Deck 12: Lathe Programming

Question 1

The G75 code is used for peck drilling on both Okuma and Fanuc controls.

Answer 1

False

Question 2

How does the drilling cycle work?

Answer 2

The G74 code is used for peck drilling on both Okuma and Fanuc controls; however, some of the words are different. This code works in a very similar manner to the G83 code for milling. We simply position the drill to a safe starting point and then call the drilling cycle. The drill then drills to each incremental peck depth and then retracts to clear the chips. This continues until the programmed Z-depth is reached, at which point the drill returns to the starting position. The Okuma drilling cycle actually goes much farther than just peck drilling. It has several words that allow it to perform a chip-breaking cycle and also a dwell.

Question 3

What is the direction of each lathe axis?

Answer 3

Positive Z points to the right of the spindle, and the positive X direction points toward the back of the machine. This is done because the typical CNC turning center is constructed with the tool mounted on the back side (opposite of the operator). The work zero is generally set to the front and centerline of the finished workpiece.

Question 4

____ cycles are canned cycles that are used to automate stock removal for turning operations.

A) Profile turning
B) Continuous
C) Auto-turning
D) Grooving

Question 5

What rules apply to cutter compensation for turning?

Question 6

____ is an operation in which the tool is plunged into the surface of the workpiece until the proper depth is reached.

A) Drilling
B) Threading
C) Filing
D) Grooving

Question 7

The ____ threading cycle (invoked with G71) allows us to cut a complete screw thread with a single block of code.

A) multi-pass
B) imaginary
C) dwell
D) chip-breaking

Question 8

What is the function of the Fanuc code G28?

A) Spindle speed mode
B) Return to home position
C) Feed rate mode
D) Auto-turning cycle

Question 9

Roughing operations are a very time-consuming issue with lathe programming.

Question 10

CNC turning centers do not use the Cartesian coordinate system for programmed coordinates.

Question 11

The ____-word is the Z-axis increment distance from the start to the center of the arc segment.

A) I
B) J
C) K
D) Y

Question 12

Most finish-turning operations should be performed with the aid of automatic cutter compensation.

Question 13

A ____ tool is a cutting tool used to establish the axial workzeros of a workpiece from which all other cutting tools are referenced through the use of tool offsets.

A) zero setting
B) nonreferential
C) imaginary
D) turret

Question 14

Turning centers follow the convention that the axis aligned with the spindle should be designated "____."

A) I
B) X
C) Y
D) Z

Question 15

____ is a mode of operation that allows a lathe spindle to continuously adjust the spindle RPM as the tool moves through different diameters.

A) Proper feed
B) Constant surface speed
C) Faced surface
D) Continuous RPM

Question 16

The ____ tool tip is the point of intersection formed by two lines that are tangent to a tool nose radius and aligned with the major axes of a lathe.

A) imaginary
B) cutter
C) compensated
D) aligned

Question 17

Describe the grooving canned cycle.

Question 18

Turning tools usually have a small radius ground into the tip of the tool, typically ranging from 1/64" to ____".

A) 1/32
B) 1/16
C) 3/32
D) 1/8

Question 19

Long tools-like drills will tend to stick out significantly past the edge of the zero setting tool.

Question 20

What is the major limitation of tool tip programming?