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There are lots of ways to do this particular trick. You may have seen bottles “cut” using a bucket of ice water, a string soaked in fuel and set alight, a hot narrow gauge resistive wire, or some combination of the above. I’ve tried all of these ways, at one point or another, with varying degrees of success, and I’m reporting here the method that gives most consistent results for me. But if you’re interested in trying some other way, by all means experiment. Glass bottles are freely available just about everywhere, and you can always recycle your mistakes.

Regardless of which of these methods you favor, “bottle cutting” is generally a misnomer, as what’s really going on is a process of controlled breakage. (Unless, of course, you’re actually using a tile saw or something similar, in which case I’m prepared to agree it’s really “cutting.”)

Anyway. Glass, molecularly, is mostly silicon dioxide, but it’s distinct from crystalline solids like ice or table salt in that the molecules are not well-ordered in space. You may have heard some balderdash about how glass is really a liquid with practically infinite viscosity; generally the swelling of ancient cathedral windows at the bottom is sited as evidence to that effect. Well, it’s not true: There is, to my knowledge, no reliable evidence that glass will flow at room temperature regardless of how long you wait. Turns out cathedral glaziers made their windows thicker at the bottom on purpose.

But as an analogy, “infinitely viscous liquid” is not a bad way to understand the random molecular ordering of bulk glass. The upshot of this anisotropy is that glass does not cleave in orderly ways: Cracks tend to wander off in random, unpredictable directions, and shattering can easily occur due to internal stresses. There is, therefor, an element of luck involved in the bottle cutting operation, but with a bit of practice and good technique you can make it work most of the time.

Tools

  • Glass cutting wheel
  • Bottle cutting jig
  • Small butane torch
  • “Lazy Susan” or other rotating platform
  • Scrap of plate glass at least 8×8″

Materials

  • A suitable glass bottle to cut
  • 400 grit silicon carbide wet/dry sandpaper
  • Bulk silicon carbide grit (at least 80 mesh)
  • Tap water
  • Oil for glass cutting wheel

Step 1: Select a bottle

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Your choice of bottle depends on what you want to do with the finished piece. Are you making a drinking vessel? A flower pot? A lampshade? Very often people are interested in cutting a particular bottle that has unique aesthetic or sentimental appeal. A special bottle of booze or wine, well-cut to make a useful container, can make a great gift for the person you shared it with. Before you attempt to cut a valuable bottle, however, you should develop skill with bottles that are disposable to you. You will almost certainly ruin a few getting the hang of the process.


Step 2: Score the bottle

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It is important that the bottle be scored cleanly and evenly in a circle around its circumference. Inexpensive jigs are available commercially for this purpose. Get a quality metal one, or build one yourself, and steer away from plastic jigs hyped on late-night TV and the like.

The cutting jig is first set to accurately position the cut along the length of the bottle. Then a drop of cutting oil is applied to the built-in glasscutting wheel. Now, set the bottle in place and apply firm pressure towards the cutting wheel as you rotate about the bottle’s axis. Maintain continuous pressure as you rotate, and stop as soon as the scoreline comes all the way ’round and meets itself. Resist the temptation to go over the same scoreline more than once. This will only lead to a messy break.


Step 3: Apply heat

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Position the bottle upright in the center of your turntable. Spin it around a few times to make sure the bottle is well-centered, then fire up your torch. Direct the flame just slightly above the scoreline, about four inches away, and steadily rotate the turntable with your free hand. The rotation doesn’t have to be very fast, but it should be constant and even. The goal, obviously, is to evenly heat the bottle around the scoreline. Uneven heating, again, can lead to cracks wandering off in all directions.

You will hear a series of clicks and pops as the bottle breaks. You can also, generally, see the break as it propagates around the glass. Continue rotating and applying heat until the break is complete, removing the flame and testing occasionally by lifting the bottle from its neck. When the cut is complete, the top of the bottle will lift off with no effort. Be patient at all times. Nothing in this process can be forced.


Step 4: Polish the edge

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step04b.jpg

If everything went well, you now have one or more bottle sections with relatively clean breaks along their edges. Some small deflection, especially where the beginning and end of the scoreline meet, is common and can be polished out. Bumps or jogs much larger than 1mm, however, become increasingly tedious to grind away, although it can be done if you’re persistent. It’s generally much faster to just cut another bottle than to try to repair a fracture gone awry.

