Tile and Glass Drill Bit (4mm)

It is worth being specific about why, because the instinct is exactly wrong. With most drilling, if progress is slow you speed up. With tile, speed is what stops progress. The carbide tip removes material by abrading it, and abrading generates heat with nowhere to go, because tile and glass conduct heat poorly and the tip is buried in a small hole. Get it hot enough and the carbide loses its edge, and a blunt spear point will not cut glaze at all. It then rubs, which makes more heat, and within thirty seconds the bit is finished and the tile is scorched.

So: the lowest speed you can manage, steady light pressure, and no hammer action ever. A cordless driver on a gentle trigger is better than a big corded drill at full speed.

The other thing that saves bits is keeping the tip cool. A little water in the hole, a wet sponge held against the surface, or simply pausing every few seconds to let it cool will multiply the life of the bit several times over. On porcelain it is not optional.

It is also worth knowing how to tell when one of these has died, because a blunt tile bit behaves like a hard tile and people blame the wrong thing. A sharp spear point produces a fine powder and makes steady progress. A blunt one produces almost nothing, the tip looks polished and rounded rather than sharp edged, and the drill simply sits there. At that point more pressure will not help and will crack the tile. Carbide can be touched up on a silicon carbide or diamond wheel if you have one, since an ordinary grinding wheel will not cut it, but for a bit of this size most people simply replace it.

Four millimetres is the size for standard wall plugs behind bathroom and kitchen fittings, small brackets, mirror fixings and towel rails.

The tip is YG6X carbide on a medium carbon steel shank, with a 1/4 inch quick release hex shank and a sand blasted finish.

Buyers are tilers, plumbers, bathroom and kitchen installers, shopfitters and hardware shops.

Message 94 77 111 8880 and tell us whether you are drilling ceramic or porcelain, and we will say what to expect. We deliver anywhere in the island.