(0,0)

The Cartesian Coordinate System

I

IVIII

II

+,--,-

+,+-,+

Y+

Y-

Z+

Z-

X+X-

• Basis for plotting all machine table positions

• The left/right axis is X (East/West)

• The front/back axis is Y (North/South)

• Consists of four quadrants

• Points are plotted as (X,Y) Pairs

• Negative numbers have (-) prefix

• Positive numbers have no prefix

• Where the X and Y axes cross is the (0,0) point

• The up/down axis is Z and controls the tool height

• Default zero position of the X Y plane

• After power up the machine must be Homed

• The spindle is located at the Machine Zero position after Homing

• The machine may now be programmed with reference to Machine Zero

The Home Position

Absolute Positioning and Linear Movement

• All points used for movement are plotted using their absolute position from the (0,0) point or Active Origin

• CNC programming uses G codes to execute commands

• G codes consist of a G followed by a number - like G90

• G90 is the command to Enable Absolute Positioning relative to the active origin

• G90 is a Modal and Default command

• Modal commands stay active until they are intentionally cancelled or replaced by another command.

• Non-Modal commands are automatically cancelled or replaced as soon as they are completed.

• Default commands become active when the machine is powered up, the reset button is pushed, or after an M30 command.

AB

CD

(6,7)(-5,8)

(-7,-1)(2,-2)

(X value, Y value)

Absolute CoordinatesDrawing C.1

97

65

34

82

10

13

25

76

89

4

98

67

53

42

01

13

24

65

79

8

29 78 6 5 4 3 1 0 1 32 4 85 6 7 9

AB

C D

1 3 4 5 6 7 8 920123456789

+X-X

+Y

-Y

ABCD

EFGH

Write the Absolute X,Y locationsin the chart below

Absolute CoordinatesDrawing C.2

97

65

34

82

10

13

25

76

89

4

98

67

53

42

01

13

24

65

79

8

29 78 6 5 4 3 1 0 1 32 4 85 6 7 9

AB

C

D

EF

G

H

1 3 4 5 6 7 8 920123456789

+X-X

+Y

-Y

Label the points of the partusing Absolute Coordinates

20

30

A

B C

D

Part 1

D

A

B

C

Part 2

Part 3 Part 4

B

C

D

A

C

D

A

B

D

A

B

C

Exercise C.3

In each of these parts the origin has been placed in a different corner.

Fill in the X and Y values for each point with regards to the part origin.

Linear Movement

• G00 Enables rapid movement of the machine.

– Is never used for cutting.

– Is modal and default.

• G01 Enables linear movement using a specified feed rate.

– F is followed by a number (units per minute)

– Is modal

Examples:

G01 F30 - Specifies linear movement with a feed rate of 30 units per minute

G01 F10 - Specifies linear movement with a feed rate of 10 units per minute

of motion required for G90

Label the points of the part using the type

Exercise C.7

20

30

A (0,0)

B C

D

10

IPM

12 IPM

12 IPM

RAPID!

A-B

B-C

C-D

D-A

G 90

Point

Motion

X

Y

Feedrate

______ ______ ______ ______

______ ______ ______ ______

______ ______ ______ ______

______ ______ ______ ______

A-B

From - To Motion X

X______ Y______

Y Feedrate

B-C

C-D

D-E

E-A

______

______

______

______

______

X______ Y______

X______ Y______

X______ Y______

X______ Y______

F______

F______

F______

F______

F______

Drawing C.8

Enter the motion type, the X & Y values, and thefeedrates in the table below.

End

G03Counter

ClockwiseClockwise

G02

Start

End

Arc Motion G02 & G03

• Cutting arcs and circles requires the simultaneous movement of two axes. This is called Interpolation.

• G02 - Is the command for Clockwise Interpolation

• G03 - Is the command for Counter Clockwise Interpolation

• Both G02 and G03 will use the active feedrate or they can be assigned a new feedrate.

1. 2.3. 4.

5.

6.

7.8.

9.

10.11.

12.

Drawing D.2

Specify Motion Codes: G01, G02, G03

G03 G03 G01 G02 G01

G03 G02 G02G03

G01 G01G02

The Radius Method

The Radius Method is used to cut arcs.

This command incorporates the Direction (G02 or G03), the Endpoint (X,Y), the Radius of the arc, and the

Feedrate of the desired cut.

G03 X-10 Y10 R10 F200.

Start (0,0)

End (-10,10) 200 MM

PM R10

Origins (Osai)

• Cartesian Coordinate Systems may be located anywhere on the machine table.

