# CNC (Computer Numeric Controlled) Machinist Knowledge Assessment Test

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CNC MACHINIST KNOWLEDGE ASSESSMENT.

• 1.

### When referring to CNC programming, which of the following is the command coed to move the tool in the clockwise direction?

• A.

G01

• B.

G02

• C.

G03

• D.

G17

B. G02
Explanation
The correct answer is G02. In CNC programming, G02 is the command code used to move the tool in the clockwise direction. This command is used to create circular or arc motions in the program.

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• 2.

### When referring to CNC programming, which of the following is the program format for circular interpolation in a counter-clockwise direction?

• A.

G90 G01 X_Y_R_F_;

• B.

G17 G02 X_Y_R_F_;

• C.

G90 G01 X_Y_Z_F_;

• D.

G17 G03 X_Y_I_J_F_;

D. G17 G03 X_Y_I_J_F_;
Explanation
The correct answer is G17 G03 X_Y_I_J_F_. In CNC programming, G17 specifies the plane of movement as the XY plane, and G03 is the code for circular interpolation in a counter-clockwise direction. X and Y represent the coordinates of the center of the circle, while I and J represent the coordinates of the arc's endpoint. F is the feed rate.

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• 3.

### When referring to CNC programming, which of the following is the command coed to move the tool in the counterclockwise direction?

• A.

G01

• B.

G02

• C.

G03

• D.

G17

C. G03
Explanation
The correct answer is G03. In CNC programming, G03 is the command code used to move the tool in the counterclockwise direction. G01 is used for linear interpolation, G02 is used for clockwise circular interpolation, and G17 is used to specify the XY plane for circular interpolation.

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• 4.

### When referring to the elements of word address CNC programming, a "1" bit is a representation of a/an _________ condition.

• A.

On

• B.

Emergency

• C.

Off

• D.

Ultimate

A. On
Explanation
In word address CNC programming, a "1" bit represents an "On" condition. This means that when a "1" bit is present, it indicates that a particular element or function is active or turned on. This could refer to the activation of a specific tool, axis movement, or any other operation within the CNC system.

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• 5.

### Calculate the feed per minute when an 8-tooth CNC cutter is rotating at 700 rpm and the chip load is 0.008 inch. The feed per minute will be _______ inches.

• A.

56.0

• B.

44.8

• C.

5.6

• D.

0.7

B. 44.8
Explanation
The formula to calculate the feed per minute for a CNC cutter is:
Feed per Minute (inches per minute) = Number of Teeth × RPM × Chip Load
Given the values:
Number of Teeth = 8 RPM = 700 Chip Load = 0.008 inch
Now, use the correct formula to calculate the feed per minute:
Feed per Minute = 8 teeth × 700 RPM × 0.008 inch Feed per Minute = 44.8 inches per minute

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• 6.

### Which of the following operations will produce a hole with 45 degree chamfers?

• A.

Blind hole drilling.

• B.

Spot drilling.

• C.

Center drilling.

• D.

Counter sinking.

B. Spot drilling.
Explanation
Spot drilling is the correct answer because it is a process used to create a shallow hole with a chamfer or beveled edge at a specific angle, typically 45 degrees. This chamfer allows for easier insertion of screws or other fasteners, providing a more secure and flush fit. Blind hole drilling, center drilling, and counter sinking do not involve creating chamfers, making them incorrect choices for producing a hole with 45 degree chamfers.

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• 7.

### The most common type of feed drives used on CNC machines is the:

• A.

Electric servo motor.

• B.

Hydraulic drive.

• C.

Manual crank.

• D.

Manual/hydraulic system.

A. Electric servo motor.
Explanation
The most common type of feed drives used on CNC machines is the electric servo motor. This is because electric servo motors offer precise control and accuracy in positioning, making them ideal for CNC applications. They can also provide high torque and speed, allowing for efficient and smooth movement of the machine axes. Additionally, electric servo motors are relatively easy to integrate into CNC systems and can be programmed to perform complex movements and tasks.

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• 8.

### When referring to CNC tapping operations, what does the acronym TDS stand for?

• A.

