Lab glass tubing is a common piece of equipment you cannot avoid in any science lab. You need the glass test tubes to move solutions, transfer contents and for storing. In general, lab glass tubing comes in different sizes. They are also known as culture tubes or boiling tubes. The typical length of lab glass tubing would be 6 inches (approximately 150 mm), 12 inches (approximately 300 mm) or a foot. In some cases, you may have to cut the test tube, so that it suits your experiment or project.
Cutting lab glass tubes is a common procedure followed by chemists and researchers. Some believe that cutting lab glass tubes is an art. With this being said, here are few tips on how to cut lab glass test tubes.
Step by step guide on how to cut lab glass test tubes
First of all, you must have the right lab equipment for cutting lab glass tubes. A steel file will be a great product for cutting glass. The edge of the steel file must be sharp. Use the edge to notch or score the glass. This movement should be done perpendicular to the length of the glass. A single score is more than sufficient. In fact, this is one of the best ways to begin. If you try sawing the glass tube back and forth, you may end up making a big mess. Likewise, choose a light score over the deep ones.
Next, you must execute the procedures safely. You need heavy gloves and proper eye protection. Without gloves the risks of you cutting yourself is high. If you are unable to find gloves, you must wrap a towel around the tube. This will reduce the chances of you being cut.
Before cutting glass tube, you should have a firm grip on the test tube. Place your fingers in the right position. Your fingers should be on either side. Then apply firm but gentle pressure on the test tube. The pressure must be sufficient to snap the tube into two. Once again, be careful with the amount of pressure you exert on the glass tube. You must not end up hurting yourself.
Regardless of the material used to manufacture the glass test tubes, these lap equipment are fragile. You must handle them with care, especially when you are cutting, bending or drawing lab glass tubing.
The final step
Once the glass snaps into two, you will have two tubes with sharp edges. The edges will be extremely sharp. You must polish the edges before using them. The best way to polish edges is with fire. Fire polishing is done by holding the glass tubes to an alcohol or a gas burner. The tube should be heated evenly. Stop heating only when the ends become smooth. Never level the ends in the flame for a very long time. Excess heating will melt the tube and the ends may get blocked. Finally, allow the tube to cool down.
Now, your glass test tubes are ready to be used.