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AIT 2019 QH-V2 > CNC Assignments > Flashcards

Flashcards in CNC Assignments Deck (52)
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1

Which style of V-flange tool-holder is most commonly used in North America?

 

- CAT 40

 

2

List two ( 2 ) types of 40 size tapers for machining centers. 

 

- CAT ( Caterpillar ) 

- BT

3

What is the most obvious difference between CAT and BT V-flange tool holders?

 

- Size of the width V-groove around the flange

4

What ensures that the tool-holder and cutting tool remain concentric with the spindle in a milling machine?

 

- Smooth internal tapered surface within spindle engages matching external taper on tool-holder shank

5

What is the purpose of the dimple in the keyway of a tool-holder?

 

- Helps with orientation

( Helps with identifying deeper drive slot ) 

6

If tool station number 2 is not currently in the spindle, what command must be used to place tool number 2 in the spindle?

 

- T02 M06

 

7

What command makes the spindle rotate to the orient position?

 

- M19

8

What codes are used to initiate tool length compensation?

 

- G43 and an H-word

9

List 4 available safety functions, used when verifying a program.

 

- Dry run

- Single block

- feed hold

- distance to go

10

What feature allow you to ignore milling cutter size when calculating coordinates?

 

- Cutter radius compensation

 

11

Most machining centers require feed rate, feed rate in IPM ( inches per minute). What G-code specifies IPM?

 

 

- G94 = Inches per minute ( IPM )

- G95 = Inches per revolution ( IPR ) 

 

12

What is the preferred positioning method, absolute or incremental?

 

- Absolute

13

What G-codes are used to specify Absolute and Incremental positioning?

 

- Absolute = G90

- Incremental = G91

 

14

When programming an arc using directions vectors, what do the I and J values specify?

 

- " I " specifies X-axis components

- " J " specifies Z-axis components

15

What are the 3 G-codes related to plane selection?

 

- G17 = XY plane

- G18 = XZ plane

- G19 = YZ plane

16

List and describe the 2 G-codes used to instate cutter compensation. ( For Milling )

 

- G41 = cutter on left

 - G42 = cutter on right

17

What code cancels cutter compensation?

 

- G40

 

18

How does G28 work?

 

- Zero return command causes two motions to their intermediate points.

 

19

What is G80?

 

- Cancels Canned cycle

 

20

What is G81 for milling?

 

- Standard drilling cycle

( G81 G99 Z-0.375 R0.1 F9. )

21

What is G73?

( Milling )

 

- Chip-breaking peck drilling cycle

( G73 G99 Z-2.15 Q0.2 R0.1 F9. ) 

 

22

What is G83?

( Milling machines ) 

 

 

- Deep hole peck drilling cycle

 

23

What is G84? 

( Milling machines ) 

 

 

- Right hand tapping cycle

( 7/16 - 14 @ 500 RPM ) 

( G84 G99 Z-.065 R 0.1 J3 F3.5.7143 ) 

( J3 = Retract speed ) 

 

24

What is G74?

( Milling machines ) 

 

- Left hand tapping cycle

( G74 G99 Z-.065 R0.1 J3. F35.7143 ) 

( J3 = Retract speed ) 

25

What is G86 for milling?

 

- Standard boring cycle

( G86 G99 Z-0.54 R0.1 F4.5 ) 

 

26

What is G89? 

 

- Counter-boring cycle

( G89 G99 Z-0.375 P0 ) 

27

What type of tap holder is required on older machines?

 

- Special Tension/Compression tap holder

 

28

What is rigid tapping and what are the advantages?

 

- Allow perfect synchronization between spindle reversal at hold bottom and Z-axis motion.

29

How are G86 and G76 different?

 

- G86 ( Standard Boring mill ) Leaves drag-line mark 

- G76 ( Fine Boring mill ) Leaves no marks

30

What is the difference between G85 ( Reaming ) and G81 ( Drilling ) ?

 

- G85 = Feeds to bottom of hole and retracts at the same feed-rate

- G81 = Standard drilling cycle for reaming to save time