Michael Dresdner » stain

A shade more glycerin

Michael — Thu, 12 Aug 2010 14:00:01 +0000

Q: I just obtained two small table lamps made of burl and the lampshades are of what appears to be birdseye maple veneer. The veneer is fabric backed and very brittle. As a result there are some small voids and cracks in each shade. I plan to back the voids with wood putty and then use a wood stain. This won’t entirely correct the problem but do you have any suggestions for application? Moreover will glycerin help to restore some of the suppleness and help avoid future cracks?
A: Glycerin may help restore some suppleness, and may even help slow the cracking, but once you put it on, you really can’t do anything else. In other words, glycerin will prevent the stain you plan on using from taking evenly, and stain will prevent the glycerin from being absorbed. You may have to choose one or the other.
To be honest, I don’t understand why you want to stain the shade veneers, but if you do, you’ll have to clean and sand them first. Most household goods develop of thin coating of airborne oils, and while they look clean, are not. Raw wood will simply absorb such oils. Either way, trying to stain other than raw, clean, sanded wood can result in problems.
For what it is worth, the cracking is almost certainly a function of the heat and attendant dryness coming from the bulb behind the lamp shade. Replacing the bulbs with cool to the touch compact fluorescent bulbs will help eliminate much of the heat and may prolong the life of the shade.

Fume a beam?

Michael — Tue, 10 Aug 2010 14:00:41 +0000

Q: I want to fume the ridge beam in my house. Obviously, I can’t simply remove it, and place it in a tent for fuming. What would happen if I painted a light layer of ammonia on it?
A: First, fuming only works with woods high in tannin, so before you do anything, figure out what type of wood it is and whether it is one that is high in tannin or not. Second, fuming uses ammonia fumes, which is pure, concentrated ammonia. Once it is in liquid form it is ammonium hydroxide, which will color wood, but not in the same way as fuming. It tends to be less effective and yields a different color which is not surprising when you remember that you are no longer using pure ammonia, which is a gas, but rather a compound of ammonia and water. Even at best, fuming is a bit of a crap shoot. What color you get and how much impact the ammonia will have depends on the type of wood and, in this case, the concentration of ammonium hydroxide. For example, household cleaning ammonia is usually only about a 5% solution, and is a weak chemical stain at best. Ammonia from a blueprint machine is typically a 26% solution, and while more effective, is both dangerous and noisome to use. Finally, chemical stains, which is what ammonia is, only work on clean, raw, sanded wood. Call me a skeptic but I doubt that’s a good description of any ridge beam unless it is brand new and recently sanded. In short, I think it is a very bad idea for a wealth of reasons. Why not simply stain it the color you want it to be?

Mixing vs. buying stain

Michael — Mon, 09 Aug 2010 14:00:30 +0000

Q: When you say to control the color by how you mix the stain not how you apply I am a little confused. My stain is premixed. It is General Finishes water based dye stain. Can that be thinned using water and do I need to thin it?
A: You can thin any stain, should you need to, but most pre-mixed stains are designed to be used as is from the can, which means you can make it weaker but not stronger. That’s one reason most finishers prefer dye concentrates or powders, which allow them more flexibility in stain control. Such raw ingredients also allow you to omit or add binder as you choose. Pre-mixed stains offer convenience, but the price of that convenience is reduced versatility.

Just a shmear

Michael — Fri, 06 Aug 2010 14:00:59 +0000

Q: If I brush on a final finish, will it cause water based dye stain to bleed into the finish on the brush and smear?
A: Water soluble dye can bleed onto a brush loaded with waterbased finish. Whether that will be enough to smear the stain also depends on your brushing technique and how aggressively you wiped the dye originally. It is also worth noting that some dye stains contain a binder that will prevent this. Others don’t.

Odds of even

Michael — Tue, 27 Jul 2010 19:49:19 +0000

Q: I built a small table from reclaimed mahogany. There is a lot of variance in the colour and grain pattern. I want to stain this so to even out the colour. What do you recommend?
A: Most pigmented stains work very well on mahogany to even coloration, in large part because they take full advantage of the large pores. In extreme cases, we usually use a two stage approach to making wildly varying woods look one color; we start by making the background uniform with a dye stain, usually in a color in between the darkest and lightest values to bring the two together. Once the dye is dry, we follow up with a pigmented stain to add unifying color atop the dye and in the pores. It works surprisingly well.

