Tile cutting

I have a new Mapei tile cutter which etches and breaks smooth glazed tiles easily. My problem is cutting heavier glazed floor tiles that have a patterned surface. They are almost smooth and about 5/16" thick. I etched them with one pass on my cutter and when I tried to break them they were breaking perpendicular to the cut. I suspect that I am not etching them deep enough. The cutter etches with very little force. I'm afraid of breaking the tile while etching it if I press too hard. Is it ok to etch more than once or should I just apply more pressure the first time? Also not sure about where to apply the breaker on the tile. Usually I do it near the edge. Does the same rule apply to larger tiles or can I break them more towards the middle of the tile? I cut a lot of glass which you should only etch once or risk an off line break and always start the break from the edge. Any input would be appreciated. Thanks

Since when does Mapei make or sell tile cutters?

The way to score and snap with a cutter depends on the cutter. Do you have a link to a picture and description of it?

Jaz

I don't really know about Mapei cutters aside from the fact that I have one. It may be old stock if they are not making them today. Since it is all cast iron it may very well be an older model. Everything I see now is cast aluminum or stamped steel. I found this one on eBay about 2 years ago among all the cheap Chinese cutters. It was brand new and I have only used it for the first time recently. The Mapei name is cast right into part of the frame. It is a double rail 20" professional cutter, all cast iron with chrome rails and linear ball bearings. The push handle is also cast iron and is curved. It has a measured guide/stop which only does 90 degree cuts. While on this site I watched a video on using this type of cutter. I used it as they have shown so I guess my problem is just not applying enough pressure when scoring. I will have to practice on some scraps to get the right touch. Anyway any input would be appreciated. Thanks