“I am building a bar top from 8/4 Walnut for my son’s new home, and he wants to have a very natural finish on it – no film finish allowed. My first thought was to use BLO, but some research has led me to think that Pure Tung Oil might provide better protection. Is Pure Tung Oil a better option than BLO for an open grained wood like Walnut?”

Tung Oil and BLO

When it comes to protection, boiled linseed oil (BLO) and pure tung oil are pretty similar. One important thing they have in common is that neither one offers a great deal of protection. If you have to choose between the two, I would say to go for the BLO since its cheaper. BLO does is said to “yellow” a little more over time when compared to tung oil, but that is a moot point with respect to walnut.

Now obviously your son is the boss here, right? But indulge me while I make a small suggestion. An pure oil finish will certainly be better than nothing at all, but for a bartop, your son might regret this decision after the first few spills. I can totally understand why he doesn’t want a film finish though. Personally, I hate the look of those super thick bartop finishes (epoxy). If someone wants that much protection, they should just put down a piece of glass or simply use something other than wood (can you smell the contempt? hehe). But keep in mind this isn’t an all or none proposition and you can achieve a compromise between the highly protective plastic look and the barely protected natural look.

The Oil/Varnish Compromise

So my suggestion would be to try to achieve the best of both worlds. Give the bar top a very natural-looking finish, while imparting a great deal more protection than what you would receive from an oil alone. There are a few products on the market today that contain oil and varnish together, like Watco Danish Oil. Because there is so much oil in the mix, you would have to put on about 4 or 5 coats before you really start to get an appreciable film. However, if you apply 2-3 coats, the wood will retain the natural look while protecting the surface with at least some varnish. If you go with a matte or satin formulas, I think your son will be even happier with the end result as it won’t have the eye-glaring reflective qualities of a typical gloss concoction.

One of the great advantages to using an oil/varnish blend is you can monitor the surface after each coat and simply stop when you have the look you want. Dilute the mix with mineral spirits if you want even more fine control. Also keep in mind that you can actually make your own oil/varnish blend by mixing 1/3 mineral spirits, 1/3 BLO (or tung oil), and 1/3 polyurethane.

Either way, make sure you sand lightly between coats to keep the finish nice and smooth. After the final coat, either sand with 1200 grit paper or buff with 0000 steel wool. The wood will not only look natural, but will easily repel the occasional spill.

Related Resources:

Oil Finish Basics (Video)
Make Your Own Oil/Varnish Blend

This Safety Week special article is brought to you by MicroJig!

This cautionary tale was was written by community member Tyler Reichelt.

I had a close call today.

I’m relatively new to the craft and have read up on safety as I’ve gone along. I’ve heard a lot of the horror stories about oily rags and such, but I haven’t used many oil finishes to date, so that topic wasn’t at the forefront of my thoughts just yet.

In any case, I am in the finishing stages of building a workbench and am testing out a few different finishes. One of the finishes I was experimenting with was boiled linseed oil. I hadn’t specifically read up on linseed oil, so I wasn’t very concerned with it. After all, it’s an oil derived from a plant. How dangerous could it be?!

Boy was I was wrong! I was experimenting with both linseed oil and tung oil and was testing different mixtures in little Dixie cups. The linseed oil cup was just about full and the tung oil cup was just about gone. I didn’t think anything of it and poured the tung oil into the linseed cup, stacked them, and promptly poured the mixture right into my dedicated sawdust trash can.

Even when I’m not working in the garage, I still frequently have the urge to go out into the garage and just be around my tools; maybe practice my hand-planing. Well, about an hour after pouring out the oil, I had one of these urges, so I went out. I immediately smelled something burning, but the smell was unfamiliar to me. I thought maybe one of my neighbors was burning something, but when I walked out into the driveway, the smell was gone. I walked back into the garage to try to find the source and when I looked in the sawdust can, I saw a small stream of smoke steadily rising from the sawdust; right where I poured the oil. I immediately ran inside and grabbed a big glass of water and poured it all over the spot. It reminded me of putting out a campfire. When you pour water on it, even though it may not look like much on the surface, when the water hits it, you know something hot is down there. The same applied to the sawdust. Upon digging around with a stick, I pulled out a charred blob about the size of a softball. It was down there smoldering for an hour!