India ink for ebony

Michael — Tue, 06 Jul 2010 14:00:46 +0000

Q: I’m planning to ebonize a project using India ink. Is there anything I should know before I tackle this, such as warnings about curing times or lap marks?
A: Use waterbased India ink as opposed to oil based, and treat it as you would any stain; flood it on liberally, then wipe it all off while it is still wet, leaving only what the wood was able to absorb. That flood on, wipe off method will eliminate lap marks. Like all waterbased materials, drying times depend on humidity, so drying can be from a few minutes to many hours. Fortunately, the wood will look and feel different dry than it does wet, so you should have no problem on that score. And as always, try this and any new finishing method on scrap first.

Matching Martin

Michael — Tue, 08 Jun 2010 14:00:05 +0000

Q: I’m restoring a Martin guitar, and after staining, I added three very
light wash coats of 1lb. cut shellac. I’d like to strike the pores black
with Finishers Glaze seal with sanding sealer, fill pores with Bartley’s dark, seal and topcoat. Martin mahogany pores are darkened nicely. I’m trying to do it the right way.
A: I’m afraid you are doing it the hard way. The easy way is to stain the wood, preferably with water soluble dye, seal with one thin coat of SealCoat or dewaxed shellac, then fill the pores with a dark pore filler. There is no glaze on Martin guitars, and many were stained and filled in one step, on the raw wood, with staining pore filler. Keep it simple and you will have better results.

Purple heartbreak

Michael — Fri, 14 May 2010 14:00:19 +0000

Q: I made a small box out of Purple Heart. What can I finish it with to get a brilliant purple color?
A: Purple stain or dye. I realize that sounds like a strange answer, but it will make more sense if you bear with me a bit and let me explain a few things about purpleheart.
When you first cut or sand purpleheart, it turns a sort of grayish, ashy color. Let it sit in the presence of oxygen (air) and in a couple of days it once again deepens to its nice, rich purple color. For that reason, it is the only wood we generally do not finish immediately after sanding, Letting it sit two days will give you more rich color.
That’s the good news. The bad is that any finish that is amber, such as an oil, most lacquers, shellac or oil varnish, will discolor the purple, since yellow and purple make brown. Thus, it’s good to avoid amber finishes. Worse, once exposed to light, the wood will soon fade to brown, even after it is finished. Keeping the piece in the dark will help, but then, we can’t much enjoy it in the dark. That’s why many people resort to staining the wood purple, especially with lightfast pigments or largely lightfast dyes. By adding stain that matches the original color of the wood before finishing, you can keep the same color and also preserve that color longer after finishing.

Where to look it up

Michael — Wed, 12 May 2010 14:00:00 +0000

Q: Are there any of your books or DVDs that I can buy that would help me solve problems I am having with staining projects?
A: All four of my books and my DVD cover various aspects of staining, both in how to apply stains evenly and how to correct for uneven staining. The best combination, in my opinion, is The New Wood Finishing Book, which is a basic textbook on finishing, paired with Wood Finishing Fixes, which is a Q&A format troubleshooting book. Both are available on my books and videos page.

Plywood vs. solid

Michael — Tue, 11 May 2010 14:00:15 +0000

Q: When I try to stain a project like a bookcase that has both red oak plywood and solid red oak, the colors of the two parts come out drastically different.
A: There are several steps that will help you deal with this, and you may need just one or many. First, sand both the plywood and the solid wood through the same sanding sequence. It’s tempting not to sand plywood as it is already smooth, but unlike solid wood, veneer is cut with a knife that compresses the surface fibers. The opposite is true of solid wood. Normally you would start sanding solid wood with 80 or 100 grit paper and go up through the grits to 180 or 220. Do the same sequence on the plywood, even though it means going backwards on the coarsest grits, and the woods will behave more similarly when absorbing stain.
That will work on many panels, but some types of plywood have veneers that have been impregnated by the adhesive, and are more resistant to absorbing stain, even when sanded properly. If you are using a pigmented stain, you can restain those areas the second day, wiping a bit less aggressively so as to leave them darker. Otherwise, use a tinted topcoat, a technique that is also used to even up dyes. You can’t use your stain, but you can add compatible dye or a bit of concentrated pigment in a compatible medium, such as artists colors, to the top coat to make a tinted toner. Spray or brush it selectively onto the lighter areas to make them even.