The edge is polished by lapping against a piece of scrap plate glass. This can be window glass, a bit of mirror, or, as in my case, the plate from an old broken scanner. Dump a pinch of grit into the center of the lapping glass and wet it with a spray bottle. Then set the bottle section edge-down against the abrasive surface and, applying light pressure, scrub it around in a figure-eight motion. Be aware that the sound this makes can set your teeth on edge, if you’re sensitive, so you may want to have ear protection around just for the sake of aesthetics. But it’s not generally loud enough to be dangerous.

Continue lapping, adding grit and/or water to the slurry as necessary, until the edge is completely polished. Unfortunately wetting can make this difficult to tell, so keep at it until it feels done, then wipe off the edge with a paper towel until it’s completely dry. Now, it should be easy to tell if you need to polish some more or not: The edge should be smoothly and uniformly “etched” all over, with no glossy spots remaining.


Step 5: Round over the corners

step05.jpg

The lapping process will produce a very flat edge which, where it intersects with the sides of the bottle, can make for a fairly sharp corner in cross-section. Particularly if you want to use the cut bottle as a drinking vessel, I recommend that you take a minute to lightly break the inner and outer corners with a scrap of silicon carbide sandpaper. The easiest way to test this process is by touch: Continue until the corner feels comfortably smooth to a fingertip run around the edge.


Notes and ideas

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I have found that the use of a turntable during the heating process makes a significant difference. Attempting to manually rotate the bottle never works so well for me, but if I use a turntable the breaking process is quite reliable. The turntable I use is the bottom part of a cheap plastic rotating shelf intended to keep spices in the kitchen cupboard.

If you want a neater polished edge, you can use a series of grits of increasing fineness to do the lapping. A recharge kit for a rock polisher can be a good source for these. If you want to go this way, proceed (obviously), from larger to smaller grit, clean the edge thoroughly between steps, and be certain to use a separate lapping plate for each grit. Contamination of finer with larger grits can spoil the polishing effect.

The physical details of the bottle you choose to cut can also make a big difference. Generally, straight-sided bottles are easier to score evenly than those with round or sloping sides, so you may want to limit yourself to those at first. Many bottles have features I call “useful inclusions,” which are rings or grooves molded in around the bottle’s circumference. These are handy for two reasons: 1) Siting a cut at such an inclusion generally results in a better-looking finished piece, and 2) the inclusion itself can be used to guide a manual glasscutting wheel, eliminating the need for a bottle-cutting jig.

How the bottle is labeled can be important. I personally prefer bottles with painted-on labels, like Corona bottles, because the markings will stand up to wear, water, and washing over time and will continue to show off the origins of the piece throughout its lifetime. Or you can simply remove the labels altogether. Paper labels are generally the toughest to clean off; and the best tool I’ve found for this process is the wire wheel on a bench grinder. Even so, you may have to wipe off the remaining glue using Goo-Gone and/or lighter fluid.

If you plan to etch your bottle in some way, it is possible to use the label as a built-in resist. Just cut the design you want etched into the label, peel off the positive areas, and apply etching cream as usual. Adhesive plastic labels work best for this process; paper ones will result in messy edges where the etching cream bleeds under. When the etch is complete, just remove the remaining label as you normally would.

Sean Michael Ragan

I am descended from 5,000 generations of tool-using primates. Also, I went to college and stuff. I write for MAKE, serve as Technical Editor for MAKE magazine, and develop original DIY content for Make: Projects.


Related

Comments

  1. keith royster says:

    Great article! As many homebrewers may tell you (because they frequently reuse commercial bottles to bottle their beer), one of the easiest ways to remove bottle labels is to soak them in a diluted solution of ammonia, water, and (optionally) dish soap. Most label glues are ammonia-soluble, and the dish soap will help the solution penetrate the label. Soak them for a few hours and many times the labels will practically float off as you remove them from the soak tank.

    1. Joel says:

      only we use hot water and bleach to soak the bottles. One of those plastic scrapers for cleaning dishes works well to scrape off any glue that stays on. Stay away from labels that are fully glued over the whole surface and look for ones that are only glued at the ends of the label.

  2. alandove says:

    Dishwasher detergent, aka washing soda, also works very well for removing bottle labels. Soak the bottle(s) for a few hours in a bucket of water with a liberal sprinkling of Cascade, and the labels will usually fall off.

