Posted on May 7th, 2013 No comments
If you want to make the tabletops on your stationary machinery (table saw, band saw, jointer, etc.) slicker so boards slide easier, use paste wax, not furniture polish. And choose a paste wax sold for furniture or floors rather than for cars.
The reasons for both instructions are the same. Many furniture polishes and paste waxes for cars contain silicone, which could transfer to the wood and cause finishing problems—specifically fish eye (cratering).
Furniture or floor paste waxes shouldn’t cause any finishing problems as long as you buff them out well on the tabletops.
One of the things that I enjoy is experimenting with finishing. One of my favorite things is the antique looking finishes. While I do a lot of formal finishing, particularly on period pieces, I do enjoy playing with the old aged look and I must say they have served me well. Over the years we have sold a lot of what we call “primitive” pieces, where the objective has been to make them look old. The same techniques are used in antique restoration as well. If we had a repair to make or needed
to replace a part we had to get it to match. If it was a formal piece that had a nice stained or naturally aged , we could usually achieve the color with a little experimenting with various stains and dyes. When it came to the more “rustic pieces” we had to get a little more creative and this is what I find to be a lot of fun.
Even to this day, one of my favorite “aged finishes” is the all too familiar “crackle” finish that is done to mimic old aged, cracked paint. While I was willing to let go of the bell-bottom pants and tie dyed shirts, I still held on to the “old crackle” finish. I must admit that I prefer to take it a bit further than most and clients like the look. It’s pretty easy and forgiving to do.
Here is a Shaker Herb Cupboard made from inexpensive white pine, I hand planed all the surfaces to give it a slightly “hewn look”, wasn’t trying to get a perfect surface, actually the opposite. I wanted a little tear out and “flavor.” Then a 10-minute quick buzz sand with some 220 grit sandpaper just to ease the edges and remove any plane shavings. Next, I hand planed the edges and the ends of top to “droop” them. I didn’t want a perfect edge, but rather a worn well-used one. Simply sealed it with a coat of water base finish and then a quick scuff sand with some 320 grit sandpaper just to remove the fuzz. I then sprayed it with a coat of black latex paint from the box store. When dry, I brushed a coat of hide glue (brown bottle premixed) thinned about 10% with water and let it dry until it felt hard, (about 2 hours) then I shot it with a medium dark red latex. and using a heat gun dried it as fast as I could. The faster it dries the better it cracks, also, the heavier the paint the larger the cracks. I shot it both times with my Apollo Atomizer gun with a 2.0 needle/nozzle. I thinned the paint about 5% and it was excellent. You can brush the paint, however, often you will find if you brush too much the paint will have softened the glue and it can get messy.
The next step was to have my daughter add some flowers, and a little decoration, Then I sprayed it
again with some water base finish to seal everything down. When dry, I gave it a good scuff sand with 320 grit sandpaper and using a dark blue paint I sort of glazed it a little. I used a wet cloth and the blue paint to leave “tinges of blue” here and there, and let it hang in some of the cracking. Then after that had dried, using a dark walnut water base stain, I glazed it again, this gave it the old aged look, making it “dirty” if you will. The glazing also “muted” the yellow in the flowers and gave them an aged look as well (insert photo 6688).
Next step was to apply 2 more coats of water base finish, let it dry well, then a
quick scuff with some 320 grit sandpaper until it feels smooth and then a coat of wax. Has very little to no sheen and feels great and will hold up well.
While many will sand the corners and wear off areas, on this one we elected not to, and the recipient (my daughter), was calling the shots and didn’t want the worn look, it still works well and looks good.
I realize this is not everyone’s cup of tea, but they sure make a statement and we have then in multimillion dollar homes, right alongside expensive formal pieces, and they sure look good. This also makes for some fun family projects, and remember you just can’t do it wrong. So have some fun, (by the way the ladies really like paint, because it can always be changed. I will not elaborate on that).
