If you have ever tried to make a smooth curved cut in a super-hard porcelain floor tile, you probably gave up. I almost did. I needed to make very accurate semi-circle cut at a side of a tile that goes around shower drain. No tools allowed performing this task. All professional tiling specialists (I asked at least 5 of them) suggested nipping the tile, saying that that was the only way to do it.
All rotary cutters, INCLUDING THIS ONE, would say "Do not use on floor tile". Well, you would not be able to do the job using ONLY this diamond cutter, but wait, there is a solution that worked unexpectedly fine for me.
Follow these steps:
1. Draw a cut-off line on the front side of you tile with a pencil.
2. Using a rotary tool with variable speed capability and this cutter, work along the line making superficial groove (1/16 of an inch is enough). IMPORTANT: use low speed setting (up to 8000 RPM), otherwise the cutter will overheat momentarily; work for no longer than 3 seconds at a time, then just let it idle for another 3 - 5 seconds to cool off.
3. When you are done with the groove, set you rotary tool aside - you won't need it anymore - and use a wet saw to make parallel cuts every 1/4 of an inch. Cut it all the way up to you groove. When you're done, you can snap off cuts strip by strip at the place where your groove is, which will result in ideally precise cut on the face of your tile.
THE BOTTOM LINE: no other tool can be used to make a precise inner curved cut in a floor tile.
Smart, isn't it? :-) And I'm not even a pro!