• The (0,0) points or the home positions of these systems are called origins

• The Z 0 or home position for these systems is set at the top of the CNC worktable (vacuum pods)

• The machine table coordinates of these origins are stored in the controller’s memory

• The Osai 10 Series Controller can create and save up to 10 origins

• These origins are saved in a data table referred to as the Origin Table

• When an origin is made active all subsequent G90 positions are plotted in reference to the active origin.

UAO - Use Absolute Origin

• The UAO code is used to activate a specific origin (1-10)• All G90 (Absolute) positions will be in reference to this

origin• Deactivates all other active origins for the declared axes• Is modal

Examples:

(UAO, 1) = Origin number one is made active for all axes

(UAO, 6, X, Y) = Origin number six is made active for the X and Y axes only

(UAO, 0) = Reactivates the Machine Home position for all axes

UTO (UOT) - Use Temporary Origins

• Used to temporarily offset an origin along the specified axes

• All G90 (Absolute) positions will be in reference this active offset origin

• UTO Deactivates all other active origins for the declared axes

• Is modal

Examples:

(UTO, 1, X-.5, Y.5, Z2) = Activates a temporary offset for origin 1 at X-.5, Y.5, and Z2.

(UTO, 5, Y-.3, Z2) = Activates a temporary offset for origin 5 at Y-.3, and Z2. (no X offset)

Z 0 Position

CMS RouterSpindle

CMS RouterSpindle

CMS RouterSpindle

A BC

A. Z 0 with Origin 1 Activated. Example: (UAO,1)

B. Z 0 with Origin 1 Activated and Part offset activated. Example: (UTO, 1, Z1.181)

C. Z 0 with Origin 1 Activated and Part offset and Tool length compensation. Example: (UTO, 1, Z1.181)

h7

Z=0Z=0

G79 –Absolute Reference to Home Position

• Default (0,0) point for (X, Y) coordinates are located at the center of the main spindle

• Zero for the “Z” axis is at the top of the “Z” stroke

• Straight line moves only, no arcs or circles

• Movements may be performed in either Rapid or Feed speeds (G00 / G01)

• Is Non-modal

• Generally used for moving the machine to safety positions

G79 Programming

Drawing C.9

G79 G00 X79 Y31

CMS Worktable

Router spindle inhome position.

31.00

76.00

M06 Tool Change

• Tools may be automatically loaded from the tool holder or manually inserted by hand using the M06 code

• Tools are designated by a T followed by the tool holder number of the tool

Example: load tool number 5

T5 M06

G300

(In auto mode a G300 must follow a T# M06 command.)

To empty the spindle, use T0 M06. After the spindle comes to the front of the machine, press the RESET button, then type T0 M26 (MDI Mode)

Try not to interrupt a tool change. (See tool change errors)

Tool Offsets – h

• The tool length and tool diameter are both manually entered in the offset table and stored in the controller’s memory

• When a tool change is made the tool offset information is read from the offset table location corresponding to the h number

• The offset table can store over 300 offset combinations

Examples:

h1 = Tool length and diameter values are read from offset table location 1

h99 = Tool length and diameter values are read from offset table location 99

h0 = Tool length and diameter offset values are deactivated

The h must always be typed in lowercase for this function.

Tool

Tool Length =

Spindle Nose to

Tool Tip

Tool Cone

Tool Cone inRouter Spindle

Tool

Drawing H.1

Controlling Spindle Rotation

• M3 is the code for clockwise rotation

• M5 is the code for spindle stop

• The speed is always in Rotations per Minute (RPM)

• An S code after an M3 sets the RPMs

Examples:

M3 S4500 – Clockwise rotation at 4500 RPM

Ending the Part Program

• M30 is at the end of of all programs

• M30 resets the machine to defaults

• M30 rewinds the program

• M30 deactivates any active origins

Programming

Requires a half inch mill bit from tool holder position 5. This tool runs clockwise with coolant at 4500 RPM at 10 IPM. The length and diameter values are stored in offset table position 5. The part thickness is 0.75 inches.

15.0

15.0

1.01.0

Part thickness: .75"

;PART PROGRAM NAME = SQUARE 15X15;1/2” DIAMETER STRAIGHT TOOLN1 G00 G79 Z0N2 (UOT,1,X0,Y0,Z.75)N3 T5 M06N4 G300N5 h5N6 M13 S4500 M7N7 X0 Y-1N8 Z1N9 G01 Z-.78 F10N10 G01 G42 X0 Y0 F10N11 Y15N12 X-15N13 Y0N14 X0N15 G40 X1N16 G00 Z1N17 G79 Z0N18 G79 X0 Y64N19 h0N20 M05 S0N21 M30

