Drilling porcelain

Anyone who has ever tried drilling porcelain knows how tuff it is. Any good ideas how to do it?. I use Milwaukee’s diamond hole saw (usually 1/4 in) with water it’s pretty decent (though it’s impossible to remove material from inside of the bit).
Does anyone have a better/easier way?.

Diamond core drills that are meant for drilling glass will work. We used to create a circular dam around the hole with plumber’s putty and flood it with water. There are also solid shank drills meant for drilling glass


We used ones from Regent Stone, Supreme (Hilton Diamond Tools) and Q-4 (Dia-Pro) - all with 5/8-11 threaded arbor for use with a small grinder.

You might also try a Bosch Glass drill:


but in this type drill bit I prefer a spear-point design such as supplied by Cintride (or the old ones from Red Devil)


Thanks, I’ll look into them.
Regarding the Bosch set I’ve tried them. They work fine for one hole, and then they melt, or crack and you have to figure out how to get them out of the hole. Bosch specifically writes that it’s meant for glass, not stone or porcelain (porcelain is much harder than most regular ceramics).

We used the QEP diamond hole saw with water for one whole when we redid our bathroom. I wanted to try the Bosch but stupid Amazon had a delay in shipping it and the QEP was all Home Depot had. Worked fine I guess

I use a
PTC ARMEG Carbide Tile bit 5/16 when drilling into porcelain

we use it to put the Doorstops onto Tile or for installing shower rods

I just use my M12 drill with a bottle of water a cap full per hole seems to be all i need on the floor and I can drill 3 holes on a full charge 2mah battery and still have some charge left

I have probably drilled close to 100 holes on the current bit into porcelain and its still going strong and I have probably spent 200 or more on every other bit out there

Do they sell them in the us

@ David

“Do they sell them in the us” I assume you mean Armeg PTC Bits sold in the USA

Amazon has them - a bit pricey - pun intended - with typical Amazon “not exactly free” shipping built in


We used to buy from a company called Tools4Flooring - cheaper but you need to spend $75 for free shipping:



I took a look at Amazon - they are selling the Armeg bits via Contractor’s Direct. Depending on how many you buy - you may be better off buying directly from them:


I’ll check it out

that is indeed the bit I was refering to the trick i find is once you start the hole to move your drill around in a small conical circle and so it “bites” into the material as you go and doesnt glaze the porcelin over if this make sense.

that is opposed to pushing straight down and waiting for it to drill through

Don’t use your drill in hammer mode if you want the bit to last and just make sure to keep the bit as cool as possible I usually drill the hole part way add a little water to the hole and keep going

if your drilling vertically a spritzer bottle works well enough

hope it helps


DeWALT diamond drill bits for tiles are the best, Made in UK. If you use them with water always, you can make more than 50 holes with one bit. Also it is easy to remove the round piece of tile from them.