Perfect Finish

Not too long ago, a group of woodworkers asked me what could be done to streamline their finis They were plagued with an ever-expanding horde of chemicals and equipment and wanted to cut back. Was there a finish and a finis And my answer was yes, there is, but you have to find it. Years ago, Interviewed the renowned turner, Rudy Osalnik, for a woodworking magazine. Rudy taught wood arts at Berea College. I was looking around at When I asked Rudy about t He shared it with me, and I've been using it ever since. Before Rudy, I must have tried a hundred different finishes, and when I wrote my finis Let me show you somet T And that's after I cleaned it all up so you folks wouldn't be totally tra I've got the feeling that if ever I was to take all of the point is, there are many, many ways to finish wood, and there are more being invented every day. T If you were to choose just one finish, how could you possibly know that you're making the right choice? Well, there is a way. Rudy didn't share just He showed me how he arrived at Let'start with a quick review of why we finish wood. There are just three reasons. Protect the wood, reduce the absorption and release of moisture, and beautify the wood. Let'start with protection. Wood is a fiber, and fibers get dirty. They absorb grease, oil, water, all sorts of chemicals. A finish seals the wood. It makes it easier to clean and to keep it clean. It also hardens the surface, protecting against scratches, wear, and abrasion. A finish slows down the exchange of moisture. The moisture content of wood changes with the relative h A finish reduces t It does not stop it completely. Finishes are semi-permeable, allowing the moisture to pass slowly. But it stops rapid movement and reduces the stress on the wood. And finally, it makes the wood nicer to look at. Typically, a finish warms up the wood, making it darker and slightly more yellow. It also brings out the grain by emphasizing the difference between the dense s A good finish makes the wood translucent. Let me show you what I mean with t In fact, t Without a finish, it does a fairly good job of blocking the light. But if I apply a little finish, the light goes right through. The same the fibers near the surface become translucent and may make the finish look deep. And that's what we're trying to ac And we ac We coat the wood with a chemical that protects it, reduces the exchange of moisture, and makes it pretty. These chemicals are diverse and complex, as my finis But everyt The solids are normally resins, and the carriers are solvents. You dissolve the solid in the solvent and paint the mixture on the wood. The solvent dissipates, leaving be Back when we first began finis Today we refine resins from organic fats, oils, and petrole All with different characteristics. You're There are four different ways that these resins can form a coating. You have evaporative finishes, such as shellac or lacquer. After applying the finishes, the solvent evaporates, leaving be The trouble is, t Reactive finishes react with the oxygen in the air. The solvent evaporates, and the resin that's left be It's easy to put on multiple coats because once reacted, the finish can't dissolve itself. T Catalyzing finishes react with a hardener. Often, the resin is its own carrier. It exists in liquid form until you mix it with a hardener or a catalyst, and then you have a limited time to apply it before it hardens. The good the bad t And finally, we have coalescing finishes. These came about in the second half of the 20th century when folks became concerned about all the chemicals that were letting evaporate into the air we breathe. The carrier is mostly water, and suspended in that water are tiny little droplets of a very powerful solvent that is saturated with a partially reacted resin. Apply the finish, the water dissipates, and those droplets coalesce into a t As the second solvent evaporates, the resins harden into a chemical matrix. There are very few finishes for w They just soak into the wood and provide some, usually just a very little, protection and beautification. These are almost always non-toxic oils, and they are preferred by some for finis These are called non-drying or non-hardening finishes. Now You're probably just as confused what to choose, but at least The next step on t Naturally, you want maxim That goes without saying. However, there are other factors. For example, how much time are you willing to take to apply a finish? How much equipment are you willing to buy? And what methods or skills do you need to develop in order to get the effect that you're after? Well, to answer these questions, it helps to t Finishes are normally applied in layers or coats, each coat as t And to do t You can wipe a finish on, you can brush it on, or you can spray it on. Let's talk about spraying first. T Not only do you need a spray gun and a compressor, but you have to have some way to evacuate the overspray, such as a paint booth with a fan ducted to the outside. Otherwise, the overspray hangs in the air and you either breathe it in or it settles on everyt And spraying takes skill. You have to be able to lay down a the equipment required for brus But t Brus But it's not a difficult skill to acquire. It just takes some patience and focus. By far, the easiest method is to simply wipe the finish on the wood. If there is any excess, you simply wipe it off. There is no expensive equipment to buy. All you need is a lint-free cloth. Although, I There are no special skills needed. You just need to be able to spot when a coat is too to be sure, there are some drawbacks. Because