Tap Drilling Speed

• B.

Total Diameter Size

• C.

Tap Drill Size

• D.

Tap Down Speed

C. Tap Drill Size
Explanation
The acronym TDS stands for Tap Drill Size. In CNC tapping operations, the tap drill size refers to the diameter of the drill bit used to create a hole before tapping. This hole is slightly smaller than the final threaded hole to ensure proper thread engagement. The tap drill size is an important parameter to consider when performing tapping operations to achieve accurate and precise threads.

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• 9.

### When referring to CNC operations, an excessive surface cutting speed will result in:

• A.

Extended tool life.

• B.

A longer time to machine the workpiece.

• C.

Rapid tool wear.

• D.

A decreased use of coolant.

C. Rapid tool wear.
Explanation
An excessive surface cutting speed in CNC operations will result in rapid tool wear. When the cutting speed is too high, the tool will experience more friction and heat, causing it to wear out quickly. This can lead to a shorter tool life and the need for more frequent tool replacements. It is important to maintain an optimal cutting speed to ensure efficient and effective machining without causing excessive wear on the tool.

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• 10.

### When referring to common CNC programming structures, which of the following is the best example of an end of block character?

• A.

;

• B.

G

• C.

G00

• D.

%

A. ;
Explanation
The best example of an end of block character in common CNC programming structures is ";". This character is used to mark the end of a block of code or a command in CNC programming. It is commonly used to separate different commands or instructions within a program. The semicolon acts as a delimiter, indicating that the current command has ended and the next command or block of code should be executed.

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• 11.

### What is a major disadvantage of the vertical spindle machining centers?

• A.

They can handle heavy workpieces.

• B.

Chips accumulate on top of the workpiece.

• C.

Some of the spindles have vertical motion.

• D.

The crosslide can move transversally.

B. Chips accumulate on top of the workpiece.
Explanation
A major disadvantage of vertical spindle machining centers is that chips accumulate on top of the workpiece. This can lead to interference with the machining process, affecting the quality and accuracy of the finished product. It can also cause damage to the cutting tools and increase the risk of accidents. Proper chip management and removal are essential to ensure smooth and efficient machining operations.

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• 12.

### When referring to CNC programming, which of the following multiple hole patterns is typically the simplest to program?

• A.

An arc hole pattern.

• B.

A bolt hole circle.

• C.

A linear hole pattern.

• D.

An angular hole pattern.

C. A linear hole pattern.
Explanation
A linear hole pattern is typically the simplest to program in CNC programming because it involves drilling holes in a straight line, which is relatively straightforward and easy to calculate. In contrast, an arc hole pattern requires more complex calculations to determine the radius and angle of the arc, while a bolt hole circle involves programming multiple holes in a circular pattern. An angular hole pattern would also require additional calculations to determine the angles and positions of the holes. Therefore, the linear hole pattern is the simplest and most straightforward option to program.

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• 13.

### The coolant system of a CNC machine would most commonly be a __________ pump.

• A.

Low pressure

• B.

Medium pressure

• C.

High pressure

• D.

Gravity

C. High pressure
Explanation
The coolant system of a CNC machine would most commonly be a high-pressure pump because it needs to deliver coolant at a sufficient force to effectively cool the machine and remove chips and debris from the cutting area. High pressure pumps are capable of generating the necessary force to ensure proper cooling and lubrication of the machine components during operation.

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• 14.

### What do the X and Z relate to with a CNC faced can cycle having a G94X__Z__F__; code?

• A.

It is the program feed rate.

• B.

It is the incremental dimensions from park location to cutting start and end points.

• C.

It is the absolute dimensions of the cutting start and end points.

• D.

It is the facing canned cycle command.

C. It is the absolute dimensions of the cutting start and end points.
Explanation
The correct answer is that X and Z relate to the absolute dimensions of the cutting start and end points. This means that the values of X and Z in the CNC program represent the specific coordinates in the machine's coordinate system where the cutting operation will start and end. The machine will move to these coordinates to begin and finish the cutting process.

