Michigan CNC Maintenance
Technician Exam Practice Questions
And Correct Answers (Verified Answers)
Plus Rationale 2026 Q&A| Instant
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1. A CNC milling machine uses G-code to control axis movement. What
does G01 typically represent?
A. Rapid positioning
B. Linear interpolation feed
C. Dwell pause
D. Tool change
This code directs the machine to move a straight line at a controlled
feed rate.
2. What safety device must be in place before powering a CNC machine?
A. Coolant system
B. Tool presetter
C. Emergency stop button
D. Workholding jig
An emergency stop provides immediate shutdown capability for
safety.
3. What type of feedback device measures actual axis position on a CNC
machine?
A. Tachometer
B. Switch
C. Linear encoder
D. Thermocouple
Linear encoders provide precise position feedback to the controller.
,4. In a CNC program, the M03 command typically controls what
function?
A. Coolant off
B. Spindle clockwise rotation
C. Tool change
D. Rapid repositioning
M03 starts the spindle in a clockwise direction.
5. Coolant in CNC machines is used primarily to:
A. Lubricate bearings
B. Reduce cutting heat and flush chips
C. Power hydraulic actuators
D. Improve electrical conductivity
Coolant lowers tool/workpiece temperature and clears chips from
the cutting zone.
6. What does the term “backlash” refer to in CNC machines?
A. Electrical noise
B. Mechanical lost motion between components
C. Programmable pause
D. Chip buildup in coolant
Backlash is the slack between mating mechanical parts that can
affect precision.
7. The axis that moves the spindle toward the workpiece on a lathe is
usually:
A. Y axis
B. Z axis
C. X axis
D. C axis
On lathes, the X axis controls cross-sectional travel toward and away
from the part.
8. Which maintenance task should be performed daily on a CNC
machine?
A. Replace bearings
B. Calibrate axes
C. Check lubrication and air filters
D. Replace spindle belts
, Daily inspection of lubrication and air filters prevents wear and
contamination.
9. What is the purpose of a tool offset in CNC machining?
A. Control spindle speed
B. Adjust coolant flow
C. Compensate for tool length and radius
D. Set program comment text
Tool offsets allow accurate compensation for tool dimensions to
ensure correct cutting.
10. A CNC machine runs erratically and displays “Servo Alarm.” This
likely indicates:
A. Insufficient coolant
B. Motor feedback or wiring issue
C. Low compressed air
D. Incorrect G-code comment
Servo alarms commonly stem from encoder or servo amplifier
problems.
11. What measurement device is most accurate for checking a
finished part’s diameter?
A. Ruler
B. Micrometer
C. Tape measure
D. Protractor
Micrometers are precision tools designed for accurate diameter
measurement.
12. In preventive maintenance, greasing linear guides prevents:
A. Electrical shorts
B. Wear and corrosion
C. Excessive cutting forces
D. Improper tool offsets
Proper lubrication extends the life of mechanical components.
13. CNC program line numbers starting with “N” are used to:
A. Specify spindle speed
B. Identify sequence order
C. Call subroutines
Technician Exam Practice Questions
And Correct Answers (Verified Answers)
Plus Rationale 2026 Q&A| Instant
Download Pdf
1. A CNC milling machine uses G-code to control axis movement. What
does G01 typically represent?
A. Rapid positioning
B. Linear interpolation feed
C. Dwell pause
D. Tool change
This code directs the machine to move a straight line at a controlled
feed rate.
2. What safety device must be in place before powering a CNC machine?
A. Coolant system
B. Tool presetter
C. Emergency stop button
D. Workholding jig
An emergency stop provides immediate shutdown capability for
safety.
3. What type of feedback device measures actual axis position on a CNC
machine?
A. Tachometer
B. Switch
C. Linear encoder
D. Thermocouple
Linear encoders provide precise position feedback to the controller.
,4. In a CNC program, the M03 command typically controls what
function?
A. Coolant off
B. Spindle clockwise rotation
C. Tool change
D. Rapid repositioning
M03 starts the spindle in a clockwise direction.
5. Coolant in CNC machines is used primarily to:
A. Lubricate bearings
B. Reduce cutting heat and flush chips
C. Power hydraulic actuators
D. Improve electrical conductivity
Coolant lowers tool/workpiece temperature and clears chips from
the cutting zone.
6. What does the term “backlash” refer to in CNC machines?
A. Electrical noise
B. Mechanical lost motion between components
C. Programmable pause
D. Chip buildup in coolant
Backlash is the slack between mating mechanical parts that can
affect precision.
7. The axis that moves the spindle toward the workpiece on a lathe is
usually:
A. Y axis
B. Z axis
C. X axis
D. C axis
On lathes, the X axis controls cross-sectional travel toward and away
from the part.
8. Which maintenance task should be performed daily on a CNC
machine?
A. Replace bearings
B. Calibrate axes
C. Check lubrication and air filters
D. Replace spindle belts
, Daily inspection of lubrication and air filters prevents wear and
contamination.
9. What is the purpose of a tool offset in CNC machining?
A. Control spindle speed
B. Adjust coolant flow
C. Compensate for tool length and radius
D. Set program comment text
Tool offsets allow accurate compensation for tool dimensions to
ensure correct cutting.
10. A CNC machine runs erratically and displays “Servo Alarm.” This
likely indicates:
A. Insufficient coolant
B. Motor feedback or wiring issue
C. Low compressed air
D. Incorrect G-code comment
Servo alarms commonly stem from encoder or servo amplifier
problems.
11. What measurement device is most accurate for checking a
finished part’s diameter?
A. Ruler
B. Micrometer
C. Tape measure
D. Protractor
Micrometers are precision tools designed for accurate diameter
measurement.
12. In preventive maintenance, greasing linear guides prevents:
A. Electrical shorts
B. Wear and corrosion
C. Excessive cutting forces
D. Improper tool offsets
Proper lubrication extends the life of mechanical components.
13. CNC program line numbers starting with “N” are used to:
A. Specify spindle speed
B. Identify sequence order
C. Call subroutines