each coat goes on very t And because the coats are t It's also difficult to wipe a coat of finish evenly on complex surfaces. In these circ I brush the finish on, then I wipe it off with an almost dry brush, then I wipe the brush off on a cloth. So, for many of us, especially those of us who aren't in production woodworking, a wipe-on finish is the easiest way to simplify our finis T So, what kind of finish are we looking for? Well, there are definitely no evaporative wipe-on finishes, unless you want to t But that'so hard to apply, and it's not nearly versatile enough to serve as your go-to finish for a wide range of projects. And there are very few catalyzing wipe-on finishes. For the simple reason that part of the wipe-on process is wiping off, and these could be hardening before you get all the wiping done. So, what we're looking for is either reactive finishes or coalescing finishes. Wit You have non-drying oils, drying oils, wiping varnishes, and blends of all three. You should also consider other finishes that aren't necessarily designed to be wiped on. For example, if you have a brush-on varnish or polyurethane that you T And speaking of experimentation, that's where we're headed next. When I first asked about simplifying finishes, I thought, well, I'll just give them Rudy's recipe. After all, it's worked for me for 30 years. And then I thought, well, it has worked for me for 30 years. So, well, in fact, that I haven't really explored anyt Maybe before I give them the easy answer, I should cast around a bit. So I talked to some woodworking friends and I read some reviews to see what I'd missed. And there was quite a bit. The coating chemistry industry is a busy place, but I was able to w Some of these I'd never tried before. Others were old friends that I wanted to reevaluate. I've grouped these here according to their chemistry. Hope's Pure Tongue Oil is a non-drying finish, although it does harden after a week or more. Tried and true original wood finish dries a little faster. The finish is made from a pulmarized linseed oil and beeswax. Minwax Tongue Oil Finish is a blend of drying oils. I'm not going to get into the controversy of whether or not there's any real tongue oil in t General Finish's Wood Bowl Finish is another blend of drying oils made especially for use on kitchen utensils, but it's versatile enough to be used on other t Minwax Antique Oil is a blend of drying oils and varnish. It quickly builds to a hard luster. Minwax Wipe On Water-Based Poly is a wiping polyurethane varnish, and the only water-based coalescing finish that we have in t General Finish's Armor Seal is an oil-based wiping varnish. T If you'd If it wrinkles up at the edges, it's a drying oil. If it dries completely smooth, it's a wiping varnish. And if there's just a little bit of wrinkling at the edges, it's a blend. The advantage of knowing the tongue oil, the linseed oil beeswax blend, and the bowl finish all pride themselves on being non-toxic. But here's the secret. These are all food contact-safe once they are fully cured. In fact, all commercial finishes are food contact-safe. No one in the coating chemical industry wants you to have to go to the hospital for licking your dining room table. What about the safety data sheets? Well, I have them all right here. One for every finish, and they are fully terrifying. According to these safety data sheets, these finishes may cause headaches, skin irritations, psychotic episodes, brain damage, cancer, death, and that's just getting started. But these are written for people who apply the finishes, not those who use the finished objects. Once cured, finishes are relatively safe. But these data sheets are why taste tests are not part of the comparison. Incidentally, you can find the safety data sheet for almost any finish online. The manufacturers make them readily available. The problem is, they're not particularly informative. They're as dull as old shoes, and they purposely obscure what's in a finish in order to protect the formulas. In my book on finish, I wrote a section on how to read these t I've taken that section and I've posted it online free. The link is in the video description or it's hovering over my head. I evaluated these finishes for many different characteristics. And to help compare them, I scored them on a sliding scale of 1 to 5 with 5 being the good or more desirable side of the scale. The overall look of the finish. Just how attractive does it seem? How well does it warm the wood? Change its color from light to dark. How well does it bring out the wood grain in the wood? How easily can you build up multiple coats to give the finish some depth? How well and how deeply does the finish penetrate the wood? How hard and by extension how durable is the finish? How flexible is the finish? Will it expand and contract with the wood? Just how difficult is it to apply the finish to the wood? How long does it take to dry between coats? How difficult is it to rub or sand between coats? And finally, how does the finished object feel? I added to investigate these characteristics, I devised several experiments. I glued up strips of commonly available cabinet-grade woods. Chariot, maple, w And then I cut them into 12 inch or 30 centimeter squares. T By wrapping a piece of masking tape around the middle of each board, I divided it into four surfaces. T It also showed me how easy it was to apply the finish and how easy it was to sand between coats. And by looking at how much finish stuck under the masking tape, I could tell how well the finish penetrated. To limit the variables in t I wiped the