# Tell me the best way to cut holes in tempered glass **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [June 11, 2013, 11:18pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761 "2013-06-11T23:18:22Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Deeg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/deeg/32/2955_2.png) [@Deeg](https://boards.straightdope.com/u/Deeg)\ **Post date:** [June 11, 2013, 11:18pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/1 "2013-06-11T23:18:22Z")
I’m working on an art project that involves cutting ~ 1-inch holes in class tea cups and a tea pot. What are the best tools for this? It looks like I want some diamond-tipped drill bits but I have no idea what are quality bits. Does anybody have any experience in this area that can give me guidance? Thanks! ---
**Author:** ![Projammer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/projammer/32/559_2.png) [@Projammer](https://boards.straightdope.com/u/Projammer)\ **Post date:** [June 11, 2013, 11:36pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/2 "2013-06-11T23:36:15Z")
The good news, tea cups and teapots aren’t usually tempered glass. Otherwise breaking one would give you thousands of pea sized kernels of glass instead of 5 or 8 big pieces. The bad news, drilling glass is still tricky for the novice. For a hole that large you’re going to need a [glass cutting hole saw](https://www.google.com/search?q=glass+cutting+hole+saw&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a#q=glass+cutting+hole+saw). Amazon or eBay if your local hardware stores don’t carry them. It will also be much easier if you have access to a drill press to keep the bit stable and to apply consistent, steady pressure. In fact, I wouldn’t recommend even trying it without one because the saws don’t have a center guide bit to stabilize the outer cutting edge. But once you’re ready to go on, just remember to maintain a steady pressure and keep the cut lubricated with water or light oil. And practice on cheap stuff first. ETA: I’d hit youtube for instructional videos. A picture being worth a thousand words and all. The technique is pretty much identical for plate glass and ceramic tile so any of those would be good. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [June 11, 2013, 11:41pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/3 "2013-06-11T23:41:24Z")
Your local glass shop could drill these holes for you. If you do it yourself use a smaller hole to start and file out the sides of the hole to get to the right size. Drill from the top and put water or oil in the cups to cool it and act as a lubricant. It’s going to be tricky to do, get the glass shop to do it for you if you can. Do you absolutely have to put holes in them? ---
**Author:** ![Capt\_Kirk](https://avatars.discourse-cdn.com/v4/letter/c/779978/32.png) [@Capt\_Kirk](https://boards.straightdope.com/u/Capt_Kirk)\ **Post date:** [June 11, 2013, 11:43pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/4 "2013-06-11T23:43:21Z")
**Projammer** hit the nail on the head I used to work, briefly, in a lighting factory and had to drill holes in glass all the time. IME a one inch hole is a really big one, prepare to break a lot of glass. Seriously use a drill press. Good Luck Show us some pics when you finish, if you don’t mind **Capt** ---
**Author:** ![Deeg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/deeg/32/2955_2.png) [@Deeg](https://boards.straightdope.com/u/Deeg)\ **Post date:** [June 12, 2013, 5:17am UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/5 "2013-06-12T05:17:00Z")
Thanks guys, this is the kind of advice I’m looking for. > [@Projammer](#): > > The good news, tea cups and teapots aren’t usually tempered glass. Otherwise breaking one would give you thousands of pea sized kernels of glass instead of 5 or 8 big pieces. Ah, thanks. I thought all heat-resistent glass was tempered. > [@Projammer](#): > > For a hole that large you’re going to need a [glass cutting hole saw](https://www.google.com/search?q=glass+cutting+hole+saw&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a#q=glass+cutting+hole+saw). Amazon or eBay if your local hardware stores don’t carry them. Do you have any advice on what makes a quality bit? Amazon has one for $6 which seems awfully cheap. Is that going to last and make quality holes? > [@Projammer](#): > > It will also be much easier if you have access to a drill press to keep the bit stable and to apply consistent, steady pressure. In fact, I wouldn’t recommend even trying it without one because the saws don’t have a center guide bit to stabilize the outer cutting edge. Yup, got a drill press and a Dremel. I have access to a milling machine but that would be a major pain. > [@Capt\_Kirk](#): > > Show us some pics when you finish, if you don’t mind I plan on documenting it as much as possible and making it public. Here’s my project; if you have any advice or pointers I will gladly