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• 15.

### Which of the following statement is true with respect to CNC multiple repetitive machining cycles?

• A.

It is not possible to program tool nose radius compensation when using repetitive cycles G70-72.

• B.

When programming TNR inside the cycle, you must cancel the compensation inside the cycle.

• C.

It is not possible to program and cancel TNR outside the repetitive cycle

• D.

For pattern repeating cycle G 73 the operator programs the number of rough cuts and the DOC workpiece.

B. When programming TNR inside the cycle, you must cancel the compensation inside the cycle.
Explanation
When using CNC multiple repetitive machining cycles, it is necessary to program tool nose radius (TNR) compensation inside the cycle. However, it is also important to cancel the compensation inside the cycle. This means that the operator needs to ensure that the TNR compensation is turned off or deactivated within the repetitive cycle. This is crucial to ensure accurate machining and prevent any errors or inconsistencies caused by the TNR compensation.

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• 16.

### With CNC repetitive cycle programming, what does the D stand for in the code G71P__Q__U__W__D__S__F__; (rough turning and boring repetitive cycle)

• A.

The ratio of cut from the far to near surface.

• B.

The depth of cut for the roughing pass.

• C.

It is a block number immediately following the G71.

• D.

It tells the CPU how the X value must be adjusted.

B. The depth of cut for the roughing pass.
• 17.

### Which of the following CNC codes relates to "spindle on" counter clockwise at constant surface speed?

• A.

N020 T0101

• B.

N 030 G50 X8.500 Z7.500 S3000

• C.

N040 M04 S500 G96

• D.

N200 M05

C. N040 M04 S500 G96
Explanation
The correct answer is N040 M04 S500 G96. The code N040 indicates the line number or sequence number of the program. The code M04 is the command for spindle on, and S500 sets the spindle speed to 500 RPM. The code G96 is the command for constant surface speed, which means that the spindle will adjust its speed to maintain a constant surface speed as the tool moves across the workpiece.

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• 18.

### With CNC programming it is good practice to program a rapid motion in ____ axis at a time.

• A.

4

• B.

3

• C.

2

• D.

1

D. 1
Explanation
When programming a CNC machine, it is considered good practice to program a rapid motion in one axis at a time. This ensures that the machine moves quickly and accurately in a single direction, minimizing the risk of errors or collisions. By programming rapid motions in one axis at a time, the operator can maintain control and precision over the machine's movements.

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• 19.

### When should a CNC linear interpolation command never be used?

• A.

For programs longer than 27 lines

• B.

Outside the work area.

• C.

For canned programs

• D.

With projects using 4 quarter addressing.

B. Outside the work area.
Explanation
A CNC linear interpolation command should never be used outside the work area because it can cause the machine to move beyond its intended limits, potentially causing damage to the machine or the workpiece. The work area is the designated space where the machine is programmed to operate, and any commands executed outside this area can lead to errors or accidents. It is important to ensure that all commands are within the specified work area to maintain the safety and integrity of the CNC machining process.

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• 20.

### With CNC linear interpolation programming what does the U refer to in G01U__W__F__; (incremental feed motion)?

• A.

The coordinate along the X axis.

• B.

The coordinate along the Z axis.

• C.

The program feed code.

• D.

The linear interpolation code.

A. The coordinate along the X axis.
Explanation
In CNC linear interpolation programming, the U refers to the coordinate along the X axis. This means that when using the G01U__W__F__ code for incremental feed motion, the U value determines the position along the X axis that the tool will move to.

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• 21.

### When applying tool measurement using a master reference tool and work shift, all Z values can be set to a pre-machined workpiece or the:

• A.

Reference point of the machine.

• B.

Face of the chuck.

• C.

X0 point.

• D.

Base of the tool turret.

B. Face of the chuck.
Explanation
When applying tool measurement using a master reference tool and work shift, the Z values can be set to the face of the chuck. This means that the measurement reference point is the face of the chuck, which is the surface where the workpiece is held during machining. Setting the Z values to the face of the chuck ensures accurate and consistent measurements, allowing for precise tool positioning and machining operations.

