How to cut glass bottles

Here, in Bulgaria, we have really beautiful beer bottles, and I wanted to do something with them. I started a research on how to cut glass bottles and here are my results.

Spirits dipped rope

You know – get a string, dip it into some kind of a spirit, preferably lighter’s gas, tie it tightly to the bottle and light up. Wait for the flame to burn out and dip the bottle in cold water. Though this works, the resulting cut is edgy and a ton of sanding is required for it to look smooth and nice. Note, I didn’t even try this one.

Glass cutting jig

There are plenty of ways shown throughout the internet if you just type in “homemade glass cutter”. I tried some of those but with no good results. I wanted to cut just the bottoms of all my bottles. Every time the bottle slips, and the cut is crocked. Some jigs are a good idea, but required way too much stuff to buy. I ended up buying one “round bottle glass cutter” from amazon and it works extremely well… for round bottles.

Cold-Hot water dipping

When you make your scratch with the blade of the jig, you need to make the actual cut. You have to make the glass to expand and contract in order to crack it along the cut. The best way to do that is to warm up water, but not to a boil, just to simmer and run the cold water from the faucet.

scraching the bottle

First, rinse the bottle with the cold water and then carefully pour the hot water directly onto the cut. Repeat until you hear a crack and the bottom comes off.

rinsing the bottle

If you use boiling water, the glass will expand rapidly and it will cause it to break beyond the crack resulting in crocked cut. The same will occur if you put flame along the cut. The heat is just too much and makes the glass to distress.

failed attempt

failed attempt

As you can see there is much variation with the water temperature. For me it was a lot of trial and error and a lot of wasted bottles (good thing we are beer drinkers).

You can help yourself by using soldering iron. After making the scratch go along it with the iron.

soltering ircon along the cut

If yours is powerful you can even use only it. While going along the cut, frequently damp the bottle with water. Do this until you hear a crack or until the bottle is separated. My soldering iron is not that powerful so I use it to make the glass to crack where I need it to. Then I continue with the cold-hot water baths. If you don’t want any fancy tools this method is the best for you.

cut bottle

Then, wet-sand untill smooth, or untill you get bored 🙂

sanding the bottle

sanded bottle

Rotary tool

Ok, that was for the round beer bottles. Next, I wanted to cut Jack Daniel’s ones too. For them, I couldn’t use my jig as they are not round. So, I went and bought a dremel with tile cutting diamond wheel. But any rotary tool will do.
I first put painter’s tape on the bottle, and then marked where the cut should be.
I then had the water running from the kitchen sink faucet and started cutting, trying to keep the water to pass through the wheel at most times.

This takes some time and if you are impatient and push the wheel, it will chip bigger chunks from the inside side of the glass. The look is bearable but not the best, and requires a lot of sanding afterwards.

Also, I tried different speeds and the best results are with median speed and no pushing.

Finally, remember – safety first! Use protective glasses and long gloves while doing this as the glass dust causes a bad rash to your hands.