Expert: Jamie Yocono - 10/18/2006

Question
Jamie:
I'm preparing to install faux hammerbeam trusses in my new home.  the truss elements will be 8X8 and 8X10 box beams constructed with Douglas fir.  Most real timberframes are finished with one coat of oil finish.  The project involves 800 linear feet of beams totaling about 1200 sq ft of exposed surface.  What I'd like to do is use a roller to apply the oil finish to the beams before they go up.  Roll it on, let it sit for X minutes and wipe it off.  I'm looking at the Watco danish oil material so I can darken the fir a bit in the process.  First, is the roll, wait, wipe process going to work for me? And second, how well do you think the Watco product will work on the fir beams?

Thanks

Steve

Answer
Hi Steve,

I use Watco Oil exclusively on my furniture, so I'll try to give some advice and information. There are many reasons I use this oil on furniture, primarily the great effect it has on grain and color, and second, the ease of application. So for those two reasons, using it on your beam would be beneficial.

However, you're applying it on a fairly large scale. And that could be problematic. Let me explain- when Watco is applied to raw wood, the first coat generally absorbs the oil like a sponge. There is usually no residue to wipe off. But generally, one coat of Watco is not enough. The wood will still look dry, like it needs protection.

The second and third coats that are applied start to build up on the surface, as the wood has now started to reach it's maximum absorption. The pores of the wood are beginning to be sealed off. It's critical that the next coats be wiped clean, before the oil can start to set up, or get sticky. On a big piece, like what you have, this could get hectic!

If you don't wipe off the excess, you'll end up with a sticky piece of wood, and it's quite labor intensive to eliminate the stickiness. An application of fresh oil will dissolve it, but it's going to take some time and effort, as the residue usually has to be scraped or sanded off.

On a beam the size of what you're working with, cleaning off any residue could be quite a job!

But I do have a couple of suggestions. First, I would definitely use Watco for the first coat, as it will bring out the color and character in your beam. I would recommend rolling it on, touching up any places that look dry with more oil. The idea is to saturate it pretty well for that first coat. Wipe off any shiny areas, where the oil has started to puddle up or accumulate. This is important.

By this time, your beam should be looking pretty attractive, with the grain and color brought out from the oil. But for the second coat, I would probably use some sort of polyurethane product, which will give you better results. I've used oil for paneled areas and beams, and they seem to be a magnet for dust and cobwebs. And certainly, as heat rises in your home, they start to look a little dried out.

As much as it pains me to say this, an application of a varnish will seal the wood better, and prevent it from absorbing too much ambient moisture from your home. See, you're going to need at least 2 coats of finish, regardless of what product you use. And the varnish will simply do a better job over time. I'm a big of a fan of Watco, but I certainly know it's limitations, and this might be one instance of that.

So my best suggestion would be to apply the first coat of oil, and then let it cure, for probably a week. Follow it with a coat of varnish, and you should have a beam that is both gorgeous and well-protected. Yes, you could apply 2 coats of oil, but my concerns are twofold. Watco needs a little maintenance over the years, and it's going to be a pain to do this once it's in place. And an oiled surface seems to attract dust. If you apply that 2nd coat of varnish, you should be set, and not have to do anything else for a long, long time. You can spray or brush the varnish, whatever you prefer.


OK, good luck, I hope this helps. Please feel free to write back if you have any further questions after reading this.  And if this answer was helpful... please take a minute and rate my service. Thanks!

Jamie Yocono
Wood It Is! Custom Cabinetry
Las Vegas, NV
www.wooditis.com