  3. Neil says:

    I have found that for adhesive labels, common on wine bottles, the bottle can be heated for 10 minutes in a 200-250 degree oven to soften the adhesive, and after that a scraper can be used carefully to remove the label. The label can be saved on a piece of wax / cooking parchment paper. Use good potholders / gloves and be careful please.

    For the glue on wine bottle labels, soaking in warm soapy water as user alandove suggested has worked well for me too.

  4. nameless says:

    why don’t you just heat it up until it melts – surface tension of the melted glass will produce a rounded, lip-friendly drinking surface without the tedious grinding. That’s how purchased glasses get that smooth, round edge.

    1. Anonymous says:

      This is unlikely to work safely or successfully, as the thermal differential between the edge (as you heat it with a torch) and the rest of the vessel will be enough to burst the vessel. Been there, done that :)

  5. derek says:

    TSP soak to remove lables.

  6. Matt Mets says:

    Oooh! I wonder how much work it would take to fashion a bunch of acoustically tuned bottles to make a set of glass bells?

  7. Michael W. says:

    A couple of hints.

    Don’t heat the edges to smooth them. Yes, glassblowers do use torches to smooth edges of glasses sometimes, but we do it before we put them in the ovens to cool down. The glass is already hot and the temp. difference is not enough to cause problems. Wine, beer, mineral water glasses are not made of borosilicate glass!

    A small portable record player works great for use as a turntable. My wife cut hundreds (thousands?) of glasses that way. It frees up both your hands to steady the torch and gives a consistent speed.

    1. Dana D. says:

      What technique did your wife use to polish the edges of the bottles? Hand-sanding leaves a gritty-looking edge.

  8. don says:

    What sort of cutter and jig are you using? I have a hand made jig but it really isn’t as adjustable as I want. Can you link to the cutter and jig if possible?

  9. adam says:

    Hi. Yes i also wonder what kind of “Bottle cutting jig” you are using and how i can obtain one.

    i do own a basic glass cutter(metal handle) but i have never heard of a bottle cutting jig and i have never seen one anywhere.

    1. dom says:

      To both Adam and Don, I clamp a regular glass cutter in a wooden wood clamp near the tip of the wood jaws so that the glass cutter is horizontal. Then I use a bar clamp to clamp that wood clamp to my work bench, using scrap pieces of 3/4 and 1/8 in. thick wood as flat shims to raise the cutter tip to the desired height. Then I press the bottom of the bottle or jar flat on the work bench and rotate the vertical bottle or jar against the cutter tip.

      So that solves the problem of not having a bottle cutting jig, but only if you have wood and bar clamps along with scrap pieces of wood!

  10. Ren says:

    Definitely going to try this asap.

    Perhaps the bottle tops can be used as glass funnels, as well. Waste not, you know.

    1. graceful says:

      I saw a really great Heineken bottle neck. It was cut on an angle and a bottle opener was fitted into the hollow of the neck.

  11. Steve Matliss says:

    It’s possible to split the bottle after scoring using a “hammer” made from a bent piece of heavy wire instead of a blowtorch. You tap the _inside_ of the bottle just above the score line all the way round. You can tell where the glass is separating as the score will look glossy or mirrorlike at that point. Then keep tapping around the bottle until the split goes all the way around at which point the top lifts off. It helps if a small rubber ball or something similar is threaded onto the hammer. The ball sits in the neck of the bottle and keeps the hammer tapping in the right place.

  12. Anonymous says:

    when I was a kid, I remember my grandparents doing this to make glasses, and they would use the necks as candle holders/carriers.

  13. Jean says:

    Just to add my two cents: an easier method to remove labels is as follows:
    1) rip the label off without caring about glue residues
    2) remove glue with a cloth soaked in olive oil or some other kind of cooking oil
    3) remove oil with dish soap

  14. Jim Rudkin says:

    You can always finish the neck and use UV glue to glue it to the bottom of the bottle to make footed goblets.

  15. Pittsburgh Vince says:

    Sorry, but you are wrong about glass flowing over time, at least in the case of laboratory glass over a long period of time.

    In high school I had an ancient chemistry teacher named Robely Jump Hackett who was the stuff of eccentric legend. He had a room off the front of the classroom where he kept his supplies.

    On top of the high built-in cabinets there he had a collection of very old hand-blown flasks, beakers and pipes. Nearly every one had been oddly and severely bent down or over under the influence of gravity during a time of well over forty years. A beaker’s side had bulged slightly, leaving the mouth no longer horizontal. The neck of a globe flask had partly collapsed and tilted over like a chimney falling in slow motion. Tubes that had been left connected sagged like strands of spaghetti between two plates.