You can also use just a plain Elmer’s glue for cracking, there is several articles on the internet about it, it works a little differently than the hide glue and is cheaper, with it you want to paint over just as the glue becomes tacky, and it does well, and is less messy than the hide, however not all latex paints crack as well as others, so if your choice doesn’t crack with the white glue, try the hide, and as always experiment with scrap and get a feel for what you’re doing, be sure you have your technique figured out, Now, go have some fun and if ya don’t have a little mess, you didn’t do it right.
Matching colors is one of the most difficult tasks in wood finishing. Using just a stain rarely works well because the color on the object you’re trying to match is affected by how the wood and finish have aged. The best way to match a color is usually to get the color close, but a little lighter, with a stain, then spray a toner.
A toner is pigment or dye added to a finish and thinned a lot with the proper solvent. Then it is sprayed.
But how do you know what color to make the toner? Here’s the trick. Spray some of the toner you think is right onto a clean glass plate and place it on the wood you’re trying to match.
You’ll know right away how you need to tweak the color to get a match.
Ghosting occurs when you sand or rub through one layer of finish into the one below, as shown in the accompanying picture. You can recognize ghosting when the problem area you’re trying to remove keeps getting bigger rather than smaller—like sanding through veneer.
The term ghosting is the traditional name for this phenomenon. As it starts to appear, you see the “ghost” of the finish layer underneath. It is also called “layering,” which describes the phenomenon well, and “witness lines,” a relatively new term, which doesn’t. Nevertheless, it seems that witness lines has become the favored term in many recent wood-finishing articles and books.
Ghosting doesn’t occur with shellac and lacquer finishes because each coat dissolves into the previous one so that all coats become one. Dissolving doesn’t happen with varnishes, including polyurethane varnish, or with most water-based and catalyzed finishes. The separate coats form separate layers that are vulnerable to ghosting.
Sometimes you can disguise ghosting by rubbing with an abrasive such as steel wool. The problem is still there, but the scratches hide it.
The better solution is to apply another coat of finish after you have removed all the problems that caused you to sand deep in the first place. Then level and rub out this new coat without going through it.
Posted on March 4th, 2013 No comments
It’s common to hear woodworkers lament that they don’t like finishing because they are afraid of ruining their woodworking project. So the following is an important point to keep in mind:
The only thing you can do in finishing that can’t be fixed fairly easily is to blotch the wood with a stain or decide after you have applied a stain that you don’t want it. All other problems can be fixed, with the worst case being that you have to strip off the finish and begin again. Nothing is ruined.
Blotching, like that in the accompanying picture, occurs on softwoods such as pine, and tight-grained hardwoods such as cherry, birch and maple. It’s difficult-to-impossible to totally avoid blotching on these woods if you use a stain.
So, depending on the wood you use, it’s really the stain you have to be concerned about, not the finish. You can’t “ruin” anything with a finish. Choose your wood and whether or not to stain with this in mind.
Posted on March 4th, 2013 No comments
There are two ways to get a satin (matte) finish—that is, a finish with less shine and reflection than gloss: rub the finish with abrasives or use a finish that contains flatting agents. There are pros and cons to each.
The easier of the two, by far, is to use a finish that contains flatting agents, usually labeled satin, matte, flat or semi-gloss. The terms are vague approximations of sheen (amount of shine or gloss) you will get. Some manufacturers selling into the professional trade use a numbering system to indicate sheen, with 90 being gloss and 10 being very flat.
Rubbing with abrasives is much more time consuming because you have to sand and abrade through a number of grits. Usually, you begin with fine-grit sandpaper, then advance through several abrasive powders, such as pumice and rottenstone, or rubbing compounds.
Rubbing produces a much more perfect finish, with no flaws if you do it well, and with a much more pleasing soft, silky feel. This is good, and the extra work is often worth it for tabletops. But rubbing, by definition, leaves fine scratches in the finish. (It’s the scratches that create the lower sheen by reflecting light randomly.) And the scratches show marks easily when objects are moved on the surface. Even lightly dragging the back of your fingernail perpendicular to the polishing scratches will leave a mark.
So rubbing can produce a much more perfect finish than using a finish containing flatting agents, but rubbing also creates a fragile finish. To reduce the likelihood of scratches showing, apply a paste wax or a furniture polish that contains silicone to the surface. Most aerosol furniture polishes, with the exception of Endust, contain silicone. They are very effective at reducing scratching and they usually make the wood and finish look deeper and richer.
