Staining or "smoking" oak

[Lasse Hilbrandt]

Im going to make a livingroom table for one of my colleagues. She wants it to be kind of brown walnut looking or the same color as "smoked" oak. I dont know the english word for it, but when you let the fumes from ammonium touch oak wood it becomes darker.

Im planning to use oak wood in two planks and Im planning to stain it, but I heard that staining oak sometimes creates something called blotching. How do I awoid that ?

[Stan Calow]

Lasse, we commonly refer to it as "fuming" so if you search on "fuming oak" you should turn up some threads. Its used mostly on white oak. I've done it a couple of times and it works but it is time consuming and working with ammonia is not pleasant. I know there are some alternatives techniques to get that same color, but I hope some experts will respond.

[Doug Hepler]

Lasse,

I have never fumed oak. The idea of fuming large pieces like a table top is daunting to say the least.

Blotching is a kind of random unevenness in color. It occurs when the grain is rising and falling toward the surface. The grain rising toward the surface presents open pores, which absorb more stain or dye than the grain that is parallel or falling. The pores that cause blotching are finer than the pores that you typically see in oak. Maple and cherry are notorious for blotching but in my experience oak is not. That is not to say that it can't happen in oak. One prevents blotching by filling the tiny pores with something colorless, either permanently or temporarily. My preferred method is to apply a washcoat of very dilute shellac or varnish to obstruct the pores.

Now, oak shows large pores. Some people like to see them. If you want a perfectly smooth finish, you can use a grain filler like Crystallac (I don't know what is available in Denmark). A grain filler is brushed on and wiped off. It fills the pores and also would remove any risk of blotching. Grain filler and washcoating definitely reduce stain penetration, so if you will want to darken the oak very much with stain or dye, you should apply it before grain filler.

I'm sorry if this sounds confusing, but grain filler and staining operate at cross-purposes. Anyway, that is the terminology you will need to search for further information.

Doug

[Prashun Patel]

I have never had an issue with blotching or uneven acceptance of stain on red or white oak.

[Wayne Lomman]

Lasse, I agree with Prashun - I have never had any issue with blotchy oak of any species whether European, American or Australian. If you are still concerned, use a pigment stain rather than a dye type stain as this will lessen any risk of blotching. Cheers

[Prashun Patel]

Wayne, while neither should be an issue on oak, I find pigment stains more prone to blotching than dyes.

Fuming is a process and requires safety considerations be taken.

It is also possible to use Sodium Nitrite to make both red oak and white oak antique.

The problem with chemical methods is that they are contingent upon the (usually) acid content in the wood, which can vary from lot to lot. The results can be unpredictable (IMHO always natural and nice looking; but still not controllable).

IMHO, you'd be better off following one of Jeff Jewitt's techniques. They involve layering multiple stains and dyes.

Even better still, I would first purchase a simple, close matching pigment stain, and show a sample on a test board, finished with your topcoat of choice, to your colleague. I almost always find that my customer's perception of the finish is more flexible and less critical than mine. So, you may save yourself considerable effort by keeping it simple.

[Lasse Hilbrandt]

Thankyou everybody. I will probably try to stain it, then apply oil, then a couple of coats of matt lacquer.

[Edwin Santos]

For the look you're after, you may like ebonizing the oak with a mixture of vinegar and steel wool (iron acetate). You can supplement this with a strong tea to increase the tannins. This can also be called an aged look.

Like someone pointed out, there can be variance from one board to another, but it's fun to do, inexpensive and you can adjust with the amount of tea or number of applications. I tend to like dark brown better than ebonizing all the way to black, but both look good. There's lots of information on the web about this process. It's a lot less demanding than fuming. Just another option.

[Rob Luter]

I’ve not found fuming to be that difficult, but a large piece like a living room table (coffee table?) could present a challenge. It’s fairly easy to approximate the look of fumed oak using dye and stain combinations. Here’s a small frame I did that used dye and stain to approximate a fumed look:



Here’s another example in a darker finish:



Additional arts and crafts finishes are shown on the Homestead Finishing home page, and a demonstration is shown here:

https://m.youtube.com/watch?feature=...;v=X9VbZxDBu-E

While it might seem complicated at first, it’s actually easy to get great results.