The hole is almost never exactly right the first time. The core bit gave you 50mm and the drain needs 60. The faucet cut-out is drilled, but the exposed edge is raw and chipped. And enlarging or cleaning up a hole in porcelain or granite by hand is slow, imprecise, and one slip from a cracked tile. The Crowne "Big Boy" Diamond Chamfer Cone is built to make that job fast, controlled, and clean.
It's a tapered diamond cone spanning 35mm to 75mm, so a single tool covers a huge range of hole sizes. Sink it into an existing hole to open it up to the exact diameter you need, roll it around the rim to bevel and chamfer a clean, finished edge, and use the taper to shape inside radius corners or carve the rounded indentations that let a pipe or wire line sit flush. The high-grade diamond coating powers through porcelain, hard ceramics, granite, marble, and stone — the materials that dull or defeat lesser tools.
Think of it as the finishing half of the hole-making workflow: drill the hole first — a guide like the Crowne Tile BullsEye keeps that start clean and on-mark — then reach for the Big Boy to size it, bevel it, and refine it. It runs wet or dry and threads onto a standard angle grinder. Crowne builds it "for pros by pros," and you feel it in how much hand-filing (and cursing) it eliminates.
Pro tip: Let the diamond do the work with light, steady pressure and keep the cone moving — leaning on it or dwelling in one spot builds heat and can chip the glaze. Sneak up on your final diameter rather than forcing it in one pass, and keep water at the contact point when running wet (or pause to let it cool when running dry).
