Canned Cycles: An Introduction
OBJECTIVES
After completing this unit, you should be able to:
- Identify and describe a canned cycle for CNC code
- Identify basic functions within a canned cycle
Canned Cycles
Canned comes from the verb “to can”. We put food into cans. It is canned food. The action of canning food refers to metal cans and glass jars.
The expectation is that the food in the cans will be the same from can to can.
This idea that the type of food (the contents) in the can is the same relates to the concept of repetition.
In CNC code, the canned cycles repeat the same motions.
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A good machinist wants to reduce the amount of coding.
Canned cycles are G-Code commands that take repetitive machine movements that the CNC program can use. Operators do no need to program every motion of the machine. Canned cycles allow for shorter code in the CNC programs.
Canned cycles have codes which are within the larger program: a code within a code.
A canned cycle simplifies coding for repetitious movements.
Helpful Videos for an Introduction to Canned Cycles
- Watch this 7:42 video “Introduction to Canned Cycles” hosted by Practical Machinist.
- Watch this 16:02 video produced from Manufacturing ET: 4476 Canned Cycles
- Here is a deck to support above. Canned Cycles powerpoint.
Canned Cycles are used to simplify CNC codes (programming). Repetitive operations, e.g. drilling, tapping, and boring use canned cycle codes. The repetitive information, the canned cycle, is executed every time a new X- and/or Y-axes is located in the program.
The positioning of a canned cycle in the X and/or Y-axes can be done with G90 (absolute) or G91 (incremental).
Once a canned cycle is commanded, the operation happens at all X-Y coordinates listed in the block.
Some of the canned cycle measurements can be changed after the canned cycle starts. The most important of these changes are the R-plane and the Z-depth. When these are listed in a block with XY coordinates, the XY move is completed. All following canned cycle moves use the new R or Z value.
Rapid moves to the X and Y-axes positions within a canned cycle occur.