CODE EXPLAINATION;PART PROGRAM NAME = SQUARE 15X15 Comment line for program name;1/2” DIAMETER STRAIGHT TOOL Comment line for tool descriptionN1 G00 G79 Z0 Rapid move to machine Z 0 / Safety moveN2 (UOT,1,X0,Y0,Z.75) Use origin 1, set Z0 to top surface of partN3 T5 M06 Tool change N4 G300 Tool change sub-programN5 h5 Use tooling offset table position 5 valuesN6 M13 S4500 M7 CW spindle @ 4500 RPM with int/ext coolantN7 X0 Y-1 Position machine to 1 inch (Y) away from partN8 Z1 Move tool end to 1 inch above partN9 G01 Z-.78 F10 Move tool end to just below part @10IPMN10 G01 G42 X0 Y0 F10 Enable TSR comp , move to 0,0 @10IPMN11 Y15 Move to upper right corner (0,15)N12 X-15 Move to upper left corner (-15,15)N13 Y0 Move to lower left corner (-15,0)N14 X0 Move to lower right corner (0,0)N15 G40 X1 Disable tool diameter compN16 G00 Z1 Rapid move tool tip to 1 inch above partN17 G79 Z0 Move to machine Z 0 / safety moveN18 G79 X0 Y64 Park machine away from partN19 h0 Disable tool offset compensation valuesN20 M05 S0 Spindle Stop (Cancels M13)N21 M30 End of Program – Reset / Rewind

Program Sections

;PART PROGRAM NAME = SQUARE 15X15;1/2” DIAMETER STRAIGHT TOOL

“Comments”

N1 G00 G79 Z0N2 (UOT,1,X0,Y0,Z.75)N3 T5 M06N4 G300N5 h5N6 M13 S4500 M7N7 X0 Y-1N8 Z1

“Start”

Program Sections

N9 G01 Z-.78 F10N10 G01 G42 X0 Y0 F10N11 Y15N12 X-15N13 Y0N14 X0

“Working”

N15 G40 X1N16 G00 Z1N17 G79 Z0N18 G79 X0 Y64N19 h0N20 M05 S0N21 M30

“End”

Exercise D1Write a similar program to cut this part in a CCW direction. Use Origin 5 and start at (0,0). This part requires a1/2” finger bit that is stored in the Automatic Tool Changer position number 2. The length and diameter of this tool are being stored in offset table location number 201. This tool cuts at 4500 RPM and has a feed rate of 10 IPM. The part is 0.5” thick.

G02 X4 Y11.5 R.5G01 Y8.5G02 X3.5 Y8 R.5G01 X0Y0G40 Y-1G00 Z1G79 Z0G79 X0 Y64h0M05 S0M30

;Exercise D1 – Osai – 0210;1/2 INCH STRAIGHT CUTTERG00 G79 Z0(UTO, 5, Z.5)T2 M6G300h201M13 S4500 M7X-1 Y0Z1G01 Z-.53 F10G42 X0 Y0X20Y16X0Y12

Code for D1

Exercise L.2

Write a program to cut the part shown below. Start at the plus sign and go CCW around the part. Use Origin 1. This part requires a 1” diameter router bit that is stored in the Automatic Tool Changer position number 8. The length and diameter of this tool is being stored in the offset table position number 47. This tool runs at 4500 RPM with a feed rate of 10 IPM. Use 8 IPM for lead in only. The part is 1.5” thick.

Exercise L.2 Code;(Exercise L.2 - Osai);(1 INCH STRAIGHT CUTTER)G00 G79 Z0(UTO,1,Z1.5)T8 M6G300h1M13 S4500 M7X0 Y-1Z1G01 Z-1.53 F10G42 X0 Y0

Y10X-4G02 X-8 R2G01 X-18G03 Y0 R5 G01 X-8G02 X-4 R2G01 X0G40 X1G00 Z1G79 Z0G79 X0 Y64h0M05 S0M30

Exercise L.4Write a program to cut the part shown below. Use Origin 1. This part requires one tool, a 3/8” straight cutter that is stored in the Automatic Tool Changer position number three. This tool runs at 4500 RPM with a feed rate of 10 IPM. The length and diameter of this tool is being stored in the offset table position number three. The part is 3/8” thick.

(0,0)

18.0

9.0

R3.0

3.0

3.0

Four places

R1.01.0

Exercise L.4 Code;(Exercise L.4 - Osai);(3/8 INCH STRAIGHT CUTTER) G00 G79 Z0(UTO, 1, Z.375)T03 M06G300h3M13 S4500 M07X0 Y-1Z1G01 Z-.41 F10G42 X0 Y0G02 X3 Y3 R3

G01 Y12G02 X0 Y15 R3G01 X-18G02 X-21 Y12 R3G01 Y3G02 X-18 Y0 R3G01 X0G02 X1 Y-1 R1G40 D0G00 Z1G79 Z0G79 X0 Y64h0M05 S0M30