The tile drill bit is good but in my view unnecessary it’s a spade-like shape. Guess if you want piece of mind you could get one.
Tbh, I only every use a good masonry bit or those multi construction bits as they are a bit sharper angle and I have never had a problem. I used the masking tape but didn’t quite get on with it.
It’s essential to just tap a nail or screw (shaper point) into the tile to chip the glaze as bit will wander everywhere and scratch the tile. I did it on my first time
Let the drill grind away on slow speed and low pressure and its no probs.
I have only ever tried it to ceramic floor and wall tiles, (never porcelain) Floor tiles are harder to drill but just take your time and don’t use too much pressure.
I never had a problem but only ever drilled about 10 holes even in hollow sounding tiles (maybe 10 practice holes as was worried it would crack the tiles)
PS: don’t remember to switch hammer action off!
