12 Pcs Diamond Drill Bits for Ceramic, Diamond Hole Saw Drill Bit Set Kit, Premium Glass Drill Bit for Bottles, Pots, Marble, Granite Stone, Tile Cutting 0.16 Inch - 1.18 Inch（4 mm - 30 mm） YLYL

I have lost a few pots and plants due to holding too much water for lack of drainage holes. I was a little nervous to drill, but they worked! At first I tried to drill straight down, but my husband tipped me off to angle the bit and do one edge first to bite in, then bring upright. Worked great!I did get a couple chips on the edges, but it's the bottom of the pot, and no cracks, so no big deal. Probably user error than the bit. I did 6 holes with one bit, could probably drill a few more, so I'd say that they are fairly durable. The pack is a good value for number of bits.

Work as advertised. Very good value. Use them correctly with proper drill and your results will be fantastic.

The set works like a charm, the reason I’m giving 4 stars is because the condition I received them in. As the image shows the bag is covered with rust, but again other then that set work great, used it on pottery cuts without issues. Easy to use, works with any standard drill.

Understand that these are all in metric sizes and this purchase was for the smaller sized bits. There are many sizes to choose from in this kit, from I think 3mm or 1/8 inch equivalent up to I think 24mm or like 7/8 inch. The sizes are laser etched on the shafts and are a little difficult to see, but the holes that they make are relatively smooth rather than just a sharp edge. The reason is that the bits are simply metal tubes that have one end dipped with metal covered crushed industrial diamond, much like sprinkles on an ice cream cone. With this said they are not lab quality sized bits, and have some cutting surface disparity due to the various sizes of chunks around the end, and this disparity will create a more rounded or smoother edge on the hole that you cut through the glass. Start out slow and at an angle with just the weight of the bit against the glass, and spin the bit against the glass until a little edge develops (I used a rechargeable drill), then add a few drops of water and start to reduce the angle and the edge starts forming a circle on the glass. Slow and steady wins the race!! This is glass, and super tiny pieces of glass are now being broken off of what ever you are drilling through so wear a mask, and have a removable work space that you can just wipe and clump up into a ball and throw away, like some damp newspaper that the wet paper will keep the super tiny glass fragments/shards from blowing away and you can just crumple up and throw away the mess with minimum wiping. With this set I managed to drill a 1/2 inch hole in the side of an aquarium for a water overflow, on one of those 2 1/2 gallon rectangle super thin glass aquariums with the black plastic frame, that still had some fish in it (do not recommend this). The hole was a success, the fitting has been installed and still the aquarium has fish in it (that suspect nothing.) Slow and Steady, listen to the screeching of the bit against the glass, if too much screeching you are either too fast or pushing too much. Slow down, add a few drops of water, and then continue on until you start to see the point where the water starts running down the glass on the other side, then slowly continue on until you have a hole drilled through whatever it was you were drilling. Note: I do not know what it would do to tempered glass, from what I know this would probably shatter any tempered glass the instant the bit scratched the surface. My use with these bits has been just plate glass and bottles. Good luck.

These work great! I have not broken a pot since I got them. I run cold water then this. Doing this every 10 seconds or so. Clean cuts too.

So this is a moderately priced set of bits. I would say if you were a casual user or needed it for a one time use these are the bits for you. I use them to cut glass and they work pretty good. The only thing I can say is that some of the drill bits are off center and wobble. Two of the drill bits did not have any cutting surface on them right out of the package. But over all if your not using them every day on a job site these are perfect for the weekend hobbiest.

Wanted to try using this diamond drill bit on a ceramic bowl which is much cheaper and better quality than most planters being sold.We flipped the bowl over so we have access to the underside. Added a small layer of water on it before we started drilling at about a 45 degree angle. It slips a lot so I had another person holding the bowl steady while I had both hands on the drill. One to keep it from slipping so easily and the other to keep it steady applying light pressure. Started drilling slowly but didn't have much of an effect so I had to add some speed gradually before we created an indentation. Once there was an indent, I just put the drill vertical so it can drill a hole straight through. Again, started off slowly and gradually increased the speed also making sure we have enough water. Was able to get the hole drilled through. Not perfect but can't complain.Didn't really keep track of time, but it probably took us 2-3 minutes to do this. The drill bit looks a little bit worn after this so not sure how many more times we can use this drill bit.

Used these on my ceramic planters and the worked out great. There was a variety of sizes which is very handy. made out of good quality material for what I needed it for.