Finishes for Decorative Butcher Block

In search of a durable finish for a non-working butcher-block cutting board. January 29, 2009

I finished an end grain maple butcher block counter-top. I used an Olympic water-based polyurethane. I sprayed the finish directly over the raw maple and everything looked great when I was done. Now it's six months later and as you can see from the picture, the finish is lifting at the joints.

I will refinish the piece but I want to understand the problem before I do this again. Do you think the problem is adhesion, lack of flexibility (i.e. too brittle of a finish) or some combination of both?

My requirements for a finish are that whatever is chosen imparts no color onto the wood and that it is durable enough to withstand normal wear and tear as an island counter-top. The butcher block is not used for cutting - it is decorative only.

I am thinking about trying out Target's 9300 Polycarbonate finish. Does anyone have any thoughts?

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Forum Responses
(Finishing Forum)
From contributor G:
Looks like glue from here. Is that the top or bottom of the block?

From contributor J:

I would not recommend applying any type of polyurethane material. To keep your butcher block counter top protected and beautiful you should use a product called spoon oil. It is a mixture of bees wax and mineral oil. Since we can't advertise you can email me and I'll tell you where to find it. I have restored two butcher blocks with it. One of them we use as an island in the kitchen.

From the original questioner:
It's not glue but rather the poly flaking up from underneath. The darker staining outside the flaked poly is a result of water/dirt seeping through the cracks in the finish.

To contributor J: What kind of finish does spoon oil leave? It was important on this project for the block to have a satin to semi-gloss sheen to it. The homeowner didn't want a flat finish like a working BB would have. I was also concerned about an oil finish ambering the overall color of the block.

From contributor C:
You have a challenging project there. That type of structure is moving too much for the finish to follow. It also appears to me that your original finish did not penetrate the surface much at all. That’s strange since that end grain should be very thirsty. I have little regard for most water based poly finishes and wouldn't try that again if I were you. I'd likely use some Kwik-Poly on that as it would soak way into the grain and help with stabilizing the joints as well as sealing out moisture.

You have to work quick with Kwik-Poly and sometimes split up the area a bit but use it as a wipe on (you can pour it on but spread it quickly and wipe off the excess before it hardens) and do two or three coats and then you can sand to the sheen you want or coat over it with whatever you like (I'd recommend Clear Satin Breakthrough).

If at all possible you should also finish the bottom of the BB counter in a similar manner as otherwise moisture from the air might cause problems. This type of assembly is exceptionally vulnerable to movement problems. You need every edge you can get. Also be sure to get all that moisture out of the wood before refinishing.

From contributor J:
To the original questioner: it will provide a satin to semi-gloss sheen initially however it may dull a bit several months down the road. Initially it will also make the wood (maple in my case) tint to the amber side initially. After some time the butcher block looks normal. It is important to note that this isn't a onetime finish. Depending on how much the area is used it will have to be maintained every so often. It's been almost a year and I don't have the need to add anymore spoon oil yet.

From contributor T:
Can't help you with your finish selection but I would offer this: moisture content changes cause maple to expand/shrink twice as much in a direction tangential to the growth rings as it does in a direction perpendicular to the growth rings. When the growth ring orientations are as varied as they are in your picture, you're going to have relative movement if there are changes in moisture content. It appears that is what has happened here.

It is important to minimize the exchange of moisture with the environment by first finishing the bottom as well as the top and second minimizing humidity changes in the environment itself if possible. Is there a dish washer in the area? They pump out a lot of humidity when the dry cycle is used.