimes solidifies after even brief exposure to the air. If you use only a third of a can during one finishing session, and two weeks later you reach for that can in order to use the remaining two-thirds, it is likely to have congealed into a solid lump at the bottom of the can. This circumstance led me to my next finishing product.
One day, when I discovered that the only can of Waterlox in my shop had solidified, I picked up a can of Minwax Wipe-On Poly at Lowe’s, and found that it had very nearly the same working properties as Waterlox. Two coats — sometimes three — built up to a surface that was pleasing to the eye and felt good under the hand.
More recently, I’ve been using Gel Topcoat produced by General Finishes — also available from Woodcraft — with the same result. Two or three coats give me a nicely filled and leveled surface, one that has a satisfying satiny luster and a silky feel.
Although I recommend all the products I’ve mentioned here, Gel Topcoat has one appealing characteristic not shared by the others: Because it’s a gel and not a liquid, it doesn’t seep into joints to later bleed out as the finish dries.
Liquid products, like Minwax Wipe-On Poly and Waterlox, penetrate into the tiniest gaps in joinery. Over a period of hours, as the finish cures, the excess seeps out, making it necessary to rewipe those areas in order to avoid an unsightly buildup. Gel Topcoat doesn’t penetrate. Because of its gelatinous consistency, it stays on the surface where I want it to stay.
I should mention that I’ve grouped these products in the same arbitrary category, not because they share any chemistry. I group them together based on style of application. All these products are applied in the same way, and all produce consistently appealing finishes, so in my mind, they all belong in the same category. I apologize to any chemists who might be reading this.
Applying the perfect wipe-off finish
There are only two secrets to the construction of the perfect finish I’m going to describe here. One is thorough surface preparation: sanding. The other secret is careful wiping technique.
When I talk about sanding, I mean hand sanding. While it is possible to get good results with power sanders, I think it’s much easier, particularly for inexperienced craftsmen, to get good results with hand sanding. Too often, power sanders create more problems than they solve. Belt sanders often cut unsightly grooves in the work. And vibrating, oscillating or orbiting sanders can leave behind scratches that can only be removed by doing handwork in the direction of the grain.
We’ll start with surface preparation. This involves the use of a good smoothing plane and a minimum of four different grits of sandpaper: 100, 150, 220 and 320.
When stock comes out of your thickness planer, it has a gently rippled surface. The height of those ripples is determined by the speed at which work is fed past the knives and the depth of cut those knives are set to take. The surface will also likely have some areas of tearout. A slow feed rate and a shallow depth of cut will minimize but not eliminate these problems. All stock exiting a thickness planer will have ripples and tearout, even if those features are so faint they can be seen only under magnification.
The first step in creating a perfect finish is the removal of the ripples and the tearout. The weapon of choice for this task is a good, well-tuned smoothing plane with a sharp iron and a tight mouth.
With your smoothing plane, take light passes working in the direction of the rising grain.
If you don’t have a good smoothing plane, move directly from the planer to Step #2. (The use of a mediocre smoothing plane can actually create more problems than it solves, by tearing out reasonably clean surfaces.)
Most good craftsmen sand their work through a succession of grits, starting with relatively coarse paper which removes stock quickly (but leaves behind deep scratches) and following that with progressively finer grits, each of which removes the scratches left by the previous grit. You could theoretically start with the fine grit with which you intend to finish, but it would take several lifetimes to smooth a tabletop if you went directly from the planer to, say, 320-grit.
The specific grits in that succession will vary from craftsman to craftsman. For instance, I begin with 100-grit paper and finish with 600-grit paper. I know some very good craftsmen who start with 150 and end with 320. Personal taste plays a role in choosing your own path. Some woodworkers recognize that their clientele simply won’t value — or pay for — the extra labor required to sand a piece with 600-grit paper.
The grits in a succession will also be determined by the application. If I’m putting casing around our entrance door, I won’t sand that casing all the way to 600. I might stop at 320 or even 220.
If you decide to try the little finishing exercise I’m outlining on these pages, you will be able to judge for yourself what grits you need to use in preparing your work for that first coat of finish.
You’ll need a set of hardwood tiles approximately 3" wide and 4" long. The hardwood should be dense and tight-grained. Cherry or maple would be good choices for this exercise. I choose cherry because I have a lot of cherry scrap in my shop. Ring-porous woods like oak, which have long open pores even when they’ve been thoroughly sanded, won’t give you an accurate reading of how sanding with the various grits can affect the final result.
Plane each of the hardwood samples flat. (It’s easier to plane one long board and then cut the samples to length from it.) Be sure to work in the direction of the rising grain.
Cut a sanding block measuring
1" x 2½" x 3½" from a bit of softwood. Form a radius on the corners adjacent to the block’s top surface to make the block more comfortable in your hand. Tear each sheet of sandpaper into six equal sections. Each of these sections should cover the bottom of the sanding block with enough paper lapping the right and left side for your fingers to pin the paper against the sides of the block.
