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Newsletter #156

#156 

 
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Greetings from Bill Boxer, Sr. Vice President, Apollo Sprayers International, Inc    

My simple tools that make a big difference and once you use them you can’t believe you ever lived without them!

January is a good time to review your tools and equipment and organize and reorganize so you know exactly where everything is.
Last week I was in my shop spraying a rocking chair for my new grandson’s nursery. I reached for my blow off tool and much to my annoyance it was not there. I could have blown off the dust with the end of my HVLP hose, but I wanted that exact tool and it wasn’t there where it always was and where I expected it to be. I went into my search mode, angry, stomping around, and assuming someone had sneaked into my shop and removed it for some unknown purpose. When I finally found it, under an open book, I realized that there were certain small, inexpensive tools on which I have come to rely. I call there my simple items that make a big difference and once you use them you can’t believe you ever lived without them.
These include my Blow Off Tool, Wet Mil Gauge, Filter Stand, Kleen Again, Zip Sander, Painter’s Pyramid 

 

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                                                                Painter’s Pyramid in Action

Finishing Feature Article: 

Enhance the Appearance of Wood With Stains                                                                     
by Carl Duguay 

While there are some woodworkers who might cringe at the thought of staining wood, there are good reasons why you might want to do so. Some lighter colored woods, such as poplar, alder, beech, and birch do tend to look somewhat bland, and can benefit from a dash of color. Who hasn’t bought a load of wood, only to find, after milling, a disappointing variation in the color – staining can even out the tone of the wood. When building new furniture or cabinetry to match existing pieces, staining might be the only way to blend the two. And, with the price of some exotic woods, such as ebony, reaching stratospheric levels, staining a wood to mimic the look of another species might not seem like such a bad idea. Or, you might simply want to make a really bold design statement. Whatever the reason, enhancing, and even completely altering, the color of wood is a valid, and indeed time honored woodworking tradition. 

In a nutshell, a stain is a colorant that’s dissolved in some kind of solvent (aka ‘carrier’). The two most common types of colorants are pigments (which cover the wood), and dyes (which penetrate the wood). Some manufacturers combine both pigments and dyes into a single blended stain. The solvent can be alcohol, a petroleum distillate (such as mineral spirits, kerosene, and naphtha), and even the actual finish. A binder is added to pigment stains to help the colorant attach itself to the wood – typically the binder is a resin (acrylic, vinyl, alkyd and the like).

Bombe Box by Charles Neil

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Pigment Stains

Pigments are fine insoluble particles of inert chemical compounds that can be natural (like iron oxides) or synthetic. Because pigment particles are heavier than the binder, they settle to the bottom of a can – which is why you have to stir these stains before using them. That big glob at the bottom of the can is a sure indicator that the can contains a pigment stain.  

Pigment particles lodge in the pores and scratches on a wood surface, exaggerating grain differences. A pigment stain on open porous woods like oak tends to color the early wood more darkly than the denser latewood. However, on closer grained wood like maple, the stain would be much less pronounced because those pores are so small.  

Dyes

While pigments remain closer to the surface of the wood, dyes are absorbed into the fibrous structure of wood, which means the wood will be much more evenly colored. Dyes can be either natural or synthetic. Like pigments they require a solvent, but they don’t use a binder. This is because dye particles, which are about 1/1000th the size of pigment particles, are fully dissolved in the solvent, while pigment particles are suspended in the solvent. Because dye particles are dispersed uniformly throughout the stain they don’t have to be stirred. Like pigments, dyes can be dissolved in water, alcohol, petroleum distillates like naphtha, and in glycol ethers – in which case they’re generally referred to as non-grain raising (NGR) dyes. 

While natural dyes are prone to fading, modern synthetic dyes are quite fade resistant (when used indoors). The nice thing about dyes is that you can apply one color directly on top another color. You can purchase dyes either as powders that you dissolve in a solvent (water, alcohol, oil) or pre-mixed in a solvent. 

Chemical Stains
Sometimes you’ll read about people using various chemicals to color wood – potassium dichromate, ammonium hydroxide, sodium hydroxide, along with a range of other suspicious sounding names. Most of these chemicals are both poisonous and caustic, so you should really avoid them. There are so many stain colors available today that you’ll certainly find the right one for your project without compromising your health. 

Staining Tips                                                                                                                                                                                     
Staining wood isn’t difficult, just a bit messy sometimes. You can apply most stains with a brush or rag. It’s important to note that different woods take stain differently. In fact, even one species of wood will take a stain differently depending on such factors as how the board was cut, the wood grain, and the relative density of the wood. Woods like pine, poplar, alder, and birch are notorious for blotching. For blotch prone wood I apply a thinned coat of shellac before I apply the stain. I also apply shellac on the end grain, which has a tendency to absorb stain like a sponge and darken much more than the surface. 

