I created a walnut butcher block island top. The customer has been using it and treating it with mineral oil for 6 months. They have now requested that I assist them in "sealing" the top (basically creating a non-oily finish) so there is no longer any oiliness on the surface. I don't know of any way to put another finish (one that would seal the top) on this wood that has had multiple treatments with mineral oil. Any suggestions?

Hi Doug,
I kinda doubt that there is any way of "sealing" that top with anything, at least not for several months, and maybe much longer. That mineral oil will be well soaked in and I am highly suspect that it will not let anything stick to it which means what ever you coat it with will never really dry properly, it will just sit on top and just get wiped off.

If you let that top sit, and do nothing to it for ???? many weeks ??? or months ???. It possible that the the mineral oil will soak in deep enough that some time in the future, you "might" get a product to stick to it.

I have tried coating pre-oiled materials in the past without any luck .. hopefully you will do better, or maybe someone else has an idea or new product that might work.