After you’ve taken a couple of passes with your first sandpaper grit, inspect each sample in a strong side light, tilting it this way and that to check for areas that might have torn out under the plane or planer. These areas will appear lighter in color because sanding dust pools inside them. Be sure to sand with the paper wrapped around your sanding block. If you use sandpaper held in your fingers, you’ll sand furrows into the surface that will be very difficult to get out. It does take longer to sand away tearout when you’re using sandpaper wrapped around a block because you have to lower the entire surface you’re sanding to the depth of the tearout, but the results are always better if you make this effort.
When any torn-out areas have been leveled, sand each tile for an additional 60 seconds with 100-grit paper wrapped around the block, taking great care to hold the block flat against the tile. Work in the direction of the grain. Give special attention to the ends of the top surface of each sample. Insufficiently sanded areas are often found in the half-inch of top surface leading up to the end-grain arris (angled edge). Refresh your paper at least once in the process of sanding the five samples.
Don’t cheat on the time. Do the whole 60 seconds. Most unsatisfactory finishes are the result of insufficient sanding. Mark Tile #1 “100-grit” and set it aside.
Sand the remaining tiles for 45 seconds with 150-grit paper, and mark Tile #2 as “100 and 150.”
Sand each of the remaining tiles with 220-grit paper for 30 seconds working in the direction of the grain, changing your paper at least once, paying special attention to the ends. Mark Tile #3 accordingly, and continue with 320-grit to create Tile #4.
Even though I recognize that many fine craftsmen don’t take this final step in surface preparation, I’m going to suggest that you rub out the final sample with 600-grit paper for 30 seconds working in the direction of the grain, paying special attention to the ends approaching the arrises. Mark this sample 100, 150, 220, 320, 600 (Tile #5).
If you’ve conscientiously followed each step, you’ll notice that the wood sanded with the finer grits has developed a soft sheen, almost as if a coat of finish has been applied. In fact, it’s possible to apply a coat of paste wax to a surface that has been prepared in this way. Although by itself wax doesn’t offer much protection, it will buff out to a very nice luster on raw wood.
Following the directions on the can, apply a coat of wipe-off finish to all the samples, including those that received only coarse sanding. Wipe it on with a rag. Then wipe it off.
The removal wipe is important. You should wipe thoroughly but not scrub. Leave a film only a few molecules thick. (I’ve never actually counted molecules, but I think it’s helpful to think of the wiped finish in this way.) Any areas on which there is extra finish will dry rough and pebbly. But you don’t want to scrub the surface dry because if you do, there won’t be enough finish left to fill the surface, and an unfilled surface won’t have the leveled sheen that is the hallmark of a good finish.
The wipe should be done with an absorbent and lint-free fabric. I find old T-shirts are just about perfect. White T-shirts are best because they don’t contain any dyes, but any T-shirt without screen-printed graphics will probably work. You can’t use fabric with screen-printed graphics because the solvents in the wipe-off finishes will dissolve the paint in the graphics, leaving colored smears on the work you’re wiping. If you’re not sure about the dye in your T-shirt fabric, experiment on scrap before using it on the good stuff.
Allow the finish to dry overnight. Then sand lightly with 600-grit paper to remove any grain raised by the first coat of finish. Sand only long enough to smooth the surface; 10 seconds may be enough. Test the smoothness with your fingers. Then apply a second coat of wipe-off finish using the same method you used for the first. This second coat should dry smooth because you’ve sanded away the raised grain. If it doesn’t dry smooth, re-sand with 600-grit paper and apply a third coat of wipe-off finish.
Take some time to study the completed tiles. Observe the differences in luster and tactile refinement between the sample sanded with 600-grit paper and the sample sanded with only 100-grit paper. Then compare the 600-grit-sanded sample to each of those sanded with intermediate grits. In this way, you can make an informed decision about how much preliminary sanding you feel is appropriate for specific applications.
I didn’t apply any wax to the samples (or the serving tray) I finished for this article because I wanted to develop surfaces using the primary finishing material. (It is possible to hide some finishing problems under a good coat of wax.) Nevertheless, when a situation calls for a glossy sheen or the tactile quality of wax, I top off my finish with a coat of good paste wax. I use a Minwax product called Finishing Wax with very good results — although contrary to what many craftsmen think, those very good results are not easily achieved.
It’s pretty tricky to get a good wax job. Areas on which there isn’t enough wax won’t buff out to a sheen no matter how hard you rub, and areas in which there is too much wax won’t buff out properly either. These areas with too much wax will always remain a little pebbly. Only those areas on which you’ve applied a consistently thin layer of wax will buff out to the proper sheen.
And it can be very difficult to properly apply that consistently thin coat of wax.
Most finishers apply wax using several layers of cheesecloth in which they’ve nested a ball of wax. They rub the cheesecloth over the surface to be waxed, and the wax penetrates through the openings in the cheesecloth leaving behind — theoretically — an even layer of wax. I’ve tried this method, but I’m more comfortable with my own.
