Here are some sources of information I’ve found useful.
Links
Kato, Chutaro: Effect of Knife Chipbreakers on Surface Finish An excellent study of chip formation that was done using a super-surfacer, which duplicates the cutting action of a hand plane. The cutting angle used was 40º, which is typical of a Japanese hand plane used for softwoods. Comparing these images with those of Dr. Norman Franz (see Appendix I of Leonard Lee’s book on sharpening) gives a more complete idea of the types of chip formation that result from different cutting angles. [This link stopped working recently, so I’ve posted an edited version of the study on this page.]
Mark Hennebury’s Website on Supersurfacers A supersurfacer is a piece of power equipment used in Japan to give a fine finish to lumber. It uses the same cutting geometry as a hand plane: a fixed blade with a cap iron, a tight mouth, and the ability to skew the cut. Mark Hennebury has learned to tune these machines to a high level of performance and has posted much useful information and some amazing pictures of the shavings and wood surfaces a supersurfacer can produce.
Reference Works
The Leitz Lexicon: Handbook for Woodworking Machine Tools, Edition 1, Leitz GmbH, 1997. This is a technical handbook that describes the Leitz product line of saw blades, shaper cutters and other cutting tools. It has a section on cutting tool principles and some electron microscope images of worn edges that I would have used on this site if they had not been copyrighted.
Understanding Wood by R. Bruce Hoadley, Taunton Press, 1980. The chapter on Machining Wood has good illustrations of chip formation at various cutting angles.
The Complete Guide to Sharpening by Leonard Lee, Taunton Press, 1995. The comprehensive theoretical and practical information about tools and sharpness in this book make it indispensable. Chapter 2 (The Physics of Severing Wood Fibers) gives a detailed analysis of how edge tools cut in different situations.
Magazine Articles
Japanese Planes Demystified by Carl Swensson, Fine Woodworking #145, November/December 2000, p. 68. The author recommends a chipbreaker edge angle of 75º.
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