It's interesting to know that you can make a glass from a bottle, engraving a cut all around the circumference and splitting it in two with a few tricks. If you plan to make many glasses and if you wish to obtain a perfect flat cut, you can preferably build your own cutting device.
The main advantage of using a jig like this one, is that you can obtain a perfectly flat cut very simple to refine with sandpaper (see image). 
I will explain here how to make the jig from common and cheap objects.

Step 1: The Sketch

After measuring some bottles, I planned to leave about 12 cm between supports, with the possibility to increase this distance to 17 cm. This is enough to cut the standard little beer bottles and also the 1 liter ones.
My design is very simple. my intent was to build a jointed arm which could also shift along the axial direction, and sturdy enough to maintain the position while you push the cutting blade into the glass.
So I decided to use what I already had in my house, and the device took gradually shape.

Step 2: The Components

The wood base is a salami cutter board about 14 x 25 cm, so it's perfect for my project. The other main parts are, other than the essential cutting blade, four furniture wheels, a piece of electrical conduit and some wood beams.
The wheels diameter has to be not more than 4 cm, and it should be cool find wheels with a rubber surface.
The wood beams are:
  • one piece about 25 x 4 x 2 cm (length, high, width)
  • one piece 11 x 4 x 2 cm
  • about 25 cm total length of a 1 x 2 cm section beam
The conduit is wide and long the same as the bigger beam (25 cm long and 2 cm wide in my case) and it has to be the type with a detachable cover.
Then you need only some glue, different types of screws, a bolt and four rubber feet.

Step 3: First Holes

All the holes on this device are made by hand, but you could better use a column drill to obtain perfect perpendicularity.
I added a new hole in the bottom part of the wire conduit, so a total of three holes cover the full length, but you can also add two more holes, since they will hang better the "rail" on the wood board.
Then I also made four little holes in the top cover, which is 8 cm long. These holes are not centered on the shorter side, to avoid interference between horizontal and vertical screws.

Step 4: Let's Make the Joint...

A pair of long screws acts as joint of the wood arm. So cut a couple of wood pieces 3 x 2 x 1 cm and, about 7 mm from the border, drill an hole in the direction of the longer axis. Dispose the pieces on a flat surface, and mark the holes position from the conduit cover. Then drill the four holes for the screws.

Step 5: ...and the Arm

Let's refine the arm head so that it could keep handy the cutter. I tried to use the cutter as it is, avoiding to drill it. A big screw keeps it steady into a groove engraved in the wood. Since I made some upgrades to improve the operation of the tool, I also replaced the screw with a bolt, and I tilted more the cutter, as you can see in the first picture of the next step.

Step 6: Let's Assemble the Cutter Mechanism

My first attempt was to screw the two little wood blocks directly on the conduit cover. This doesn't work, because the two-parts pivot (the two long horizontal screws) has more play than a single pivot, the plastic cover isn't rigid enough, and the arm was not very steady. So I added an additional wood beam to reinforce the device.
After screwing the horizontal pieces together insert the arm and insert the long screws in the holes so to mark the position where to drill the hole in the arm.

Step 7: Glue the Beams

Place the "rail" over the bigger wood beam and mark the positions of the holes. Drill the holes but wait to glue the pieces to screw the rail in.
Put two wheels on the board to have the exact position where to glue the big beam. I used two-elements glue to be faster, but you can also use normal wood-glue.

Step 8: The Rollers

Meanwhile the longer beam fastens you can drill the holes for the rollers. I used very short screws so they don't stick out the bottom surface of the board. The last two rows of holes are to shift two wheels so that a larger bottle could be held.

Step 9: Rail and Rubber Feet

Now assemble all the four wheels, screw the rail in place, add four rubber feet, clean the surfaces... the main piece is almost ready.

Step 10: Some Finishing

Since the trolley cover moves loosely along the rail I decided to glue two nylon stripes inside the longer edges. I've cut the stripes from a nylon cake tray. You can also smooth them with sand-paper.
Use cyanoacrylate glue, and to be sure the stripes are kept pressed during the drying, apply the cover on the rail as soon as applied the glue.
This solution works great, and you can set up the resistance of the movement simply moving fast the "trolley" to and fro, since the heat will consume a bit the plastic, mitigating the opposition force.

Step 11: The Bottle Stop

Glue the last wood beam so that it will act as stop for the bottle. Check that it's high enough to reach also the biggest bottles. This beam will also act as bracing for the rail, so add some glue between the two boards.

Step 12: Test It!

