Drill porcelain, that is, a porcelain tile mighty be one of the hardest drilling jobs yet. It is considered hard, because if you make just one false move, one slip, you will make a crack in your tile and it won’t look pretty. But if you are familiar with a technique it will not be a problem for you.
Porcelain is much harder, and highly denser as well as much heavier than an ordinary ceramic tile. So drilling out ceramic tiles and porcelain tile is not the same thing.
For drilling porcelain you will need good quality diamond core drill bits, a carbide pilot drill bit (if you are drilling large diameter holes, 13mm or larger and you can’t find a suitable size of a diamond drill bit – 8mm), masonry drill bits along with tile drill bits, water cooling equipment , an electric drill and of course safety glasses / goggles. You can also get an anti-slip guide plate just to make your job much easier.
Ready, set, go!
By using a marker or a sticky drive pad you mark the center of the hole you need to drill. If you have an anti-slip guide plate you just place it on the correct place on the tile and place the diamond holesaw into the correct hole and press the drill bit up against the porcelain ceramic tile. Slowly drill for between five and ten seconds, you do not want to build heat into the holesaw. After you remove the anti-slip guide plate and the drill you see a shallow hole in the tile and that will be your guiding hole.
If you don’t have an anti-slip guide plate, just place the appropriate diamond core bit on the electric drill and make sure that there is a continuous supply of cold water that is applied directly on the bit by using water cooling equipment (using a sponge or a aspirator is not advisable because it will not cool the bit enough and will shorten the life of your drill bit).
Set your drill in normal mode and start your drilling.
If you are using a diamond drill bit use the method called leaning in. It will ensure that you won’t slip and wander off the center as you drill into the porcelain tile. Apply sufficient pressure and go slowly until the dill changes its sound. Replace the diamond core with the appropriately sized masonry drill bit and set the drill to “hammer” mode and finish the job.
If you are drilling with carbide drill bits you need to keep them cool because they overheat very quickly. And push the drill bit very gently with sufficient pressure until you hear the change in the tone of the drill. After that stop, and take a masonry drill bit and set the drill in hammer mode. Use slow speed and frequently withdraw the drill bit.
Please only use enough force to keep the drill working and never over exert pressure or the tile will crack or split. Never let the drill get hot because the heat kills the glue bond holding the diamond, so always keep it cool. Always wear protective gear, including safety goggles and never apply pressure for too long.