hear them. What I’m hoping to do is design my own ceiling light with 4-5 pendants. The pendants will consist of a tea service: two cups+saucers, tea pot, sugar bowl, and maybe a milk dispensor. They will be hanging upside down from a tea tray. Other than the tray they will all be frosted glass (I may end up frosting them myself). I’m going to take my time and hope to get all the components of the tea service from thrift stores and yard sales. That kind of stuff is generally cheap and I’m not too concerned with ruining a few along the way. I’m going to use [something like these](http://www.grandbrass.com/SearchShowItem.cfm?ItemNumber=SO3002W) for installing the lights in the cups and tea pot. These are the smallest lights that put out a reasonable wattage. I want to use [silver crown bulbs like this](http://www.grandbrass.com/SearchShowItem.cfm?ItemNumber=BUCG16S40). **If** I can drill the holes I think the rest of the project will be relatively staight forward. ---
**Author:** ![AaronX](https://avatars.discourse-cdn.com/v4/letter/a/7bcc69/32.png) [@AaronX](https://boards.straightdope.com/u/AaronX)\ **Post date:** [June 12, 2013, 7:59am UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/6 "2013-06-12T07:59:48Z")
Are you planning to make something like this? [https://lh6.googleusercontent.com/-A2eOfpH-Pac/UOOgGiJILSI/AAAAAAABHkU/q3mDb5wm2WY/s640/IMG\_0552.JPG](https://lh6.googleusercontent.com/-A2eOfpH-Pac/UOOgGiJILSI/AAAAAAABHkU/q3mDb5wm2WY/s640/IMG_0552.JPG) ---
**Author:** ![aNewLeaf](https://avatars.discourse-cdn.com/v4/letter/a/ac91a4/32.png) [@aNewLeaf](https://boards.straightdope.com/u/aNewLeaf)\ **Post date:** [June 12, 2013, 10:18am UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/7 "2013-06-12T10:18:26Z")
Do you have to drill it? Would a torch work? ---
**Author:** ![Deeg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/deeg/32/2955_2.png) [@Deeg](https://boards.straightdope.com/u/Deeg)\ **Post date:** [June 12, 2013, 4:28pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/8 "2013-06-12T16:28:31Z")
> [@AaronX](#): > > Are you planning to make something like this? [https://lh6.googleusercontent.com/-A2eOfpH-Pac/UOOgGiJILSI/AAAAAAABHkU/q3mDb5wm2WY/s640/IMG\_0552.JPG](https://lh6.googleusercontent.com/-A2eOfpH-Pac/UOOgGiJILSI/AAAAAAABHkU/q3mDb5wm2WY/s640/IMG_0552.JPG) That’s close but my cups will will hang from the base by a wire. > [@aNewLeaf](#): > > Do you have to drill it? Would a torch work? I have an oxy-acy torch. Is that easier? It seems like that would be harder to control. ---
**Author:** ![Roderick\_Femm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/roderick_femm/32/14875_2.png) [@Roderick\_Femm](https://boards.straightdope.com/u/Roderick_Femm)\ **Post date:** [June 13, 2013, 9:44pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/9 "2013-06-13T21:44:00Z")
If I may piggyback on this thread with a question of my own: I wanted to have a towel bar installed on the outside of my shower door (this requires drilling two holes so the bar can be anchored on the inside), which was already tempered, but the provider said it was not possible to drill through it after it had been tempered (they do their customization first and then temper the glass). Is this not true? The door is pretty thick, maybe 3/4", maybe that makes a difference? Roddy ---
**Author:** ![purplehorseshoe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/purplehorseshoe/32/2996_2.png) [@purplehorseshoe](https://boards.straightdope.com/u/purplehorseshoe)\ **Post date:** [June 13, 2013, 10:45pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/10 "2013-06-13T22:45:44Z")
I’m fairly certain that you can neither cut nor drill glass once it’s been tempered - to do so would cause it to shatter no matter what. That said, I want what’s in the link from **AaronX**! WANT! ---
**Author:** ![purplehorseshoe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/purplehorseshoe/32/2996_2.png) [@purplehorseshoe](https://boards.straightdope.com/u/purplehorseshoe)\ **Post date:** [June 13, 2013, 10:47pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/11 "2013-06-13T22:47:36Z")
Oh, here, I’ll just let [wikipedia](http://en.wikipedia.org/wiki/Toughened_glass)explain it better: > [@](#): > > Any cutting or grinding must be done prior to tempering. Cutting, grinding, sharp impacts and sometimes even scratches after tempering will cause the glass to fracture. . . Toughened glass must be cut to size or pressed to shape before toughening and cannot be re-worked once toughened. Polishing the edges or drilling holes in the glass is carried out before the toughening process starts. ---