There are a number of considerations when choosing the type of finish you want to use. These include durability, ease of clean-up, odor, etc. But one consideration doesn’t seem to be fully appreciated, and that is the color the finish imparts to the wood.
Most finishes give wood a yellow/orange tint. Until water-based finishes became available a couple of decades ago, color was never much of an issue because all finishes added this tint. But now you have a choice because water-based finishes (all finishes that thin and clean-up with water) don’t add any color at all. They just make the wood a little darker.
The accompanying picture shows water-based finish on a pine floor. The pine will darken some as it ages, but for a number of years the water-based finish will give the floor a unique and attractive look. This same look can be achieved with all white woods such as maple and birch. And these woods won’t darken.
Say you stain an object with a store-bought oil (“wiping”) stain and the color is too dark. Assuming you haven’t yet applied a finish, how do you lighten it?
Most importantly, don’t sand. Whatever you do, you have to do the same everywhere to keep the color even, and you won’t be able to control the depth you sand to evenly.
It’s much better to try wiping with naphtha. It’s a little stronger than mineral spirits. See if it pulls out some of the color. What you’re trying to do is break down enough of the binder that holds the pigment particles together and to the wood to lift some of the color.
If this doesn’t work, try acetone or lacquer thinner. If this doesn’t work, try paint stripper—any kind. This will be messier, which is why I’m suggesting it last. You ought to be able to remove enough of the color with one of these solvents.
But if you’re still unsuccessful, you could try rubbing with steel wool. It will be easier to rub evenly with steel wood than with sandpaper. You could also try using the steel wool together with one of the solvents to see if that helps. The most important thing is to try to keep the remaining color even.
Many tropical woods, with the notable exception of mahogany, contain an oily resin that causes oil and varnish finishes to not dry well. The oily resin gets into the finish and keeps the finish molecules from hitting each other and crosslinking. The resin acts like paint thinner that doesn’t evaporate.
Counter-intuitively, the oily resin usually doesn’t affect the drying of lacquers and water-based finishes. But in cases where the oiliness is severe, it could weaken the bond to the wood.
The trick to finishing oily woods successfully is to remove the oil from the surface just before applying the finish. Don’t wait a long time before finishing or the oil that is deeper in the wood will rise back to the surface. It’s best to remove the oil with naphtha because it evaporates rapidly. You can also use acetone, but if there are several woods involved, as in the accompanying picture, acetone is much more likely to lift some of the color from the darker wood and transfer it to the lighter wood.
Many years ago, back when the dinosaurs roamed the earth, I had the privilege of working with two older gentleman in Charleston, South Carolina. Their forte was antique restoration as well as creating reproductions of the same. They went by the names of Jim and Bob, one was from Germany as I think, and the other from Sweden or Italy, I can’t recall. The language barrier for whatever reason was not an issue, even though neither spoke very good English. It was simply woodworking seem to create a universal understanding between us. As close as I could determine they were in their early 70s when I met them. They had a very low-key, hidden little shop and the only thing electric was the incandescent light bulbs in the ceiling. Everything was old-school, lots of hand saws, old wooden bodied hand planes, molding planes. For me this was a dream come true, I was young and anxious to learn, I had my regular day job if you will, but I spent as much time as possible with them. I never got paid and in reality I thought I should be paying them. It is a time in my life I reflect on daily.
One of the things I quickly picked up on was their “concoction” that they seem to use on everything, it was used to stain, glaze and and worked quite well. The concoction was quite simply “Roofing Tar,”thinned with mineral spirits or naphtha. Depending upon the ratio of the tar to the thinner you could make about any shade of brown you wanted. I later learned it was actually the base for almost all oil base brown stains. They simply used, typically, linseed oil and the tar.
