Cutting tile on backsplash

I am replacing my over the range microwave. I want to mount it directly against the wall, but I will need to remove about 8 inches of the top of the existing tile backsplash in order to get it back against the wall. The backsplash is 6" tiles in mortar. The cut would be across the center of a row of tiles, and up to the top at the sides. How would I go about doing this?

Depends on whether they're relatively soft wall tile, or a floor tile on the wall. Do you have any spare tiles? If you do, the safest and probably neatest is to tear them off and install new ones.

If they are soft wall tiles, then something like a RotoZip with a tile bit can cut them fairly quickly. To get a straight line, you'd probably want to put up a straightedge. If they are floor tiles, it'll be tough cutting a clean line. It will be very dusty, and harder to get a clean straight line. You'd need a drycut diamond blade, and though to do on the wall, or a diamond cup wheel.

Check out www.johnbridge.com to see if they have any other ideas.

The easiest approach would be to use an angle grinder with a dry diamond cutting wheel. You should be able to cut a straight line fairly easily that way. Don't forget the dust mask!

Ditto on the angle grinder option! I had the same problem with a new microwave that was just a titch taller than the old one and I used an angle grinder to cut off about 1/2 inch of the splash tiles. Basically I created a 'tent' of plastic sheeting to contain the dust, put on my dust gear, entered the tent and went at it. It was very fast and very accurate. It took longer to set up the dust tent than it did to do the job. My new microwave had a indented lip on the back edge that fit nicely over the tiles, completely covering up the cut line.