Porcelain tile cutting - round shank bits in hex drill/driver

[longbloke23]

Hi. I need to cut a couple of round holes for pipes and a few holes for shower screen door screws, into 9mm porcelain wall tiles. The diamond drill bit sets (for round holes and screw holes) that I've seen (for a reasonable price at least) are all round shank and I have a hand tightening hext drill/driver only. I'd prefer not to spend a lot as I'm not expecting to need to use the drill bits again in the foreseeable future.
Wondering whether round shank bits will be OK or whether they're likely to slip. I don't really know whether you drill lightly into porcelain, in which case should be fine and unlikely to slip, or whether I'll need to press hard in which case worried the round drill bit may not be gripped in the driver.
Thanks for any advice

 

[mrrusty]

For a few holes, buy good quality diamond bits - they will be £15-20 for the small sizes and more like £30 for pipe size. In your cordless drill start with the heel of the drill on the surface and the edge of the bit touching at about 45 degrees. Get a firm grip. Start cutting. As soon as it digs in you can carefully ease the drill upright to drill through. Doing it this way it is far easier to control and helps prevent the bit skipping across the surface of the tile. You don't need much weight - letthe diamonds do their job.

Forget the cheap bits. They are rubbish for porcelain.