# Turning Calculations 285

This class explains the common calculations necessary to plot the toolpaths for a basic turning program.

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## Class Details

Class Name:
Turning Calculations 285
Description:
This class explains the common calculations necessary to plot the toolpaths for a basic turning program.
Version:
1.0
Difficulty:
Intermediate
Number of Lessons:
19
Spanish
Related 2.0 Class:
Calculations for Programming the Lathe 311

## Class Outline

• Objectives
• The Purpose of Toolpath Calculations
• Facing and Turning Calculations
• Using Trigonometry
• Drilling Calculations
• Using TNRC
• Incorporating TNR Calculations
• Chamfer with TNRC
• Chamfer Without TNRC
• Arc Programming Methods
• Full Arc with TNRC
• Programming an Arc Motion
• Calculating a Radius Without TNRC
• Calculating Leading Edges Without TNRC
• Partial Arc with TNRC
• Finding the Arc Center Coordinates
• Finding the Partial Arc Endpoints
• Summary

## Objectives

• Identify toolpath movements on the turning center.
• Establish the X- and Z-axes.
• Show how toolpath movements form right triangle geometry.
• Calculate the required drill depth.
• Explain how the tool nose radius impacts part size.
• Identify the information required for tool nose radius compensation.
• Describe situations requiring manual tool nose radius calculations.
• Calculate chamfer toolpath coordinates using TNRC.
• Calculate chamfer toolpath coordinates without TNRC.
• Identify two arc programming methods.
• Calculate coordinates for a full arc center using TNRC.
• Identify program blocks used to machine a full arc.
• Calculate full arc radius coordinates without TNRC.
• Calculate full arc start and ending coordinates without TNRC.
• Calculate the theoretical intersection point of a partial arc.
• Calculate the center coordinates of a partial arc.
• Calculate the start and ending coordinates of a partial arc.

## Glossary

Vocabulary Term Definition
approach A small distance that the cutting tool travels before engaging the workpiece. The approach distance is added for safety reasons.
CAD/CAM Computer-aided design/computer-aided manufacturing. CAD/CAM software helps programmers to efficiently design parts and generate part programs.
circular interpolation A circular path that requires multi-axis tool movement. Full arcs and partial arcs require circular interpolation.
cosine In a right triangle, the ratio of the length of the side adjacent to the angle divided by the hypotenuse.
full arc A portion of a circle that forms an angle measuring exactly 90 degrees.
hypotenuse In a right triangle, the side located opposite the right angle. The hypotenuse is always the longest side.
I and K method A method for programming circular interpolation that uses an I code and a K code to indicate the coordinate location of the arc center.
leading edge The portion of the tool nose that contacts a line parallel to the X-axis or Z-axis.
linear interpolation A straight-line path that requires tool movement along more than one axis at once. Chamfers and tapers require linear interpolation.
partial arc A portion of a circle that forms an angle measuring less than 90 degrees.
R method A method for programming circular interpolation that uses an R code to indicate the size of the radius that forms the arc.
ramping A tool movement that gradually engages the cutting tool with the workpiece.
right triangle A triangle containing one angle that measures exactly 90 degrees.
sine In a right triangle, the ratio of the length of the side opposite the angle divided by the hypotenuse.
tangent In a right triangle, the ratio of the length of the side opposite the angle divided by the adjacent side.
tool nose radius The rounded tip on the cutting edge of a single-point tool. The greater the nose radius, the greater the degree of roundness at the tip.
tool nose radius compensation An offset feature used on a turning center that slightly shifts the toolpath for the rounded tip of an insert during contouring, chamfering, and other multi-axis operations.
toolpath The series of coordinate positions that determine the movement of a tool during a machining operation.
trigonometry The branch of mathematics that addresses the measurements and relationships of a triangle and its parts.
X-axis The linear axis that determines the size of the part's radius or diameter.
Z-axis The linear axis that determines the size of the part's length from the face to the base.