finishes on with a cheap foam rubber brush and wiped them off with a lint-free cloth. I labeled both the brushes and the cloths so as to avoid cross-contamination. Now, two of the finishes required slightly different methods of application. And I adjusted my method to give these finishes a fair shake. And yes, I did read the directions on the can. I know t I also prepared all of the test boards in the same way. I sanded both sides, starting with 100 grit and working my way up to 220. Then I wet both sides and let the water dry. Then I sanded the grain again and knocked off the w Okay, let'skip ahead. You don't need to see me wiping and brus Suffice to say that I applied up to four coats to each surface and waited a day between coats for the finish to cure. Then I sanded it smooth with 320 grit sandpaper in preparation for the next coat. On two of the finishes, the tongue oil and the linseed oil beeswax blend, I waited a good deal longer between coats. And I rubbed them out with Scotch-Priate because the sandpaper loaded so quickly. For all seven finishes, I neglected to sand or rub out the fourth and last coat. I wanted you to see the final cured finished, untouched. Now I'm going to show you these finishes in a series of You can pause the video at any point to inspect a slide or you can download all the slides in PDF form from our general store. I've put the link in the video description or it's hovering somewhere over my left shoulder. Let'start with the softest finish, Hope's Pure Tongue Oil. It did an excellent job of warming the wood and bringing out the grain, but it did not build up in coats. It did penetrate quite deeply, but you can't see any build up. The wood surface is dull, the finish has no depth or luster. The surface is no harder than the raw wood and some of the woods, the cherry and the oak, have become quite rough as the finish hardened. Trident True Original Finish, the linseed oil and beeswax blend performed in much the same manner. The wood is warm and the grain is well defined. It also penetrated quite deeply, w That the surface is mostly flat with just a little bit of s I rubbed it with a microfiber cloth to see if I could get the beeswax to take a little s The finish is no harder than the wood itself and it feels a little waxy as you might expect. Now we're into drying oils. The Minwax Tung Oil Finish went on much easier than the previous two. It warmed the wood nicely and it built up a modest s It penetrated well, but nowhere near as deep as the pure Tung Oil or the linseed oil beeswax combo. The surface is moderately hard, although you can put a mark on it with your th You can see it developing depth with each coat and it sanded moderately well between coats, although the sandpaper loaded easily. When it's rubbed out, the finish has a very pleasant feel. The general finishes bowl finish was the t It warmed the wood color, but was a little anemic compared to the other oils in t It was very easy to apply and it built up to a nice s The bowl finish was reasonably easy to sand between coats, but you had to be careful sanding because the coats were so the surface is pretty hard and it has a nice feel after it's rubbed out. The Minwax Antique Oil warmed the wood very nicely and it built up quickly in coats to a deep luster. And it was modestly easy to sand between coats. It might have needed longer to cure between coats. The cured surface was very hard, but it had a pleasant feel when it was rubbed out. As I have said, the Minwax Wipe-On Poly was the only water-based coalescing finish in t And it was surprisingly user-friendly. It dried quickly and built up in t But it was wonderful to sand, very little loading on the sandpaper. If I was just looking for a finish that was easy to apply, t But it did not warm the wood very well. The color seemed washed out. It had a good feel in a decent luster, but little depth. Additional coats might have helped. If the Wipe-On Poly was the easiest to apply, the General Finishes Armor Seal was the most difficult. It built up in t It dried quickly, so quickly that it interfered with the wiping off process. It warmed the wood nicely, had a good feel, and I suspect that its extreme hardness offered better protection than all of the other finishes. But you really had to work for it. I want to emphasize that everyt I am HO, as I believe the internet prefix. It's as subjective as it gets, and it should be. I'm looking for something that I You could test the same seven finishes and get different results because you're looking for something that you And I urge you to do your own experimentation. You see how easy it is. It's not rocket science. It's just coding chemistry. And what about Rudy's original formula? It was dead as simple. Rudy He could build it up in several coats and then rub it out to any luster that the situation called for, flat, satin, or gloss. Rudy made t So, he applied the first two coats straight up, and then the second two coats, he added in a little spar varnish. One tablespoon of varnish to one cup of finish, or 15 milliliters to 235 milliliters. That's approximately a 1 to 16 ratio. T I've switched from a spar varnish to a spar urethane as the old varnish has disappeared from my local hardware store. But other than that, t It's versatile, attractive, easy to apply, feels good, and surprisingly durable. T It slides back and forth as you change the table angle. The finish is a little dirty, but it barely shows anywhere at all. So, would I swap Rudy's formula for any one of the finishes that I just tested? Well, probably not, but I am t I just have to do a few more experiments.