A jointer and planer are two important woodworking machines that are often used together to prepare rough lumber for use in furniture making, cabinetry, and other woodworking projects. Although they are both used to prepare lumber, they serve different purposes and have different capabilities. In this article, we will explore the differences between a jointer and a planer.

What is a Jointer?

A jointer is a woodworking machine that is used to flatten one face and square one edge of a board. It has a long, flat bed with an infeed table and an outfeed table, and a jointer cutter head with multiple knives that spin rapidly. The board is fed into the jointer with the rough side facing down, and the knives shave off the high spots until the board is flat and straight. Then, the board is flipped over and the freshly jointed face is used as a reference surface for the next step in the process.

The primary purpose of a jointer is to ensure that one face of the board is flat and straight, which is essential for all subsequent machining operations. Without a flat reference surface, it is impossible to achieve accurate cuts with a table saw or other cutting tools.

A jointer can also be used to create a beveled edge on a board, which is useful for creating chamfers or decorative edges. By tilting the infeed table, the cutter head can be set at an angle, which produces a bevel when the board is passed over it.

What is a Planer?

A planer is a woodworking machine that is used to create a parallel and uniform thickness along the entire length of a board. It has a flat bed with an infeed table and an outfeed table, and a cutter head with multiple knives that spin rapidly. The board is fed into the planer with the jointed face down and the rough side up. The knives shave off thin layers of wood until the board is smooth and uniform in thickness. The thickness of the board can be adjusted by raising or lowering the infeed table.

The primary purpose of a planer is to create a uniform thickness for a board. This is important for creating parts that fit together precisely, such as table legs or cabinet doors. A planer can also be used to create a smooth surface on the board, which is necessary for finishing operations such as staining or painting.

While a jointer and planer are both used to prepare rough lumber, they have distinct differences in their capabilities and functions. Here are some of the key differences between a jointer and a planer:

Function: A jointer is used to flatten one face and square one edge of a board, while a planer is used to create a uniform thickness along the entire length of a board.

Cutting Depth: A jointer removes a relatively small amount of material with each pass, typically less than 1/8 inch, while a planer can remove much more material with each pass, up to 1/4 inch or more.

Cutter Head Design: A jointer typically has a cutter head with two or three knives that are set at an angle to the feed direction, while a planer has a cutter head with multiple knives that are set parallel to the feed direction.

Board Orientation: A jointer is used with the rough side of the board facing down, while a planer is used with the jointed face of the board facing down.

Surface Quality: A jointer produces a flat, straight reference face that is essential for accurate machining, while a planer produces a smooth surface that is ideal for finishing.

Conclusion

In summary, a jointer and a planer are two important woodworking machines that are used to prepare rough lumber for use in furniture making, cabinetry, and other woodworking projects. While they have some similarities, they have distinct differences in their capabilities and functions. A jointer is used to create a flat and straight reference face, while a planer is used to create a uniform thickness along the entire length of a board. By using these machines together, woodworkers can prepare rough lumber to the precise dimensions required for their projects, and achieve the highest level of accuracy and quality in their work.