Ginjaninja wrote:Dannie Boy wrote:Therein lies the problem, you really do need a hammer action drill.
I've never drilled through tiles before so consulted YouTube and the vidoes advised not to use the hammer-action as it may crack the tiles.... I think I'd just prefer to get the correct bit so will check out T.W. and that toolshop Bristolian was referring to.
Unless of course someone nearby has a bit they can lend me.
GN.
maybe I was wrong withthe hammer action - some useful advice here
Tile Drilling
Note that a variable speed drill is very useful for this task. Many "ordinary" (i.e. glazed pottery style) tiles can be drilled with a masonry bit. Basic dedicated tile drill-bits, have a flat spear shaped head, and a plane shank with no flutes.
Start drilling by placing the point of the drill against the tile and pushing hard. You should hear a slight crackling sound as you puncture the glaze at the point of the drill-bit (if the whole tile cracks then that is an indication that it was not "bedded onto" the tile adhesive correctly!). Now start the drill and use a slow speed with more pressure than usual. The drill-bit should cut through the glaze and into the tile backing. Once through the glaze you can speed up the drill. (Don't use hammer action until you are through the tile and into the wall). If you are using a special tile drill-bit, then it is better to swap to a more appropriate type of drill for the material behind the tiles. Don't use the expensive tile drill-bit for drilling the masonry or whatever material is behind the tile!
Some tiles (especially porcelain ones) are very hard, and consequently very hard to drill. If you try to drill one of these using the above method you will have a very hot and useless drill-bit before you are even through the glaze on the first hole. Water cooling is essential. Either use the dam technique described in the section above on glass drilling, or use a water spray (the "pump up" garden variety is good for this. You can also get sprays designed for the purpose that have a collar fitted to the spray head to mount on the nose spigot of many drills.
For the hardest tiles you may need to invest in a professional tile drill-bit with a solid carbide tip. These typically cost over £20 each and may only last for 15 holes! They must be used with high pressure (25kg of weight behind the drill is common), with water cooling, and with a closely controlled speed - often between 700 and 900 rpm. Read the manufactures instructions carefully since you are paying over £1 a hole even if you look after the bit so that it enjoys a long and productive life!
If that all sounds like too much trouble then consider using a diamond disc in a small angle grinder to cut around the thing you were planning to drill a hole for!