Proper sanding of both solid wood and plywood is a key to achieving optimal results when staining. Make sure that you do a final sanding by hand, in the direction of the grain. Shine a light across the surface of the wood at a 45º angle – it will help you see any imperfections that need attending to. Also sanding the end grain smoother burnishes the pores and reduces their ability to absorb stain. It’s important to remove excess glue completely, particularly around joints. 

It’s a good idea to do a trial run on scrap pieces before you begin staining your project. You can experiment by diluting the stain with its solvent (check the label on the can) or laying on two or three coats of stain (allowing each coat to dry in between, of course). You really want to stir the contents of the can thoroughly before applying the stain. It’s important that all the pigment is dispersed in the liquid as opposed to sitting on the bottom of the can. Generally, if a wood is very hard and dense, you should sand to a coarser grit than if the wood is soft and porous. If you sand maple to 220 grit it will absorb very little stain; better to sand the maple to 150 grit. However with oak I tend to sand to a higher grit, often 320. 

For important projects I always buy ‘architectural’ or ‘cabinet’ grade plywood. Typically the face veneer on the good side will be one continuous sheet. Building supply stores typically carry a lower grade of plywood. Often, the face veneer is made up of multiple parallel bands of veneer joined together and running the length of the sheet. aquatone-52355.1410656989.220.220.jpgThe bands may not be matched, and more often than not there are even gaps along the glue lines. When stain is applied, the glue lines will likely absorb stain differently than the veneer. 

Ban the Blotches
Some woods, such as pine, cherry, and birch, are blotch prone – they absorb stain unevenly. For these I use a gel stain. These thicker stains don’t penetrate wood grain as much as thinner liquid (oil or water based) stains. A second option is to apply a wood conditioner (aka washcoat) before staining. The wood conditioner will help the wood absorb the stain more evenly. You can buy an off-the-shelf conditioner, or make your own by diluting your finish with the appropriate solvent in a ratio of 9 parts solvent to 1 part finish. Remember to allow the conditioner to thoroughly dry before applying the stain. 

 

Lay it On
You can apply stains with a paint brush, foam brush, by rag (my preferred method), or spray. Liquid stains, particularly water based stains, dry fairly quickly, so on large surfaces you want to maintain a wet edge, to avoid lap marks. sawhorse-thumb.jpgIf they do occur lay on a second coat of stain after the first one has dried. On any project that will likely be exposed to direct sunlight, use a pigment stain – it’s much more lightfast. For projects that require vibrant, bright colors, or where you need to match an existing stain as closely as possible, use dyes. Any stain will result in a darker color if you leave it on longer, or if you re-apply it after the initial stain coat has dried. 

Don’t take my word for it – you really need to try several different stains to find the one that suits your needs. Most are available in half-pint sizes for a few dollars a can. Once you’ve latched onto a stain that you like, experiment with it on the woods that you typically build with. Try different finishes on top of the stain as well. 

You wouldn’t expect to cut perfect dovetails the first time you try, so you shouldn’t expect to get perfect staining results without some practice. But you will be surprised just how easy it is once you’ve invested a little time in honing your staining skills. 

Finishing Tip by Bob Flexner: If Stain Gets Wood Too Dark 

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If a dye stain gets the wood too dark, try removing some of the dye by wiping with its solvent. The powder dyes labeled Lockwood and Moser (which are the same) are easier to lighten than the liquid dyes labeled “NGR” (non-grain-raising) or Transtint (which are also the same; Transtint is just concentrated).

If a pigment or wiping stain (those that contain a varnish, lacquer or water-based binder) gets the wood too dark, try removing some of the color by wiping with the thinner for the stain or with lacquer thinner or acetone. These stains are much more difficult to lighten than dye stains.

In both cases, you can also scrub the surface with steel wool or a synthetic abrasive pad together with the solvent or thinner for the stain to remove more color. Try to keep the scrubbing even over the surface so you maintain a roughly even color overall.

With dye stains, you can usually bleach out most of the color using household bleach or swimming-pool bleach. It won’t be possible to remove all the color, however, without many applications, sanding between each.  

 

Finishing Tip by Bob Flexner: “Equalizing” Sapwood

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To achieve an even coloring with darker colored woods, it’s always best to use only heartwood to begin with. But this isn’t always possible. So you may want to “equalize” the coloring of the sapwood and heartwood.

But it’s usually better to equalize the sapwood to the color of the heartwood.One method is to bleach the wood using two-part bleach (sodium hydroxide and hydrogen peroxide). This will remove the coloring from the heartwood, so you can then stain the wood back to the color you want.

The easier way to do this, if you intend to stain the wood dark, is to use a dark dye stain as shownin theaccompanying picture. Light colored dye stains don’t work as well,manned stains that contain binders, such as oil, water-based and lacquer stains, work even less well. 

 

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Though more difficult, the best way to equalize the coloring is to spray a dye stain just on the sapwood, asshown on the middle stripe in the second accompanying picture. You can then follow with a binder stain if you want to further equalize the coloring, as shown on the stripe second from the right. Finally, apply the finish, which will produce the true coloring.