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• 22.

### Which of the following statement is true with respect to CNC multiple repetitive machining cycles?

• A.

For boring or internal facing the tool must be located above the cored diameter.

• B.

Only absolute values may be used for co-ordinate positions.

• C.

The starting point should be as far away from the workpiece as possible to assist with tool movement.

• D.

For external turning and facing the tool must be located above and in front of the workpiece.

D. For external turning and facing the tool must be located above and in front of the workpiece.
Explanation
The answer is true because for external turning and facing, the tool needs to be positioned above and in front of the workpiece in order to effectively remove material and shape the outer surface. This positioning allows for better visibility and control over the cutting process.

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• 23.

### Which of the following CNC codes deals with a multiple repetitive, rough cutting cycle used for facing operations?

• A.

G94

• B.

G76

• C.

G72

• D.

G68

C. G72
Explanation
The correct answer is G72. G72 is the CNC code that deals with a multiple repetitive, rough cutting cycle used for facing operations. This code is specifically used for facing operations where the tool moves in a back-and-forth motion to remove material in a repetitive manner. G94 is the code for feed per minute, G76 is the code for fine boring cycle, and G68 is the code for coordinate system rotation.

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• 24.

### Refer to the program format of the following canned cycle for threading. G92 X__Z__F__ The value X indicates:

• A.

• B.

The length of the thread including the deceleration distance.

• C.

• D.

The depth of cut for the threading pass.

Explanation
The value X indicates the minor diameter of the thread for external threads.

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• 25.

### With CNC repetitive cycle programming, what does the P stand for in the code G71P__Q__U__W__D__S__F__; (rough turning and boring repetitive cycle)

• A.

The block number of the first tool motion from tool park location for machining the finish profile.

• B.

The block number of the last tool motion completing the part profile and closing the repetitive cycle loop.

• C.

The amount of material left on the diameter for the finish cut.

• D.

The amount of material that is left on the Z faces for the finish cut.

A. The block number of the first tool motion from tool park location for machining the finish profile.
Explanation
The P in the code G71P__Q__U__W__D__S__F__ stands for the block number of the first tool motion from the tool park location for machining the finish profile. This means that the P value specifies the starting point of the tool's motion for creating the finish profile of the part.

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• 26.

### Which of the following CNC codes cancels the mirror image coordinates for double turret turning centres?

• A.

G94

• B.

G76

• C.

G72

• D.

G69

D. G69
Explanation
G69 is the correct answer because it is the CNC code that cancels the mirror image coordinates for double turret turning centres. This means that when G69 is used, the machine will not produce a mirror image of the programmed coordinates, ensuring that the correct machining operations are performed without any unintended changes in the orientation of the workpiece.

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• 27.

### How are CNC "G" codes grouped?

• A.

According to their bit size.

• B.

According to their function.

• C.

Based on their sequence.

• D.

Based on the number of significant digits.

B. According to their function.
Explanation
CNC "G" codes are grouped according to their function. This means that codes with similar functions are grouped together. This grouping helps in organizing and categorizing the codes, making it easier for programmers and operators to understand and use them. By grouping the codes based on their function, it becomes more convenient to locate and select the appropriate code for a specific task or operation on a CNC machine.

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• 28.

### When programming a multiple-start threading operation for a CNC machine, the shift amount is always equal to the ________ of the thread.

• A.

• B.

Depth

• C.

Pitch

• D.

Lag

C. Pitch
Explanation
When programming a multiple-start threading operation for a CNC machine, the shift amount is always equal to the pitch of the thread. The pitch refers to the distance between corresponding points on adjacent threads, such as the distance between two consecutive crests or troughs. In multiple-start threading, multiple threads are cut simultaneously, and the shift amount determines the distance by which each thread is offset from the previous one. Therefore, the shift amount is directly related to the pitch of the thread.

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• 29.

### With CNC linear interpolation programming what does the W refer to in G01U__W__F__; (incremental feed motion)?

• A.

The coordinate along the X axis.

• B.

The coordinate along the Z axis.

• C.

