CNC Cutting Parameters and Speeds/Feeds 2

Question 1

According to Taylor's tool life equation (VTⁿ = C), what happens to tool life as cutting speed increases?

Accepted Answer

Tool life decreases as cutting speed increases

Answer

Tool life increases proportionally with cutting speed

Answer

Tool life is unaffected by cutting speed changes

Answer

Tool life first increases then sharply decreases

Question 2

In CNC turning, feed rate is most commonly expressed as:

Accepted Answer

Inches per revolution (IPR)

Answer

Inches per minute (IPM)

Answer

Surface feet per minute (SFM)

Answer

Millimeters per tooth (mm/tooth)

Question 3

If you switch from a 2-flute to a 4-flute end mill at the same RPM and want to maintain the same chip load per tooth, you must:

Accepted Answer

Double the feed rate

Answer

Keep the feed rate identical

Answer

Halve the feed rate

Answer

Quadruple the feed rate

Question 4

What does the G96 code activate on a CNC lathe?

Accepted Answer

Constant surface speed (CSS) mode

Answer

Fixed RPM (constant spindle speed) mode

Answer

Thread cutting cycle

Answer

Rapid traverse positioning mode

Question 5

Which cutting parameter has the greatest direct influence on surface finish quality in CNC milling?

Accepted Answer

Feed rate

Answer

Axial depth of cut (ADOC)

Answer

Cutting speed (SFM)

Answer

Radial depth of cut (RDOC)

Question 6

Blue or heavily discolored chips produced while machining steel most likely indicate:

Accepted Answer

Excessive cutting speed generating too much heat at the cutting zone

Answer

Feed rate is set too low, causing rubbing

Answer

Insufficient depth of cut per pass

Answer

The cutter has too many flutes for the material

Question 7

Radial depth of cut (RDOC) in CNC milling describes:

Accepted Answer

The percentage of the tool diameter engaged radially in the cut

Answer

How deep the tool plunges along the Z-axis per pass

Answer

The distance the tool feeds per full revolution

Answer

The total length of the programmed cutting path