A gang saw is a type of power saw that makes several cuts simultaneously. Typically, a gang saw operates as a saw and conveyor, pulling logs across its blades to cut an entire section into planks with one pass. Older versions of these tools used a reciprocating saw design, where the blades are perpendicular to the cutting surface, or a circular saw. The most common modern gang saw is the band saw.
A typical modern gang saw is often one of the middle steps in processing a tree into lumber. Before the tree reaches the saw, it goes through a series of single blade saws that remove the bark and outer variations in the tree. After these steps, the wood is shaped like a large rectangular box.
This box is sent to the gang saw, where it is made into planks. These saws have multiple blades, each an equal distance apart. Most gang saws usually have some sort of conveyance mechanism that connects to the wood, often a belt or chain pull system. This allows the users to set the speed by which the wood moves across the blades. This is important, as wood that moves too slowly may chip, and wood that moves too fast will bind the blades.
Typically, the blades on a gang saw are adjustable. This allows workers to change the width of the processed planks to fit desired specifications. This saves the company from needing multiple saws to cut wood of different widths.
Older gang saws were often reciprocating saws. This design uses vertical saw blades that move up and down. These saws worked well, but used a lot of power and had severe limitations on the size of the wood they could accommodate. The length of the blades was a fixed amount—larger blades required stronger motors and tougher blades.
After a few years, many mills switched to circular gang saws. These saws have large spinning blades in the lower deck of the saw. They were easier to use than the large reciprocating saws and used less power. On the other hand, the size of the wood that could be cut by these saws was still limited to the radius of the blades the machine was equipped to use.
Modern gang saws are band saws. These saws feature a spinning band with saw teeth that continuously move around a preset track. Band saws have an upper and lower section, which limits the overall size of the wood that may pass through, but the width is a limitation of design rather than technology or material like older saws.