The program feed code.

• D.

The linear interpolation code.

B. The coordinate along the Z axis.
Explanation
In CNC linear interpolation programming, the W refers to the coordinate along the Z axis. This means that when using the G01UW__F__ command, the value specified for W will determine the position along the Z axis where the incremental feed motion will occur.

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• 30.

### In the following typical G10 command block for a Fanuc control, what does the letter "L" stand for? N____G10L___R___T___:

• A.

The block number.

• B.

The type of offset.

• C.

The value of the tool nose radius.

• D.

The tool orientation number.

B. The type of offset.
Explanation
The letter "L" in the G10 command block stands for the type of offset. This means that it specifies the type of compensation or adjustment that will be applied to the tool or workpiece.

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• 31.

### With CNC turning machines and preparatory codes what does a "G01" represent?

• A.

A code that allows the tool to dwell at a location.

• B.

It instructs the control to move rapidly to specific X and Z locations.

• C.

It is a linear interpolation feed rate code.

• D.

It directs the machine control to use to use workpeice coordinate values stored in memory.

C. It is a linear interpolation feed rate code.
Explanation
The code "G01" in CNC turning machines and preparatory codes represents a linear interpolation feed rate code. This means that it instructs the machine control to move the tool at a specific feed rate in a straight line between two given points. This code is used to control the speed and direction of the tool movement during the machining process.

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• 32.

### What diameter must be used when doing spindle calculations for threading operations with a CNC machine?

• A.

The diameter of the bit.

• B.

The major diameter of the thread being cut.

• C.

The outside diameter of the headstock.

• D.

The inside major diameter of the thread being reamed.

B. The major diameter of the thread being cut.
Explanation
When doing spindle calculations for threading operations with a CNC machine, the diameter that must be used is the major diameter of the thread being cut. The major diameter refers to the largest diameter of the thread, and it is essential to consider this measurement in order to ensure proper thread dimensions and fit. The other options mentioned, such as the diameter of the bit, the outside diameter of the headstock, or the inside major diameter of the thread being reamed, are not relevant to the specific calculation needed for threading operations.

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• 33.

### With respect to CNC turning centres which of the following is true with respect to multiple spindle-multiple turret arrangements?

• A.

It is used where work must be machined on both ends.

• B.

It is designed for work that must be machined from both sides at the same time.

• C.

It is the most common arrangement.

• D.

It is used in high production machining.

D. It is used in high production machining.
Explanation
The correct answer is "It is used in high production machining." This means that multiple spindle-multiple turret arrangements are commonly used in situations where there is a need for high production machining. This arrangement allows for simultaneous machining on multiple sides of the workpiece, increasing efficiency and reducing production time.

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• 34.

### When using the right hand rule for identifying an axis, what does the index finger represent?

• A.

The Z axis.

• B.

The Y axis.

• C.

The X axis.

C. The X axis.
Explanation
When using the right-hand rule for identifying an axis in various contexts, such as in physics, engineering, or mathematics, the index finger typically represents the direction of the positive x-axis or the primary axis of reference. This rule is commonly used to determine the direction of rotation, magnetic field lines, or angular momentum, depending on the specific application.

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• 35.

### What type of transducer is a resolver?

• A.

Transitional

• B.

Positional

• C.

Modulated

• D.

Direct

B. Positional
Explanation
A resolver is a type of positional transducer. It converts the angular position or velocity of a shaft or axle to an analog or digital signal, hence its categorization as a positional transducer. Resolvers are commonly used in high-precision applications such as in aerospace and military technologies for their reliability and accuracy in measuring rotation.

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• 36.

### What angle of bed decline do most CNC turning machines have to assist with chip management?

• A.

70-85

• B.

50-65

• C.

30-45

• D.

18-28

C. 30-45
Explanation
Most CNC turning machines have a bed decline angle of 30-45 degrees to assist with chip management. This angle allows the chips to easily slide down and away from the cutting area, preventing them from interfering with the machining process. A steeper angle could cause the chips to accumulate and potentially cause damage to the machine or the workpiece. On the other hand, a shallower angle may not provide enough assistance in chip removal. Therefore, the optimal range for the bed decline angle is 30-45 degrees.

