My New Blog: TF Workshop

Saturday, November 18, 2006

Granite layout, cutting, gluing, testing...

I needed to take a quick break from the cabinets to get a few cut pieces over to the fabricator to put finshed edges on them. These are for the drop-in sink and the island. Delivery time is about 3 days, and I would really like to have them before the Thanksgiving weekend.

Here is the granite layout plan:

I decided not to try to cut the large tiles on my tile saw - it's too risky. The granite between the blade and the fence would likely crack. At $66 a piece I really didn't want that to happen. I bought a 4" skill saw for tile from HD for $45 (Workforce THD250). The saw worked great - really clean cuts. I cut the sink pieces 1/4 large and then re-cut them on my tile table saw, to get them exact.

I am planning in using polyurathane glue to install the granite. I have used it on tile and slate, and it worked really well. I have installed a fair amount of tile and lots of brick and stone (used to work in masonry), so working with morter and thinset is not an issue. I want to bond the granite directly to the wood, so I dont have to add the 1/2 thickness needed for backerboard and two layers of morter. Also, the poly will bond the granite diretly to the undermount sink, and give good water proof seal. Finally, the poly has an "open time" of at least an hour, giving me the chance to make sure everything is exactly right.

So I did a couple of tests... I bought some cheap pink granite and setup prototypes (yup, I'm an engineer). I tested the bonding strength of granite to plywood and granite edging.

Both work excellent.

I spread the glue on about 1" lines on the plywood. This glue foams up, so it needs some place to go, or it will raise the tile. I let it dry about 8 hours. I broke off the granite edge with a hammer both in the upward and downward directions. In both cases it broke at the glue line - in other words, the glue bond is stronger than the granite itself.

For the edge glue, I tried to break it by hand - no go. I can't break it. I have done a lot of edge bonding like this with thinset - it breaks pretty easily. This is definately a superior bond. I am going to back-up the edge bonding with a piece 3/4 x 1 wood, glued in place.

I will bond the edging to the tile before install. This way I can get them exactly right, and not depend on the face of the cabinet to align them. If you notice a poor tile job, it often is due to the front edging not being quite right.


donutboy said...

be careful using that saw! it is not UL approved for wet conditions. I really don't know how HD continues to sell that.

TTFWEB said...


Thanks, I will be careful.

However, I need to disagree with you. It has an integrated water feed and the package indicates its UL listed. UL would have had to approve the entire design, including the water feed.