How To Cut A Bottle
Cut a bottle at your kitchen table and make unique recycled glass art!
Of the several ways to cut and separate bottle rings, the following method is fairly easy and inexpensive. You do not need a band saw (although it sure would be nice to have one!) to make vases, bells, bowls, glasses and more.
A good bottle cutter does not have to cost a lot. I like my Generation Green bottle cutter. It is very versatile, and easy to use. If you do not have a bottle cutter, you can use a pistol grip glass cutter, but you have to brace it. The goal is to score a straight, even line around the circumference of the perfectly clean bottle. If you are cutting the bottle by hand, make a wooden brace against which you can roll the bottle, or position the bottle upright and hold the cutter firmly on top of a sturdy object, like a soup can.
To cut a bottle, you turn the bottle, not the cutter. This way you will have an even score and a clean break.
Once your bottle is cut, you will need to run the line to separate the bottle. Many of the bottle cutters come with instructions, and some of those are a bit faulty. For example, the Generation Green recommends a boiling hot water bath followed by an icy cold water bath in repetitions. You can see how this would be problematic. Relying on intense thermal shock over such a wide surface area like that can result in the bottle cracking up the side instead of along your scored line.
Instead, heat the glass along the scored line with a candle flame or torch. Candles work very well. I typically set a pillar candle on top of a kitchen towel. Simply hold the bottle over the flame, turning it so that the entire scored line heats up. You will see black soot develop where the flame contacts the bottle. This will wash off easily. Now that the line has been heated, turn the bottle smoothly back and forth so that the flame runs along about an inch or two of the scored line. This consistent heat along a portion of the line will result in a cracking sound.
If you have a towel handy, you can wipe off the soot and you will see the crack running through the bottle. Rotate the bottle so that the candle flame is positioned over the next segment of the scored line, and repeat. When the entire line is almost to the end, start pulling slightly as you heat the last few eighths an inch. The bottle will pull apart in your hands!
Use a diamond grit sanding pad to smooth and polish the cut edges. I like to create a small bevel both inside and outside to ensure that there are no sharp edges. Just hold the sanding pad at a forty-five degree angle to the lip of the glass, and sand away.