How does a planer differ from a shaper?

While both shapers and planers are used to machine flat surfaces, grooves, and angular shapes using single-point tools, they differ primarily in their mechanical operation and capacity.1

• Tool vs. Workpiece Movement: In a shaper, the cutting tool is mounted on a reciprocating ram that oscillates to perform the cutting stroke, while the workpiece remains stationary on a table that feeds into the tool. Conversely, in a planer, the cutting tool remains stationary while the workpiece is mounted on a reciprocating table that moves back and forth beneath the tool.123
• Workpiece Capacity: Shapers are generally designed for smaller parts, with the largest models typically limited to a 36-inch cutting stroke. Planers are built to accommodate much larger workpieces, with some machines capable of handling parts up to 50 feet in length.1

In essence, the shaper moves the tool against a fixed workpiece, whereas the planer moves the workpiece against a fixed tool.1