Time to try the device. I engrave a big Barbera bottle, and a smaller Birra Moretti one (both typical Italian drinks).
Unfortunately there were a couple of mistakes in my design:
  1. as I explained before the arm joint was not very sturdy
  2. the cutter's blade wasn't reaching the glass of biggest bottle, because the steel frame touched at first
  3. blade route was a bit misaligned with the circumference, and it drifted out of it

Step 13: Solve Issues

Solving the issues was not hard:
  1. I added the 8 cm wood beam between conduit cover and wood blocks, that makes the joint stronger
  2. I re-designed the arm with a tilted groove 
  3. I filed the groove surface with more attention to alignment, and I added a more reliable bolt as connection for the blade
These improvements are already included in the previous steps, but you can see more detailed pictures of the arm here.

Step 14: What's Missing?

Glasses? Yeah, you're right... since I'm not very skilled in this technique, despite the perfect groove, I've broken all the bottles I've at home!
You've to wait some time, that I'll drink more beers and I'll try again... meanwhile you can look the many good step-to-step and video instructables about this same topic

Step 15: I Did It!! [UPDATE]

Finally I did it! After engraving a SINGLE cut around all the circumference I rotated the bottle over the little burner, after half minute I paused ten seconds, then I let some drops of cold water fall over the cut, and I heard the crick, I put the bottle over the flame again and it split!
Anyway, there is enough space between the two sets of wheels to contain a common tea light, so that you can heat the bottle spinning it on the same gear. I will try that solution next time.
With medium and fine-grained sandpaper I refined the border sanding it on a flat surface and removing the sharp edges. After that it appears awesome! ...yes, this is a tiny cup for coffee, nothing special... but it's funny anyway!

Step 16: Last Improvement [UPDATE]

To obtain a perfect cut, I had to change the wood arm into a sturdier metal brace, and with the use of a column drill I built a new carriage with perfectly aligned joint. I was so lucky that I found in my junk that metal U profile with perfect length and with already the four holes! :-)
I had to smooth out the wood edges under the arm to let it moving. In addition this carriage is higher than the first one, so that I can cut bigger bottles with less bending of the blade, and pushing it from above and not from the side.

Step 17: The End?

