Absolute programming
Each location is distance from origin
Incremental
Each location is the distance from the previous location
What is CNC?
CNC is computerized numerical control machine that perform complex operations faster, more accurately and consistently.
What is Cartesian Coordinate system?
Consist of axis X Y Z
What is polar coordinates?
Identify locations by defining both an angle and a distance from the origin to a specific location.
Servo motors
Hybrid electric motor that is half motor/half position sensor which can both provide power to move a machine axis and track how far the axis has moved
Climb milling
A method of milling where the cutting tool rotate in the same direction as (pulls into) the direction of the feed.
Conventional milling
A method of milling where the cutting tool rotate in the opposite direction as (pushes against) the direction of the feed.
First step in programming CNC?
Figure out the point of origin.
Conversational programming
Special type of MCU function developed to simplify the machining programming process in which the operator selects the intended type of machining operation from an onscreen menu and the machine prompts the programmer with a series of questions.
Feed rate for milling
Inches per minute
How fast the material is moving into the tool.
Can be in IPM or IPR
Spindle speed
How fast the spindle spin
Choosing an End Mill?
- The shortest possible
- Largest diameter possible
(Within reason)
Cutting radius compensation
The offsetting of the path of the cutting tool in order to adjust for the radius of the cutting tool.
What is an origin?
A point where coordinates are referenced from.
What is MCU?
Machine control unit which is the system of a CNC machine that interprets the program and then uses the information to control machine functions and control axis motion.
Approach point
Approaching the workpiece over air toward the origin of the workpiece.
To calculate
1. Size of the part
3. Size of the material
3. Size of the end mill.
Doing a dry run
- Do it above the workpiece
- Do it at rapid reduce 10% and reduce feed.
Major components CNC motion control?
Drive screws
CNC guideway
Servo motors
G code
Preparatory commands
M code
Miscellaneous functions
Safe-start
Clear any active codes for a new machining cycle
Material removal
Performs machining operations
Program ending
Safety positions tool and axes out of the way
