Always use lubrication (water) , if not the diamond core will over heat.
Use for conventional power drills on the low speed setting with the hammer action disabled.
These are auiable for drilling ceramic tiles, glass, marble, slate and porcelain tiles up to hardness grade 5
If you're drilling on a vertical surface try a hand spray water bottle, or sponge soaked in water and held underneath, but in contact with the drill bit.
Keep the bit as wet as possible during operation, if the bit dries out during use it will overheat and immediately blunt
How to use:
Clamped firmly to a bench to allow for slow controlled drilling.
If drilling in situ or at an awkward angle, cna try following method:
Make a template from a piece of timber or waste material, locate this over the area where you want to drill your hole and use it as a "guide" to start the hole.
Once you've got into the surface by 1mm to 2mm you can remove the guide and continue to drill in a controlled manner.
Start your hole diagonally, make a round trace and then hold drill straight