Tile/Glass Cutter

Just wondering what sort of life span one could expect out of a tile/glass cutter bit for an electric drill? We just drilled two holes through our tiles last night to mount the toilet cistern and the drill bit is absolutely buggered. Don't think we'll get another hole out of it - and considering these bits come in at the dearest drill bit around I don't think you get your money's worth out of them.

Hi I use a spear tip also you might want to use it with water I just get a cup drill a little dip it in the cup of water and keep going trick is to not let the drill bit get hot hope this helps you

i used to have a hose trickle onto the glass when i was a glazier to prolong the life of the bit and reduce the chances of the glass cracking. i guess it would work the same with tiles.