Set-Up and Operation for CNC Machining Centers
The first switch that you must set when performing any procedure on a CNC machining center is the:
feed rate override switch
single block switch
mode switch
dry run switch
mode switch
How do you determine the tool length compensation offset number for each tool in your program?
Make it the same as the program number
Add 20 to the tool station number
Make it the same as the tool station number
Make it the same as the fixture offset number
Make it the same as the tool station number
Which of the following is amortized over the course of the production run?
set-up time
programming time
tooling costs
all of the above
all of the above
You normally program an indexing head mounted on a CNC mill as a(n):
Y axis
X axis
C axis
A axis
A axis
What are the two most common operations performed on a CNC lathe?
turning and facing
If you find that the feed rate for a given cutting tool must be overridden when running the first workpiece, what should you do?
Increase the spindle override switch to compensate.
Decrease the spindle override switch to compensate.
Change the feed rate for the cutting tool in the program so that the feed rate override switch can be kept at 100% for the entire cycle.
Be sure to closely monitor every cycle and reset the feed rate override switch every time the tool begins machining.
Change the feed rate for the cutting tool in the program so that the feed rate override switch can be kept at 100% for the entire cycle.
When is it necessary to use trial machining techniques on a CNC machining center?
Trial machining is required for a cutting tool when you are worried that the surface it machines does not come out within its tolerance band the first time it is run.
A percentage added to the final labour cost is called the:
profit margin
What type of CNC milling is used to generate flat geometry?
2-D contouring
What type of system is normally used to generate code for 3-D surfacing?
a CAM system
When do you instate tool length compensation?
Instate tool length compensation in each cutting tool's first Z axis approach
Which mode switch position lets you modify CNC programs?
edit
What is one of the first steps in the planning process?
establishing a machining sequence
What type of operation includes drilling, boring, tapping, thread milling and helical milling?
hole operations
What G code is used to instate tool length compensation?
G43
Name the 3 basic modes of operation on a CNC machining center.
1) manual mode
2) manual data input (MDI) mode
3) program operation mode
Name 3 display screen modes.
Any 3 of the following are correct.
1) position
2) program
3) offset
4) program check
5) alarm
6) service
When ordering material, approximately how much should you allow for a kerf width if parts are cut on the saw?
1/16"
When ordering material, approximately how much should you allow for a kerf width if parts are parted off on the CNC machine?
1/8"
Name the 3 kinds of compensation used on CNC machining centers.
1) fixture offsets
2) tool length compensation
3) cutter radius compensation
Which mode switch position lets you rough position machine axes on a CNC machining center?
jog
Which mode switch position lets you run CNC programs?
auto
What type of cycle can you program to cut internal and external grooves and threads efficiently?
a canned cycle
Finish this phrase:
If you have time to lean, you have time to:
clean.
or deburr parts, inspect parts, set up tooling for the next job etc.
An endmill is programmed to machine a recess to a depth of 0.375, and 0.375 is the target value. After machining with the endmill for the first time, you measure the recess depth and find it to be 0.3734. What must you do?
Decrease the tool length compensation offset by 0.0016
Increase the fixture offset X register by 0.0016
Increase the fixture offset Y register by 0.0016
Increase the tool length compensation offset by 0.0016
Decrease the tool length compensation offset by 0.0016