I simply wad up a bunch of lint-free fabric (once again T-shirt material is my favorite), dab it into the wax can until the bottom of the wad is covered in a layer of wax — think a thin spread of margarine on a slice of toast — and wipe the wax onto the surface.
Before I allow the wax to dry, I hold up the surface to a good side light to check my coverage. If I don’t have the consistently thin layer I want, I load up my fabric wad and rewax. The solvents in the wax will reliquefy any wax from the first coat that might have dried.
This is pretty simple on a flat surface like any of the tiles you’re preparing, but it becomes much more difficult with an actual piece of furniture. Chairs, for instance, (which constitute much of the work coming out of my shop) are particularly difficult because there are rungs sprouting from the posts every few inches.
Kerry Pierce is the author of a dozen woodworking books and more than 60 articles for woodworking magazines. His most recent book, “Authentic Shaker Furniture,” was the main selection of the Woodworker’s Book Club.
SHAKER SERVING TRAY
I’m currently working on a book about the furniture produced at the Pleasant Hill Shaker community near Harrodsburg, Ky. During the two trips I made to Pleasant Hill to research that book, I spent a lot of time crawling on the floor, looking at the undersides of tables, examining construction details, taking note of the marvelously efficient assembly methods used by the Shakers. Those methods included the widespread use of nails in applications that some furniture makers might see as inappropriate.
This little serving tray, based on a Shaker original drawn by Ejner Handberg, illustrates this use of nails. In addition to the hand-cut dovetails at each corner, this tray employs nails driven through the sides into the edges of the tray bottom and up through the bottom into the tray ends.
This simple piece can be built in a single weekend. Begin by gluing up the wide panel needed for the bottom. Then, as that is drying, rip out and cut to size the two ends. The handholds are formed by defining the ends of each with a ¾" Forstner bit, then connecting those two holes either with a hand-held saber saw or a jigsaw. Next cut the dovetails that join the tray frame. I cut mine by hand because that’s the only way I know how, but I’m sure they could also be cut quickly using a router and jig.
Before the parts are assembled, it’s time to sand. The inside surfaces of each part must be sanded through the entire succession of grits. I recommend you sand all the way to 600-grit, but you should go at least as far as 320-grit. The outside surfaces can be sanded later after you’ve planed the dovetail pins and tails flush. Be sure to use a sanding block to back up your paper.
Some furniture makers take this process a step further by finishing the inside surfaces before assembly, and while I might do that with a more complicated construction — like the pigeonhole assembly for a desk — for a piece like this, into which it’s very easy to get your hand and wiping rag, I choose to finish after assembly.
Glue up the dovetails, and bring the four sides together. Check the frame for square by measuring the diagonals. If they don’t measure the same, rack the corners connecting the longer measurement until the measurements are identical.
As I said, the bottom — like the bottom on the Shaker original — is held in place with nails, and if you haven’t driven nails into hardwood, I should point out that this is a process that should be approached cautiously, because it’s easy to split hardwood with nails. Fortunately, it’s just as easy to avoid this unhappy outcome if you do a little preparation. The stock through which the nail will pass first must be drilled with a bit that is nearly the same diameter as the nail you’ll drive into that hole. Then the stock into which the nail will ultimately be driven must also be drilled, this time with a bit that’s just a little smaller than the first bit. Remember, the nail needs to seat itself securely without splitting the stock
I used 6d finish nails through the sides of frame and 6d common nails through the bottom where the heads wouldn’t show. I would give you the bit diameters of the bits I used, but there is a fair amount variety of shank diameters in 6d nails, so I would suggest that you experiment on scrap until you get holes that allow the nail to get a grip without also splitting the stock.
When you’ve selected the right bits, fit the bottom into its place, and drill the through holes with the larger of the two bits. Then, with the second (smaller) bit, drill holes that penetrate as deeply as the set nail will penetrate. Then drive the nails using slow, controlled blows of your hammer. The photo above shows the joinery at one corner as well as the heads of the 6d common nails on the tray bottom.
Once the piece is assembled and the nails set, you’re ready to prepare it for finishing. Begin by leveling the pins and tails at each corner with a good plane. This is work for which a good low-angle plane was designed, but a good smoother will also work quite nicely here.
Then sand the exterior of the piece, again working through the whole succession of grits in the direction of the grain using a sanding block to back up your paper. The top edges of the ends and sides can also be done with a block except for the areas right up next to the ends. This is best done with a bit of folded paper held in your fingers. The hand holds will take some effort to sand. Again, here you must work with a bit of folded paper held in your fingers.
Because you will have a natural inclination to apply pressure to the inside and outside edges of these hand holds, concentrate on applying pressure in the middle of the stock. This should result in a sanded surface that is flat across it's width.
Apply finish with a bit of wadded up T-shirt fabric. Carefully wipe away the excess. Let the finish dry. Then rub it out with 600-grit paper and apply a final coat of finish. If the surface isn’t sufficiently filled and leveled, sand and apply one more coat.
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