Chipbreaker: Theory & Use

Chipbreaker-150x150Most bench planes come equipped to eliminate tear-out.

by Kees van der Heiden & Wilbur Pan
pages 32-34

Handplanes are great tools for creating a smooth, finish-ready surface on a board without the dust and noise from a sander. If the board is straight grained and the blade is sharp, it is easy to use a plane. But if the board has some figure, such as that commonly found in curly maple, figured cherry or knotty pine, there is a risk of tear-out.

There are many strategies that can be used to reduce or eliminate handplane tear-out on tricky surfaces. A tighter mouth, a higher bed angle or, if you’re using a bevel-up plane, a steep secondary bevel, are all ways one can attack the problem. But there is a device that comes standard on many bench planes that is equally effective: the chipbreaker.

The ability of the chipbreaker to reduce tear-out can be seen in the photo at left. The cherry board shown was deliberately planed against the grain with a Stanley No. 4, using a stock blade and chipbreaker.

On the near side in the picture, tear-out can be seen, which is expected. On the far side of the board, tear-out is nearly nonexistent. The same plane and blade were used to produce both surfaces. The only difference is that the chipbreaker was set up properly when planing the far side.

Video: Watch the Kato and Kawai video showing the effect of the chipbreaker.
Blogs: Visit the authors’ blogs. (Kees van der Heiden & Wilbur Pan)
Video: In 17 minutes of film, many woodworkers’ views on handplane setup were smashed.
In Our Store: “Handplane Essentials,” by Christopher Schwarz.

From April 2014 issue, #210

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