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• 37.

### In which of the following CNC program preparation systems is the program prepared offline then stored on a disc or hard drive?

• A.

Text editor.

• B.

MDI.

• C.

CAM software.

• D.

MMI configuration.

A. Text editor.
Explanation
The correct answer is Text editor. In CNC program preparation systems, the program is prepared offline using a text editor. This means that the program is created and edited on a computer separate from the CNC machine. Once the program is finalized, it is then stored on a disc or hard drive, ready to be loaded onto the CNC machine when needed. This allows for efficient program preparation and easy storage and retrieval of programs for future use.

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• 38.

### With CNC turning machines, the programmed speed for tapping is generally 25 to ____ % of that used for drilling.

• A.

50

• B.

46

• C.

33

• D.

27

C. 33
Explanation
The correct answer is 33. When using CNC turning machines, the programmed speed for tapping is generally 33% of that used for drilling. This is because tapping requires a slower speed to ensure proper thread formation and prevent damage to the tap.

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• 39.

### Which of the following is true with respect to a Preparatory (G) code?

• A.

They turn various functions of the machine on or off.

• B.

They are modal or non modal.

• C.

• D.

It controls directly tool, speed and feedrate functions.

B. They are modal or non modal.
Explanation
A Preparatory (G) code can be modal or non-modal. Modal G codes remain in effect until they are cancelled or replaced by another code, while non-modal G codes only affect the specific line of code they are included in. This means that modal G codes will continue to control the machine's functions until a different code is used, while non-modal G codes only control the machine's functions for the line of code they are included in. Therefore, the statement "They are modal or non-modal" accurately describes the nature of Preparatory (G) codes.

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• 40.

### What principle of measurement does a rotary encoder use?

• A.

Transitional

• B.

Positional

• C.

Indirect

• D.

Direct

C. Indirect
Explanation
A rotary encoder uses the principle of indirect measurement. Unlike positional measurement, where the absolute position is directly measured, an indirect measurement involves determining the position based on incremental changes or transitions. In the case of a rotary encoder, it detects the rotational movement and counts the number of transitions or changes in position to determine the overall position. This indirect measurement method allows for accurate tracking of position and movement in rotary systems.

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• 41.

### What does the semicolon symbol represent with CNC machines and basic addresses?

• A.

It is used for comments and messages in front of the program.

• B.

It is used to skip program blocks.

• C.

It is used to indicate program number for ISO standard.

• D.

It is used at the end of each program block.

D. It is used at the end of each program block.
Explanation
The semicolon symbol is used at the end of each program block in CNC machines and basic addresses. This indicates the end of a specific program block and allows the machine to move on to the next block. It helps in organizing the program and ensuring that each block is executed properly.

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• 42.

### With CNC turning machines and Miscellaneous (M ) codes, what does an "M03" represent?

• A.

Program stop and ends program execution.

• B.

Optional stop used when occasional part inspection may be required.

• C.

The spindle on in clockwise rotation.

• D.

Spindle on in counter clockwise rotation.

C. The spindle on in clockwise rotation.
Explanation
The "M03" code represents the spindle on in clockwise rotation. This means that when this code is executed, the spindle of the CNC turning machine will start rotating in a clockwise direction.

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• 43.

### Which of the following is true with respect to CNC machines and program storage that uses hard drives?

• A.

The tape has to be fast-forwarded or reversed to locate the required program.

• B.

It is historically the only medium for program storage and transfer

• C.

They can be used for storage large amounts of program data in a compressed form.

• D.

They can be affected by viruses but have the largest storage capacity.

D. They can be affected by viruses but have the largest storage capacity.
Explanation
CNC machines that use hard drives for program storage can be affected by viruses. This means that the hard drives can become infected with malicious software that can disrupt the functioning of the machine. However, despite this vulnerability, hard drives have the largest storage capacity compared to other mediums for program storage and transfer. This allows for the storage of large amounts of program data in a compressed form, making it convenient for CNC machines to access and execute the required programs.

