Exam Practice Questions And Correct

Ohio CNC Programmer Certification Exam Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2025|2026 Q&A | Instant Download Pdf

• In CNC machining, what does G-code primarily control?

a) Machine speed only

b) Tool selection only

c) Workpiece dimensions only

d) Machine motion commands

Rationale: G-code provides instructions for movement such as linear

and circular motion.

• What is the function of M-codes in CNC programming?

a) Coordinate setup

b) Machine auxiliary actions

c) Tool offset adjustments 1 / 3

d) Placement of work coordinates

Rationale: M-codes control operations like coolant on/off, spindle

start/stop.

• Which G-code represents rapid positioning?

a) G03

b) G92

c) G00

d) G21

Rationale: G00 is used for fast non-cutting tool movement.

• What does G01 indicate?

a) Circular interpolation

b) Machine home

c) Linear interpolation at feed rate

d) Tool change

Rationale: G01 commands straight-line movement at programmed

feed.

• G02 is used for which motion?

a) Counterclockwise arc

b) Clockwise arc

c) Tool length offset

d) Feed stop

Rationale: G02 designates clockwise circular interpolation. 2 / 3

6. G03 is used for:

a) Counterclockwise circular motion

b) Clockwise circular motion

c) Rapid movement

d) Zeroing offsets

Rationale: G03 is counterclockwise arc movement.

7. The coordinate system origin is referred to as:

a) Datum zero

b) Work zero point

c) Machine constant

d) Tool offset

Rationale: Work zero is the reference point for machining

coordinates.

• Which compensation is needed to account for tool radius?

a) Length offset

b) Coolant offset

c) Spindle offset

d) Cutter radius compensation

Rationale: Cutter radius compensation adjusts for tool width during

cutting.

• What does G41 indicate?

a) Cancel cutter comp

b) Right comp

• / 3