After researching and testing a number of stains and sealers for butcher block countertops, we decided to “stain” our counters using a simple iron acetate solution made from vinegar and steel wool. If you know my fondness for a good chemistry project, you’ll understand how excited I was, when I discovered this method. Note, this post specifically covers the staining process and not the cutting or measuring portions on installing butcher block counters. There are already many great resources online covering those topics. For those interested, we used butcher block slabs purchased at Menards and cut them with a combination of circular and jig saws.
Total – $21
- Steel Wool, Super Fine Grade #0000 – $2
- 1 Quart Distilled White Vinegar, 5% Acidity – $2
- Howard Butcher Block Conditioner – $9
- 220 grit Sanding block – $4
- 320 Grit sanding block – $4
How it Works
The science behind this project is fairly simple. When acetic acid (i.e. household vinegar) and iron (from the steel wool) combine, the result is an iron acetate solution. When iron acetate (sometimes called ferrous acetate) is applied to wood, it reacts with the natural tannins in the wood, producing a darker color which varies from shades of brown or gray to deep black. Depending on the level of tannins in the wood, the resulting color will be lighter or darker, with more tannins resulting in a darker color. Typically darker woods like oak, walnut, and mahogany have higher tannin content, while lighter woods like pine, maple, and birch have lower tannin content. This technique is often called “wood pickling” or “ebonizing”. It’s not a stain in the traditional sense because you aren’t applying pigment to the wood but rather oxidizing compounds already present in the wood to create a darker color.
We purchased butcher block slabs made from birch, which has relatively low tannin content. Since we didn’t want really dark counters, but instead a medium brown, the limited natural tannin content in the birch worked well for us. If you want a darker color on low-tannin wood, black tea (which is naturally high in tannins) can be applied to the wood prior to the iron acetate solution for a much darker color.
Preparing the Solution
I started with a pint of vinegar and one piece of steel wool to test to process. I put the steel wool in a mason jar with the vinegar, covered it part way, and left it for 24 hours (lesson learned: shake or stir the mixture several times to speed up the reaction). The lid should be loose in order to allow oxygen into the reaction. Make sure to use a nonreactive container that you’re fine sacrificing to the project. The reaction leaves rust marks on the container that are hard to remove. The solution, not surprisingly, smells like rusty vinegar. If you aren’t keen on vinegar smells, you may want to do this in a well-ventilated area. That said, the resulting countertops have no vinegar smell whatsoever.
After a few hours, you’ll see many bubbles in the vinegar and partially dissolved pieces of steel wool sinking to the bottom. If any of the steel wool is exposed to the air, it will be very rusty. This is normal. After about 24 hours, the solution will be ready for testing. Remove the steel wool from the vinegar solution to stop the reaction so your test will be consistent with your actual application. The solution will look light gray or brown in the jar. Note: this solution will stain clothes, wood, any many other organic surfaces so take necessary preparations to lay out drop cloths and wear old clothes as necessary.
Testing the Process
To test my iron acetate solution, I used an old rag to apply the liquid to a small scrap of butcher block. The initial reaction is very anticlimactic, it pretty much looks like you wiped a wet rag on the wood. Unlike stain, you have to give the reaction time to occur. After about ten minutes, you’ll notice the wood has turned darker. In my case, the initial test yielded a dull gray color, not the warm, rich, vibe I was hoping for. I felt a little disappointed that this technique wasn’t going to work, but then I noticed the residual vinegar in the jar where I had placed the rusty steel wool after removing it from the main solution. That small amount of vinegar was much darker. I applied it to another section of the test piece. Ten minutes later, voila! The wood had turned a warm, medium brown.
My initial solution wasn’t strong enough, so I put the steel wool back in the jar to keep reacting. At this point, I also mixed another pint of vinegar with several pieces of steel wool to be sure I had enough for the project. If I had used a bigger jar, I could have added it to the existing mix. I stirred both jars frequently throughout the day. By the next day, the original solution was dark brown and the second batch was light gray. I mixed them together in a plastic tub (without the steel wool) and applied a final test. We tested the ebonized sample with a coat of Howard Butcher Block Conditioner. This blend of food-grade mineral oil and natural waxes provides a barrier to moisture soaking into the countertops and brings our the natural grain in the wood.
Sanding the Counters
While the test solution was reacting, Josh and I prepared the butcher block slabs. Because this and many stain treatments can raise the grain, we sanded and the counters twice using a 220 grit sanding block then using a 320 grit sanding block. We wiped the counters with a wet microfiber rag after the first and second sandings.
Applying the Final Finish
Once the slabs were sanded, and the finished solution tested, we were ready to apply the iron acetate to the counters. I didn’t wear gloves during the test applications but highly recommend them once you start the large scale application. The solution can stain your hands in large quantities leaving your nail beds and callouses looking like a self-tanning application gone awry. We applied the stain outside on the driveway to avoid splashing the floor, walls, or cupboards. Because the amount of color is limited by the wood’s tannin content, you don’t have to worry a lot about even coverage like you wood with stain. Wipe the counters with a rag dipped in the iron acetate solution as if you were cleaning them with soapy water. Be sure to get the edges. Applying many “coats” will not result in a darker color once all the tannins have reacted. If one spot seems a lot lighter than the others, you can try wiping it again. If you didn’t get good coverage the first time this will remedy the light spot but bear in mind that, especially with butcher block, the varied nature of the composite slabs will result in natural light and dark spots.
Once the iron acetate solution was dry to the touch, we applied a generous coat of Howard Butcher Block Conditioner. This really emphasized the grain in the wood and revealed a darker, warmer tone. The counters will feel greasy (and a little slippery) after this application, but the oils will continue to soak in over the next 24 hours.
Putting it Together
The last step was to put the stained, dried, and oiled counters into place. We secured the counters from below using wood screws at the same attachment points where the previous laminate counters had been screwed in.
Here’s a look at the finished counters (and almost finished kitchen). I love the color! You can also sneak a peek at our freshly painted cabinets and new appliances. More on that to come…
I’d love to hear about your experience with countertop renovation projects or alternative wood stains. Have a question I haven’t addressed? Leave me a comment below.