There are several different types of bar clamp. You need to choose the one that’s most appropriate for the job you are doing.
Sash clamp
A sash clamp is the most common type of bar clamp. It has a simple design, consisting of a long, thin bar and two small jaws. Both jaws can be adjusted – however, one is connected to a screw while the other is free to slide along the length of the bar. The bar has small perforations along it, where a peg is inserted to keep the free jaw in place during clamping.
T-bar clamp
A T-bar clamp is similar to a sash clamp, except is has a bar shaped like a ‘T’ when viewed end-on. The top section of the bar is wide and flat, the purpose of this being to provide greater support and a more rigid structure for clamping larger workpieces, such as wooden doors or frames. This added feature comes at a price, however, as T-bar clamps can be very expensive.
Pipe clamp
A pipe clamp differs from the other types because its bar is circular, rather than rectangular, and shaped like a pipe. This type of bar clamp is generally shorter than the other types, and is used for smaller woodworking tasks, for example gluing two pieces together. Despite the name, it is not designed for clamping pipes.
Quick-release bar clamp
Quick-release bar clamps have a mechanism which allows the jaws to be opened and closed at speed, in order to save time during clamping applications. A quick-release bar clamp is often referred to as a trigger clamp. For more information, see What are quick-release clamps?