**Author:** ![picunurse](https://avatars.discourse-cdn.com/v4/letter/p/7bcc69/32.png) [@picunurse](https://boards.straightdope.com/u/picunurse)\ **Post date:** [June 13, 2013, 11:33pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/12 "2013-06-13T23:33:19Z")
This! Been there tried to do that. I was cleaning up glass pebbles for days. I was luckily wearing eye protection and long sleeves, since the glass exploded. I actually had some bruises and one small cut. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [June 14, 2013, 12:02am UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/13 "2013-06-14T00:02:41Z")
**Deeg** , you only need a hole large enough to pass the wires through. You can glue the socket to the interior. ---
**Author:** ![the\_O](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@the\_O](https://boards.straightdope.com/u/the_O)\ **Post date:** [June 14, 2013, 2:30am UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/14 "2013-06-14T02:30:35Z")
I used to do stained glass. To cut such a hole out, I’d first drill an 1/8 pilot hole. To do that, I’d make a circle out of plumber’s putty and fill that with water; my pilot hole mark would be surrounded by water as I drilled my hole . I have what is known as a “ring saw.” This is a specialized form of \*\*\*wet \*\*\*\*bandsaw \*that is made for glass art. I’d thread my ring saw blade (the blade comes apart) thru my pilot hole and cut my circle out. It’s easy with the right tools. ---
**Author:** ![Deeg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/deeg/32/2955_2.png) [@Deeg](https://boards.straightdope.com/u/Deeg)\ **Post date:** [June 18, 2013, 9:57pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/15 "2013-06-18T21:57:24Z")
What do you guys think about using something like this? > **[Glass-Holes.com is for sale | HugeDomains](https://www.hugedomains.com/domain_profile.cfm?d=glass-holes.com)** > > This domain name is available, own it today. Affordable payment options. Fast and professional service. (ETA: any web site called [glass-holes.com](http://glass-holes.com) has gotta be good, right?) ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [June 18, 2013, 10:02pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/16 "2013-06-18T22:02:58Z")
> [@Deeg](#): > > What do you guys think about using something like this? > > [http://www.glass-holes.com/1-1-8-Glass-Cutting-Holesaw-dhs118.htm](http://www.glass-holes.com/1-1-8-Glass-Cutting-Holesaw-dhs118.htm) > > (ETA: any web site called [glass-holes.com](http://glass-holes.com) has gotta be good, right?) That is the correct tool. You need to flood it with coolant while you are cutting the hole, and it will be really messy. Also, a drill press will pretty much be required. If you don’t use a battery-powered drill, be sure to use a GFI-protected circuit! ---
**Author:** ![Deeg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/deeg/32/2955_2.png) [@Deeg](https://boards.straightdope.com/u/Deeg)\ **Post date:** [August 14, 2013, 7:25pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/17 "2013-08-14T19:25:06Z")
Minor zombie alert! Thought I’d post a follow-up. I ended up getting a drill bit from [these guys](http://www.diamond-drill-bit-and-tool.com/Diamond-Drill/Diamond-Drill-Bits.shtml). It was more expensive than the $5 bits on Amazon but I figured, perhaps wrongly, that I was getting what I paid for. I’ve used it on a single glass teacup so far and it worked great. A nice clean hole 1-1/8" wide and it was relatively simple. I kept the bit under water the whole time and went slow. ---
**Author:** ![jasg](https://avatars.discourse-cdn.com/v4/letter/j/f0a364/32.png) [@jasg](https://boards.straightdope.com/u/jasg)\ **Post date:** [August 14, 2013, 8:54pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/18 "2013-08-14T20:54:29Z")
For searchers who get a hit on the title of this thread, your drill supplier has a FAQ [page](http://www.diamond-drill-bit-and-tool.com/Diamond-Drill/How-To-Drill-Tile-Glass-Stone.shtml#Drilling%20Tempered%20Glass) on drilling tempered glass. Short answer - don’t try. ---
**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\ **Post date:** [August 14, 2013, 11:51pm UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/19 "2013-08-14T23:51:41Z")
Question: I have a beautiful tequila bottle (with a blown glass interior sculpture). I would like to convert it to a lamp (need a small hole drilled in the base). Should I bring it to a glass shop? Drilling sounds dicey-I have never done it before. ---
**Author:** ![\_Olive](https://avatars.discourse-cdn.com/v4/letter/_/4af34b/32.png) [@\_Olive](https://boards.straightdope.com/u/_Olive)\ **Post date:** [August 15, 2013, 7:08am UTC](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761/20 "2013-08-15T07:08:10Z")
I have a friend who would buy glass vessels to use as flower pots. After trying many times to drill a hole in the bottoms of these different vessels without success, he took a chisel and hammer and made his holes without breaking the glass. They are not uniform but it works most times. This discovery was 20some years ago and we both still use this method. [Next page](https://boards.straightdope.com/t/tell-me-the-best-way-to-cut-holes-in-tempered-glass/660761.md?page=2)