Warped Cutting Boards: Uh oh, my cutting board is bowed!
Hello All,
So it's happened... you have a cutting board, perhaps even brand new, and it has warped, it rocks on the counter, it wobbles on the table... what can you do? In the long term, we recommend some mineral oil and Bees Buffer to help keep your cutting board protected. But, let's say it's too late or it's warped anyway... well this is what this post is about! This process is about slow, gradual applications of water. Oh, and a quick note, do not ever *soak* the board in water. It voids the warranty.
I. Why?
First off, let's take a look at why this is happening. All of the wood we use, and most producers use, has been kiln dried which means that the moisture content has been greatly reduced. If you were to add water to just the top of this plank, you'd expect that area to expand and for the bottom to remain dry--that causes it to bow.
We flatten every cutting board before it leaves our shop, which means that the particular slab of wood has a specific moisture content at which it is flat. Alter that, and it'll develop a bow (and will likely eventually crack).
Because this is so difficult to really mitigate perfectly, we recommend stabilizing the cutting board on a dish towel. This will help hold the cutting board in place and reduce rocking. Some cupping/bowing is just part of the territory of a wooden cutting board. Why doesn't this happen to your furniture? Well, why doesn't it usually happen? Because cutting boards are regularly being exposed to a lot of moisture in a way that furniture just isn't.
Wait, what's that you say? but the warping so much worse? It isn't just wobbly, but it's the bottom of a rocking chair? Good News!
II. The Fix
You can actually fix this right at home. There are a few techniques but we'll only cover one here because the others involve steam and ironing and I think that'd be better demonstrated with a video.
So here's what we know: It's an issue of moisture content, right? One side is drier and the other side is wetter. Typically, the side with less moisture is the concave side. If you incrementally apply water to the concave side and do the unthinkable... leave it to soak in, that side should expand. Do it as necessary to balance it out.
III. An Anecdote of my own...
I'll end this blogpost with a little anecdote of my own from a year or so ago. We were working on a slab of end grain maple that measured 24" wide x 50" long x 4" thick. A lot of people will make the assumption that thickness wholly determines if a board will warp--nope! It's more an issue of simply going too thin. So when we're sanding our boards, we actually saturate them with water in between sandpaper grits (which determines how smooth your cutting board feels. you start coarse and go to finer grit). This raises the grain, so that way more grain is exposed, thus more of it gets sanded. If we were to skip this step, your board would feel drastically different after you washed it for the first time. Anyway, so we wet one side and let it be for 10 minutes. We came back into the shop and saw that it had bowed about an entire inch. Again, in ten minutes. Initially, I freaked out having never seen something this drastic. I calmed myself down after realizing that the board would even out once we got to the other side, and indeed it did. So the point here is: wood may seem hard or look geometric, but it's actually quite malleable in a number of respects. Remember that you're dealing with something that's practically alive, breathing (the irony of which isn't lost on me, since it is dead, afterall).