Guides

Drilling porcelain stoneware without chipping

Porcelain stoneware is hard, dense and unforgiving. With the right diamond drill bit and the right technique, you can still drill clean holes for electrical outlets, fittings and fixings.

Why standard drill bits aren’t enough

Porcelain stoneware is harder than most natural stone and absorbs hardly any water. A masonry drill bit with a carbide tip quickly becomes blunt in it or can crack the tile. Diamond tile drill bits grind through the material instead, without hammering. So always drill with the hammer function switched off.

Choose the right tile drill bit

For holes from 20 mm, such as for electrical outlets or pipes, use tile drill bits with an M14 connection for the angle grinder.

For small holes from 5 to 14 mm, such as for wall plugs, there are tile drill bits with cooling wax. They have an M14 connection or a HEX shank for the cordless drill.

Step by step

Here’s how to drill clean holes:

Mark the drilling point and use a drilling template for large holes
Start the drill bit at an angle until a small groove forms
Then slowly straighten it and drill with light pressure
Work with gentle circular movements so the diamonds can cut freely
Reduce the pressure further just before breaking through

Don’t forget cooling

Heat is a tile drill bit’s greatest enemy. In drill bits with cooling wax, the wax inside melts and cools the cutting edge. For large diameters, take short breaks to let the drill bit cool down. If you smell burning or the drill bit changes colour, it is too hot.