If I had left it much longer or if I had used something bigger than a Dixie cup, the computer I’m typing this on might not have been here right now. I had no idea about the oxidizing properties of boiled linseed oil. Boy do I know it now!

As you can see in the picture(s), this was a disaster in the making. Oily paper towels and linseed oil poured right in the sawdust bin. Lesson learned!

A few weeks ago my woodworking shop caught fire and burned to the ground. Ironically, it appears that the boiled linseed oil may have been the culprit. Yes, I did in fact view and took heed of your safety podcasts and comments on boiled linseed oil. You did your best to warn me. The enclosed photos pretty much tell the whole story. Although I am struggling with the loss of my trusted tools and shop, the loss of my ?crown jewel” (my newest project) impacts me the most. Likewise, my wife (who actually had a vested interest in the vanity since it was the first time that she helped me apply the topcoat on a project), is really taking it hard. Not to mention that we now face the prospect of not having a functional master bathroom for the foreseeable future.

As I sit here this morning trying to assemble my thoughts and begin to fill out the insurance companies ?personal property inventory” my first entry is my Powermatic 66 table saw: my baby with less than two years in my shop. My Google search for the saw’s replacement cost takes to me to Amazon.com. I immediately think of the Wood Whisperer and hear your “The gold standard…” voiceover in my head. My brain (or what’s left of it after 30 years of spending my evenings and weekends in a woodworking shop) goes into hyper-speed as I envision a few interesting concept. First, I think that it would only be fair and appropriate that I go through your Amazon store for all my online purchases (especially since I’ve only been lurking on your site and haven’t yet joined or actively participated). Secondly, I start thinking what a unique opportunity I have to design a new shop from the ground up and include the Wood Whisperer community.

Fortunately, I have very good insurance and have no pressure to immediately rebuild my shop. Several woodworking friends have stepped up to meet my immediate needs and keep the wife off my back on the bathroom renovation. Consistent with my affliction to the woodworking bug, the clean-slate concept of starting a new project is rapidly breathing life back into my Craftsman spirit. What an emotional ride I have had these past few weeks! I’ve been rummaging through the debris pile trying to prod my memory of what I have collected these past 30 years and thinking about the possibilities of a clean slate.

Neither the Fire Marshall nor the insurance adjuster’s expert could conclusively determine the actual origin of ignition but all factors lead to the boiled linseed oil. The fire started at the rear door of my shop, nowhere near any electrical wire, outlet, equipment etc. There were only three things at the door (which was cracked open to help facilitate the evacuation of fumes from the prior day’s finishing operations); 1) all the partially used cans of oil-based stain, sealing (shellac/denatured alcohol) and BLO that were staged to be transported to my outside storage shed, 2) a heap of scrapped cut-offs destined to the fire pit and 3) approximately 50 paper rags saturated with the previously mentioned solutions. The spent towels (Scotts Rags in a Box) were scattered on the ground just outside the door earlier that morning to dry-out in an area that never receives direct sunlight (like I’ve done hundreds of times in the past, albeit this was the first time using BLO). Worst-case, the rags may have been laying four (4) or five (5) sheets deep. Even considering that some of them may have been folded once or twice over, I doubt that the paper towels were stacked thicker than 1/2″. Not the conditions conducive to generating sufficient heat that you would think necessary to start a fire.

My brother, who has a cabinet shop in Indiana, told me yesterday that he once experienced a similar unexplained incident several years ago. He replaced his spray booth filters and scattered the dirty filters out on the concrete floor in an attached garage/storage area to air-out since they were still wet. The next morning when he opened his shop doors, he noticed a particular smell and haze in the air. He traced the fumes down to the air filters, which were hot to the touch and actually producing some smoke! He claims that had he not found them when he did that they would likely have caught fire. For what its worth, he only shoots a small amount of oil-based stains and a lot of lacquer and related thinners.

Bottom-line: the jury is still out on what actually happened. Ironically, Ive been in the disaster recovery business for the past 24 years and am supposed to be THE expert on fires. My only out is that my specialty is actually what happens AFTER the fire, not what started it!

Related Links:
Hock Shellac Flakes
Charles Neil’s Shellac Video

As requested, here is a hi-res photo of the test boards: