Expert: Jamie Yocono - 2/24/2008

Question
Hello Jamie. I have read an answer you submitted and found it to be very helpful in my situation.
( http://en.allexperts.com/q/Cabinets-Furniture-Woodworks-1468/Inlaying-tile-wood-... )

I am in the final stages of completing one of my most difficult projects ever, A custom kitchen floor to ceiling cupboard with bread box. In my design is a drawer, on the face of this drawer I am incorporating a natural stone inset in a red oak. I have routered out the red oak to accommodate the stone. (stone matches the backsplash in the rest of the kitchen). I sure wish I read the article mentioned above before attempting to "mortar in" the tile. Needless to say, thinset mortar isn't as thinset as I thought!! The oak cracked and wood warped and split from the pressure. OK, so I'm onto my second try, I have the new piece of red oak routed out and ready. I am going to use silicone caulk instead of mortar to adhere stone to oak, but the question I have for you is: Have you ever experimented with a silicone/sand mixture as a grout. I have thought of this a few ways, Actually mixing silicone and sand grout together or just simply silicone the joints and "dusting" the top to the silicone with the sand grout to give the appearance of a sand grout but still giving the "flexibility" I require. I would like to try and match the grout to the rest of the kitchen as close as possible. What are your thoughts or suggestions?

Answer
Hi Bryce,

Yes, I have experimented with mixing silicone caulk and sand and using it as a grout. I have done it both ways you suggested - mixing it together and applying it, or dusting the plain caulk with sand after it's in place. Both work reasonably well. Make sure the wood is finished before you do this, as the silicone can enter the pores of the wood and stain it.

The problem I see with what you're doing is that you're attempting to adhere something that's not going to move (the stone) with something that CAN move, the wooden drawer face. You have two opposing forces, one of them has got to give.

I would suggest a couple of things.

If you can reduce the size of the stone, so that you have more wood surrounding it as a border, you might reduce the chance of cracking. I think a larger border of wood will be stronger, and less likely to split when it undergoes the eventual movement it's going to experience.

Is there a chance you could use plywood, with a solid wood edging for that drawer front? Plywood isn't going to move at all, and would be a perfect solution.

Finally, a larger grout line (of silicone and sand) would be more of a buffer for the movement. See, the wood is going to expand and contract. If the wood wants to move, and the stone doesn't allow it, then let a larger grout line absorb the movement. I might suggest a single large bead of caulk down the center of the stone, so that when the wood wants to move, it can move from the middle, outward. A larger grout line will also allow that.  It's just a thought.

Finally, the best solution I've found is a combination of flexible grout (to allow movement) and a good buffer (border) of wood, so that it's not fragile and easy to split. Regardless, I still experience problems from time to time. You're talking about two materials that couldn't be more different. Something has to give, you just need to do everything possible to minimize the chances.

Good luck, write back if I wasn't clear about something, or if you have more questions. Sounds like a nice project. If you're into it, I'd love to see a picture or two. You can send them to my personal e-mail account :  jamie@wooditis.com

Jamie Yocono
Wood It Is! Custom Cabinetry
Las Vegas, NV
www.wooditis.com
My woodworking blog: www.wooditis.blogspot.com