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• 44.

### What is the common rotary resolution for most CNC machines in degrees?

• A.

0.0001

• B.

0.001

• C.

0.01

• D.

0.1

B. 0.001
Explanation
The common rotary resolution for most CNC machines is 0.001 degrees. This means that the machine can accurately position and rotate the rotary axis to within 0.001 degrees, allowing for precise and fine-tuned machining operations. A resolution of 0.001 degrees is considered to be very high and is commonly used in CNC machines to ensure accuracy and quality in the manufacturing process.

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• 45.

### Which of the following best describes a PLC.

• A.

RAM connecting directly to binary logic allowing machining logic.

• B.

It is a type of ROM that allows a programmed feedback loop.

• C.

Its function is to develop signals from program data for driving servo motors.

• D.

It allows a CNC machine to be programmed.

B. It is a type of ROM that allows a programmed feedback loop.
• 46.

### When using the right hand rule for identifying an axis, what does the middle finger represent?

• A.

The Z axis.

• B.

The Y axis.

• C.

The X axis.

A. The Z axis.
Explanation
The right hand rule is a convention used in physics and mathematics to determine the direction of a vector or the orientation of an axis. According to this rule, when the thumb, index finger, and middle finger of the right hand are extended perpendicular to each other, the thumb represents the X axis, the index finger represents the Y axis, and the middle finger represents the Z axis. Therefore, in this case, the middle finger represents the Z axis.

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• 47.

### Which of the following is true with respect to CNC machines and program storage that uses perforated or punched tape?

• A.

The tape has to be fast forwarded or reversed to locate the required program.

• B.

It is historically the only medium for program storage and transfer

• C.

They can be used for storage large amounts of program data in a compressed form.

• D.

They can be affected by viruses but have the largest storage capacity.

B. It is historically the only medium for program storage and transfer
• 48.

### With CNC repetitive cycle programming and boundaries which of the following describes park location D?

• A.

The position of the tool clear of the work piece after the profile is machined.

• B.

The last location on the work piece defining the profile to be machined.

• C.

The first location chew off the work piece before defining the part profile to be machined

• D.

The XZ position of the tool before the repetitive cycle G71 is activated.

A. The position of the tool clear of the work piece after the profile is machined.
Explanation
Park location D refers to the position of the tool clear of the work piece after the profile is machined. This means that after the machining process is complete, the tool is moved to a safe location away from the work piece to prevent any potential damage or interference. This ensures that the tool does not accidentally come into contact with the work piece or any other objects, ensuring safety and preventing any potential errors or accidents.

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• 49.

### What is zero suppression when dealing with CNC machines?

• A.

It allows dimensions to be written without the zeros in front of the decimal point.

• B.

It is used to reduce the number of zeros in the full format dimensions.

• C.

It allows dimensions to be written without the zeros after the decimal point

• D.

Where eight digits are required for each dimension.

B. It is used to reduce the number of zeros in the full format dimensions.
Explanation
Zero suppression is a technique used in CNC machines to reduce the number of zeros in the full format dimensions. It allows dimensions to be written without the unnecessary zeros, making the dimensions easier to read and understand. This helps in simplifying the programming and operation of the CNC machine, as well as reducing the chances of errors or confusion.

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• 50.

### What does odd parity mean in reference to CNC terminology?

• A.

Each program character is represented in rows containing odd number holes.

• B.

The number of wires from the controller to the hardware is always odd.

• C.

The RAM is sectored off in odd divisions.

• D.

The hard drive is mathematically tuned to mathematical operations thst result in odd numbers.

A. Each program character is represented in rows containing odd number holes.
Explanation
Odd parity in CNC terminology refers to the representation of each program character in rows containing an odd number of holes. This means that the physical representation of the characters on the CNC machine will have an odd number of holes in each row. This parity check is used to ensure data integrity and detect errors in the transmission or storage of CNC programs. By using odd parity, any error that results in an even number of holes in a row can be detected and corrected.

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• Apr 17, 2024
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• Jun 21, 2013
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