This new solution works very good, since the joint is made by a single steel bar passing through all the length, and you can lock the blade on the arm without worrying about the wood deformation.
When you push the blade against the glass it remains exactly on the circumference, and at the end of the rotation you'll hit the start point of the trace, this is essential to make perfect splitting.
Since I've a good spring which fits well on the side of the arm, I'm planning to add it so that the arm will lift when you release the pressure, that will be cool... stay tuned ;-)
Hi!! Great Instructable. Made some mods though. The cutter is fixed and the back of the bottle is what I move depending what I want. Still have to cut a bottle though. Hahaha, very fun to do and hope it works. Thanks.
<p>Great idea. I had struggled to come up with a way to hold the cutting wheel properly. That is brilliant. Thank you!</p>
<p>I loved what you did to fix the Diamond haha very clever!!</p>
<p>I made it but is hard to crack the glass with a candle.</p>
<p>just sketched this exact design, glad to see someone already improved on it thru troubleshooting,. thanks for sharing. </p>
Where did you find the wheels?
<p>I think any hardware store, or Any Target shop you can find similar wheels</p>
<p>I think any hardware store, or Any Target shop you can find similar wheels</p>
<p>I think any hardware store, or Any Target shop you can find similar wheels</p>
<p>How do you apply heat to get than nice result? I get some nasty cracks pretty often.</p>
<p>Today i will start fabricating it cz i like the way it looks and functions.</p><p>once done i will try to add a heating resistance wire and come metal in the place between the wheels.</p><p>I will keep you guys updated and try to take some photos of the result</p>
<p>I am disapointed that only pro can download</p>
<p>a very elegant design, thanks for sharing!</p>
<p>Good idea</p>
<p>Muy bueno... gracias por el aporte!</p>
<p>As I love building fun new tools, This one is really cool and bet it works great as well. There are other cool ways to cut glass as well. Glass is very brittle with hot and cold temps. Take a bottle between boiling water and ice water and it will cut too/ </p>
<p> I have made a few bottle cutters over the years, this one is by far the nicest design ive seen.</p>
<p>Hat off...</p>
I made something like this 30 years ago and used a piece of nichrome wire to heat the score made with the glass cutter,popped apart very easily.Never broke a glass.If you try this make sure to wear eye protection in case it should pop off small glass chips.It did this on some of the bottles I did but not all of them.Made about 6 sets of 12 glasses and gave as Christmas gifts,people never saw this before and really liked them.
Do you mean that you hooked up a nichrome wire to a standard power outlet? Did it work?
<p>Oh NO! LOL That would be an explosive mistake. I use a variable DC power supply, but not everyone will have one. I have used an old computer power supply and a custom circuit but that was way more complex than it was worth. I eventually gave up on using nichrome because it was more effort (and risky) than using the hot water stress method.</p>
How did you heat the wire? That's interesting...
I used a transformer,it was a long time ago but I think it was 36v.I got the nichrome from work where it used to heat parts prior to being pressed over another sleeve that was frozen to make it smaller.
<p>Nicely done. One thing you might consider: Use a rubber band to create light but consistent pressure on the blade. In your design it looks like you could add a small hook on the frame, then attach the rubber band from the blade to the hook. Finding a rubber band with the right tension per bottle diameter may be tricky though. However gaining consistent pressure, plus having two hands available to turn the bottle may help improve your cuts. I had gone to a tile saw for consistent cuts, but your instructable has inspired me to give this method another try. </p>
<p>very nicely done and great images to explain the whole procedure!!!! Great! </p>
<p>Very Good Well Shown.</p>
<p>Great guide, thank you :)</p>
<p>Excellent instruction and clear, clean design. Only question is how did you find out about the heat and water to complete the cut???? I saw one guy at a craft show put baking soda and vinegar in then capping the bottle to break it clean.... too messy for me. </p>
<p>Thanks for the guide! I have the same glass cutter, how did u remove the wooden handle of the glass cutter?</p>
I just take a piece of twine soak it in a little rubbing alcohol tie it around the bottle where I've run the glass cutter touch a flame to it and it will pop in half works for every size bottle or jug I've tried it on
<p>Do you have a link to where you got the wheels you used please?</p>
<p>Nicely done. Thanks for this.</p>
very cool... I had a hard time using &quot;commercial&quot; versions and ended up using a wet tile saw for my best results....
Great idea, congratulations..
This is incredibly clever and beautiful! I want one :D
thanks Jessy, I've already offered this gear to a person, but next one is for you ;-)
with rollers so cheap..this is a brilliant design. Applaude.
yes, they're about 2&euro; each here in Milan
wawoo..in Asia u buy a set of 4 for 2EURO...great luck
I held a glass cutter at a given height by pressing it down hard on the tail of my vice)sat the bottle upright, then pressed the kerosene lubricated wheel into the bottle and rotated it 360 degrees. Height can be adjusted by wood blocks under the cutter or bottle bottom. I used a bent giant nail (landscaping nail, about 12&quot; long with a bend at the &quot;head&quot; end of about 60 degrees). I inserted it into the neck of the bottle and tapped gently and patiently from the inside of the bottle along the score line until the crack propagated. The longest part of the job is the &quot;polishing&quot; of the edge. I use a flat diamond sharpener, like those used to sharpen knives and available at &quot;harbor freight tools&quot; etc. This sharpener also works to fix small chips in the rims of fine crystal glasses making them like new! Great work! Thank you!
that's an unusual way, but it seems effective, thanks!
I made a very similar jig for cutting bottles but I was a little lazy and instead of using a glass cutter, I use the jig (without the glass cutter) on my wet saw that I use for cutting ceramic tile. It even has the same type of wheels. I just put the jig on the sliding bed and use the diamond blade to cut the glass while I rotate the bottle on the wheels. I can get different lengths of cuts by positioning the jig on the tile saw sliding bed. I used it to make the windows for my Hobbit House that houses my fish tank in my Aquaponics system. Nice Instructable!
Mmmm! Moretti La Rossa! Need more emptied? I'll help!
I held a glass cutter at a given height (I actually used the tail of my vice)sat the bottle upright, then pressed the kerosene lubricated wheel into the bottle and rotated it 360 degrees. I used a bent giant nail (landscaping nail, about 12&quot; long with a bend at the &quot;head&quot; end of about 60 degrees). I inserted it into the neck of the bottle and tapped gently and patiently from the inside of the bottle along the score line until the crack propagated. The longest part of the job is the &quot;polishing&quot; of the edge. I use a flat diamond sharpener, like those used to sharpen knives and available at &quot;harbor freight tools&quot; etc. This sharpener also works to fix small chips in the rims of fine crystal glasses making them like new! Great work! Thank you!
Thanks Andrea; will have a use for this for an Instructable I'm planning. <br>I'm also a freelance engineer, that's what I will call myself now, sounds so much better than saying &quot; I'm a retired engineer but still doing some engineering stuff now and then.&quot;
That's right, Bill, engineer's mind never stops working ;-)
watch this: <a href="http://www.youtube.com/watch?v=sFXngPx3w3M" rel="nofollow">http://www.youtube.com/watch?v=sFXngPx3w3M</a><br> <br> you only have to score the glass and then use hot and cold water. touch it off with some fine grit sandpaper ...
here is a shortcut to the relevant 'score and heat with hot &amp; cold water'. clean edge in less than 2 minutes.<br> <br> <a href="http://youtu.be/sFXngPx3w3M?t=3m39s" rel="nofollow">http://youtu.be/sFXngPx3w3M?t=3m39s</a>
This is cool, but I've always gotten rough edges. Try this method instead. Works much better with less hassle: https://www.youtube.com/watch?v=E4yovEi7j7E

About This Instructable




Bio: I'm an Italian freelance structural engineer, graphic designer and photographer. I'm also investigating electronics, robotics and science in general. I enjoy hacking and ... More »
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