# Haas Lathe: Locating Program Zero 275

This class describes how to determine work offsets and tool geometry offsets on the Haas lathe during setup. Includes Haas CNC Simulators.

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## Class Details

Class Name:
Haas Lathe Classic Controls: Locating Program Zero 275
Difficulty:
Intermediate
Number of Lessons:
14
Spanish

## Class Outline

• Objectives
• Program Zero
• The Work Coordinate System
• Considerations for Selecting Program Zero
• Tool Geometry Offset Methods
• Determining Tool Geometry Offsets Off the Machine
• Considerations for Touching Off Tools Against the Workpiece
• Entering Tool Geometry Offsets: Z FACE MESUR and X DIA MESUR
• Determining Tool Geometry Offsets: Tool Presetter
• Entering Tool Geometry Offsets: Tool Presetter
• Determining Work Offsets
• Entering Work Offsets
• Entering Radius and Tip Offsets
• Summary

## Objectives

• Compare program zero to machine zero.
• Describe the work coordinate system.
• Identify common locations for program zero on the lathe.
• Identify common methods for setting tool geometry offsets on the lathe.
• Describe how to determine tool geometry offsets for tools off the lathe.
• Describe how to determine tool geometry offsets manually on the lathe.
• Explain how to use the Haas control to enter tool geometry offsets with the Z FACE MESUR and X DIA MESUR features.
• Describe how to determine tool geometry offsets with the tool pre-setter.
• Explain how to use the Haas control to enter tool geometry offsets with the tool pre-setter.
• Describe how to determine a work offset on the lathe.
• Explain how to use the Haas control to enter a work offset using Z FACE MESUR.
• Explain how to use the Haas control to enter matching radius and tip offsets.

## Glossary

Vocabulary Term Definition
.0001/.1 A key that sets the jog increment to .0001 inches or .001 mm. The first number, .0001, indicates that the spindle will move .0001 in. for each jog handle click, while .1 indicates the jog feed rate in inches per minute when pressing and holding the jog keys.
Cartesian coordinate system A system that describes the location of an object by numerically expressing its distance from a fixed position along three linear axes. Cartesian coordinates are used to direct machine tool movements.
centerline An imaginary straight line that runs through the center of a cylindrical part. On the lathe, the centerline is parallel to the Z axis.
CHC Classic Haas Control. A popular model of the Haas Automation®, Inc. CNC control. There have been several versions of the CHC since it was first released in 1988.
chuck A device that holds a workpiece in place as it rotates on a CNC lathe. A chuck commonly has three or four jaws that can be adjusted to fit variously sized parts.
Classic Haas Control A popular model of the Haas Automation®, Inc. CNC control. There have been several versions of the CHC since it was first released in 1988.
ERASE PROG A key in the LIST PROG mode key row that clears the last MDI line when in MDI mode.
F2 A function key that, when entering tool geometry offsets on the Haas lathe, inputs the machine's pre-defined centerline offset value.
HANDLE JOG An operation mode key that allows for the manual operation of tool movement via the handwheel or jog buttons.
ID Inner diameter. The interior surface of a hole or feature.
inner diameter ID. The interior surface of a hole or feature.
input buffer A temporary location on a computer that holds all incoming information before it continues to the CPU for processing.
job sheet A document that includes all manufacturing specifications for a lot of parts.
jog handle A dial that is turned by hand in order to manually control CNC machine motions along the axes. The jog handle "clicks" in controlled, measured increments that an operator selects on the keypad.
machine coordinate system An unchangeable coordinate system that has machine zero as its origin.
machine zero The position located at the farthest possible distance in a positive direction along the machine axes. Machine zero is permanently set for each particular CNC machine.
MDI/DNC An operation mode key that lets an operator enter and execute program data without disturbing stored data when pressed once or execute programs from a centrally located computer storage device when pressed twice.
NEXT TOOL A key on the Classic Haas Control that is used when setting tool geometry offsets to index the turret to the next sequential tool.
OD Outer diameter. The exterior surface of a cylindrical part of feature.
OFSET The display key on the Haas control that shows the various programmed offsets.
outer diameter OD. The exterior surface of a cylindrical part or feature.
part program A series of instructions used by a CNC machine to perform the necessary sequence of operations to machine a specific workpiece.
program zero The position that acts as the origin for the part program of a particular workpiece. This position is unique to each workpiece design, and it is selected by the part programmer.
qualified tooling Tooling used with the lathe that consists of separate clamping units and cutting heads that are interchangeable. The position of each cutting edge is held to very tight tolerances.
radius offset An offset used on the lathe that slightly adjusts the tool to compensate for the rounded tip of an insert during contouring, chamfering, and other multi-axis operations.
stylus The square-shaped tip at the end of the tool presetter that records a tool's offset position once the tool contacts one of its four edges.
tip offset An offset used on the lathe that indicates one of nine possible orientations for a particular tool. Tip offsets are used in conjunction with radius offsets.
tool geometry offset An offset used on the lathe that accounts for variations in tool length along the X axis and Z axis. Each tool loaded in the turret requires its own geometry offset.
tool nose radius compensation TNRC. The use of G codes with radius and tip offsets to compensate for the rounded tips of cutting inserts. If tool nose radius compensation is used for a tool in the part program, the operator must enter a radius and tip offset for that tool.
tool presetter A device on the lathe used to quickly determine tool geometry offsets on the X axis and Z axis. The tool tip contacts the stylus of the tool presetter, which instantly records the turret position in the Tool Geometry Offset screen.
TURRET FWD A key on the Haas lathe that indexes the turret to the next sequential tool.
work coordinate system A variable coordinate system that has program zero as its origin.
work offset An offset used to adjust the location of every tool loaded in the turret. On the lathe, the work offset is typically added only for the Z axis.
WRITE/ENTER A key on the Haas control that acts as a general enter key.
X DIA MESUR A key on the Haas lathe that automatically stores the X axis position as a tool geometry offset for a tool that is properly touched off against the workpiece surface. X DIA MESUR prompts the operator for a diameter measurement.
Z FACE MESUR A key on the Haas lathe that automatically stores the Z axis position as a tool geometry offset for a tool that is properly touched off against the workpiece surface. Z FACE MESUR is also used to set a Z axis work offset.