Over the years I kind of almost forgot about it, although I used it many many times. Several years ago I was reading a book by Michael Dresner, and he mentioned it. It brought back a lot of fond memories. However, somewhere through the years water base and alcohol dyes dominated in my work, and so the “concoction” lay dormant in my brain. A couple of weeks ago I was looking through the magazine that the Society of American Period Furniture Makers puts out. A gentleman had an article about using the Asphaltum for a glaze, and again the lightbulb went off. So to refresh my memory and have a little fun, I got some foundation coating without the fiber and started experimenting, suddenly my brain was filled with fond memories and superb results coloring wood.
As I stated, by varying the ratio you can create pretty much any color you want. In the photos you will note some samples, we were able to match, for example, Min wax Golden Oak, Provincial, Early American and so forth.
You will note that on the extremely sappy Walnut by applying a heavier concentration on the sapwood and allowing it to soak a bit then using a thinner mix over the entire thing we were able to blend the sapwood as well as give the Walnut a nice golden brown antique look. As most are aware Walnut lightens as it ages, not to mention most Walnut today is steamed in the drying process. This steaming causes the tannins in the wood to leach into the sapwood and color it. The purpose of this has to do with the fact that sapwood in Walnut is considered a defect. Steaming allows the lumber mills to have a better yield. Unfortunately, one of the other things it does to the Walnut is to make it darker, and in my personal opinion not in a pleasant way. When finished it seems to have a purplish tone to it, I am not a fan. By using a thin mix of Asphaltum which has the brown/gold tone to it we are able to overcome the purplish tint and have a nice color. One of the other advantages is that it will blend varying shades together to give a more uniform look. Works wonderfully.
Here’s a photograph of it used on quarter sawn White Oak, you will note that the bottom is obviously darker, the color above the darker section mimics Golden Oak. This is a perfect example of how you can alter the color to your liking by virtue of the ratio of the tar (a.k.a. asphalt) and the mineral spirits or naphtha.
Here’s some cherry that again by altering the ratio we can get whatever tone we want.
Here’s a strip of mahogany again varying the ratio it allows us to remain in full control of the color.
Here is one with a little twist, we used some General Finishes Cinnamon Dye as a base color then the Asphaltum over it, this allowed us to create the deep rich burgundy color that is very desirable for mahogany. In reality you could use the same technique on about any wood, it is especially nice on cherry as well. Not to mention you can color Poplar, pine or basically any secondary wood to match.
Try applying a heavier coat then a thinner coat over some poplar, exactly as we did on the Walnut sap wood, you will be amazed at how well it mimics Walnut.
To cut to the chase, by experimenting a little you will be amazed at the various things you can do. You can add it to your favorite oil and create your own “Danish Oil”. It also works excellently as a glaze, especially with carvings. You need to remember that a glaze is used over a finish, meaning once you have a coat of finish then you can apply the Asphaltum and using some mineral spirits or naphtha wipe off the excess leaving whatever you desire in the carving or all the nooks and crannies if looking for an antique look. In the event you get a color too dark again using some mineral spirits or naphtha you can remove the color until you get what you want.
One of the things you’re going to notice since we are using mineral spirits or naphtha is that it will dry back very dull, unlike a commercial stain where the oil is used, and will impart a sheen. The mineral spirits or naphtha allow it to act more like a dye than a stain, in my opinion that’s a really good thing, it also dries pretty quick, so if you plan to wipe it back to lighten the color do it as soon as possible.
One other thing when dealing with the tar, the foundation coating is thinner than the roof patch, but even then it’s like thick molasses, trying to pour it out of the can can be quite messy, simply dipping a stick in it or using a small dipper is the best way. You also want to keep notes and measure accurately so as to be able to match the colors in the future.
Irrespective of whatever topcoat you plan to use, be sure to allow the stain to dry well, if using a wipe-on oil, go easy so as to not disturb the color, after one or two coats of oil it will all be locked in. If you want to use a water-base topcoat I suggest a coat of shellac over the Asphaltum after it has dried just to be safe.
In conclusion, if you experiment a little you will be amazed at all the various things you can do, and by the way did I mention is extremely cheap compared to commercial stains?
As many of you may know, I’m finishing up writing a book on finishing and Asphaltum definitely has a chapter, it’s just one of those forgotten gems.