A rake angle is the angle between the leading edge of a cutting tool and a perpendicular to the surface being cut.

Negative Rake is by definition the angle between the leading edge of a cutting tool and a perpendicular to the surface being cut when the blade is AHEAD of the cutting edge.

Plowing Action with a Negative Rake Cutting Tool
The "K" file is an example of a Negative Rake Instrument and it will cut going IN and OUT of a canal.

Positive Rake is by definition the angle between the leading edge of a cutting tool and a perpendicular to the surface being cut when the blade is BEHIND the cutting edge.

Cutting a Chip with a Positive Rake Cutting Tool
A Hedstrom Type File is an example of a Positive Rake Instrument and it cuts only on the way OUT of a canal.


File Name is: RKANGLES.HTM ---- 3/13/07 ----