    Our school had no air conditioning and was always quite warm in spite of the high ceilings. There was no evidence that the glass pieces had been caught in a fire. I took the obvious distortion of this long-disused equipment to show that lab glass is a supercooled liquid rather than a crystalline material.

    1. Sean Michael Ragan says:

      …to see a published study of this phenomenon, but I don’t know of one. I find it unlikely that borosilicate glass would droop noticeably over that short a period of time, under warm or hot atmospheric conditions. If that were so, you would expect the phenomenon to be commonly known and widely observed among truly ancient pieces of glass, and in fact it is not. Windows in warm areas of the world would not last more than a century.

      1. Lisa Jenni says:

        When I was at college back in Munich/Germany, I was in a class for Glass Technique. The teacher explained the speciality of Glass being technically a “liquid”, but it’s hard to see for human beings, because of the enormous timespan until it’s actually visible.
        But, there is proof for it: The windows of the Dome of the city of Augsburg. These artisan glass windows have been in place continuously for 1000 years, and they are measurable thicker (note: the windows have only been temporarily removed for safe storage during WWII).

        Maybe you have some interesting travels on your bucket list?
        Lisa

  16. Steph Ay Knee Why says:

    what if i wanted to keep the label on the bottle?

    1. Sean Michael Ragan says:

      I kept the label on mine! It still looks just like it did in the photos above. Just have to be careful not to burn it with the torch.

  17. LeeAnn Horan says:

    Where did you find your cutting wheel? None of the ones I can find online look like this.

    Thanks for the tutorial!

  18. LeeAnn Horan says:

    Where did you find the cutting wheel used? None of the ones I can find online look like this.

    1. Hi LeeAnn-

      I bought it almost a decade ago, now, online, and sadly don’t remember where nor have any surviving record thereof. Wish I could be more helpful. Thanks for reading, and thanks for commenting.

      -SMR

      1. Nathan Plant says:

        Google “Ephram’s Bottle Works” for the jig.  I just bought one, and it’s super easy to use.

        Edit: Oops. I meant to reply to LeeAnn.

  19. Mark Henry says:

    Hello.
    This is the most beautiful cut bottle glass I have ever seen. I have bought a cutting wheel. I would definitely try this at home. Thanks!
    _
    industrial equipment

  20. Mark Henry says:

    Hello.
    This is the most beautiful cut bottle glass I have ever seen. I have bought a cutting wheel. I would definitely try this at home. Thanks!
    _
    industrial equipment

  21. Anonymous says:

    Very helpful article!
    Paper labels can be attached with water-soluble glue or nonwater-soluble glue.
    Water-soluble I just soak in water and scrub off with a mesh kitchen scrubber.
    Non-water-soluble might peel off if the bottle is filled with HOT water and let sit until the label is warmed. 
    I have found WD-40 removes labels, too.

  22. Anonymous says:

    great ideas!!!
    does anyone know how to cut a beer bottle vertically? I saw a night lite done like this and would like to replicate it.

  23. Mr. Karl says:

    Can this technique be used to cut the bottom off a cut crystal decanter?

    1. Sean Ragan says:

      I don’t know. I can tell you that this technique takes some practice, and you can expect to ruin a few bottles before you get the hang of it. I would hesitate to try it on a nice piece of glassware unless you have spares around to experiment with.

  24. RW says:

    This is AWESOME and exactly what I was looking for! Thanks for taking the time to post this.

    Can’t wait to try it!

  25. Johnny Dinkelmann says:

    I just bought a bottle cutter here in Berlin for a project for around 30 USD in a shop, but noticed that there are in fact many different kinds of cutters for sale on amazon, and for a fair price as well:

    cutters on Amazon

  26. Titus says:

    Ponce you score a cut with the diamond cutter round the glass bottle , I have found that just dipping it in boiling hot water for a minute and then in ice cold water helps in getting a clean cut , haven’t tried the polishing with the grit though , can’t wait to do that as you mentioned , thank you for your suggestions though ! :)))
    Regards
    Titus

  27. You are so interesting! I do not believe I’ve read anything
    like that before. So good to find somebody with some genuine
    thoughts on this issue. Seriously.. thank you for starting this up.

    This site is one thing that’s needed on the web, someone with some originality!

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