Mike, I bet many cutters have tried using a tile saw. I tried it when I first started cutting, but as explained by another commenter above, the blade was thick, so I wasted rough. I also had difficulty getting a good straight cut.
After I could afford it, I picked up an Ameritool trim saw. Works great – I recommend a scintered blade.
Also – Ultra Tec offers a facet saw adapter. It comes with the .006 blade and an adapter to keep it flat on the machine. This works amazingly well for trimming a Trilliant. You can just dial in the right angle, and in 3 cuts, you have a preform…almost ready to go to the 1200 grit. I demonstrate it in an upcoming video on YouTube in my Gem Cutting Tutorial series. I won’t be out for a while…I’m behind on editing the videos and am swamped with cutting for my wife, Bopie’s store.
Bottom line: I don’t recommend a tile saw, unless as stated above you are cutting large chunks of inexpensive rough (synthetics, lab created, Smokey Quartz, Clear Quartz, or the like. If the budget is limited, I’d recommend the Ultra Tec facet saw adapter. Then when you have enough budget, a 4″ trim saw. I only have experience w/Ameritool…and love it, but I bet there are many other brands out there that are also excellent. I don’t live near a Faceting Club, but another option would be to use the club’s equipment. I visit the Old Pueblo Lapidary Club in Tucson almost every year during the gem show days, and they are an awesome club with great equipment and super people!
Wishing you all the best!