Friday, May 14, 2010

COORDINATES SYSTEM

Before creating the program, we need to know first about the coordinate system.
Coordinate system explain the work areas of the workpiece.
Coordinate system is chosen based on the machine type.

Coordinate system seen from the location of the machine spindle.
Where the axis of the machine that attached Spindle,
that is what determines where the selected coordinate system.

There are three types of coordinate systems, there are G17, G18, G19.
Can be seen in the picture below.


G 17 X-Y PLANE, for vertical mill machine
G 18 X-Z PLANE, for the horizontal milling machine
G 19 Y-Z PLANE, for the horizontal milling machine


vertical Milling machine
Horizontal milling machine

This video shows a horizontal milling machine runs








Wednesday, April 28, 2010

COMMAND CODE for CNC MILLING




To move the axis of a CNC Mill machines, we need a command code known as G CODE.

There are three basic movements of the G Code

1. G00 = Rapid positioning

Tool move linear into programmed position of the work piece with rapid transverse rate (maximal speed).
Movement positioning has 2 methods depend on machine maker.
  • use linier interpolation, many axis move together.
  • non linier interpolation, axis moving one by one.

2. G01 = Linear move

Tool move linear into programmed point position with selected feed rate in Fxxx


3. G02 /G03 = Circular Interpolation

Tool move along a circular arc to the programmed position with feed rate specified in Fxxx.
G02 = making arc with clock wise direction (CW)
G03 = making arc with counter clock wise direction (CCW)


Combination of the three basic movement shape all the contours on CNC Mill machines.
For a simple contour we can write the G CODE manually.
But for a complex contour, we need software that can produce the G Code. They are called CAM software.

This simulation shows the G CODE and movements that occur.








There are lot of CAM Software for example MasterCAM, UniGraphic, Catia, CAM Tool, Cimatron, HyperMill, Delcam PowerMill etc.

Monday, April 26, 2010

CAM for CNC MILLING MACHINE



Before we learn about CAM for CNC Mill, we must know first what CNC milling machines are.

CNC milling machines are machines that each movements are controlled by computers.
It's got the X Y Z axes and also have a main spindle. Spindle is a place to install the tool that is used to cut the workpiece.

This is an axis diagram for 3 axis CNC Machines.

X is left and right movements of the table
Y is foward and backward movements of the table
Z is up and down movements of the spindle

While 5 axis CNC Machines have 2 additional axis, for example A and C axis.


Movements can vary widely depending on the program that we created.

Watch this video.








PowerMill is a Software from Delcam that is used to create programs that will be used on CNC Milling machines.
Powermill can be used for three axis CNC machines and also the five axis CNC Machines.
It has a high ability to create programs for precise, fast and free collisions