g code for a circle

[m8kingit]

Just out of curiosity, can someone show me the difference in the g code that will produce a circle and the one that will produce a square with rounded corners., lol.
I've read all i think i can read about g code, now it's time to put the practical part to work, but after reading the way the radius's are set up in the book, i never really saw a g code for a circle,
please help!
thanks
Mark

[Geof]

G02 I0. J-1. Fn.n

Will (should) cause the machine to execute a full circle of radius 1.0 with the center of the circle locate -1.0 from the position of the tool when this commend is executed. I say should because the J-1. may be interpreted as an absolute position rather than an incremental distance.

There is no single G code for doing a square with rounded corners this has to be done with a combination of G02 for the corners and G01 for the sides. The actual coordinates depend on the location of the work zero but for each corner you stop the distance R back from the corner in the direction X or Y that you are travelling then after the G02 you are at the side in that axis direction but you have moved to a position a distance R along the other axis.

Make yourself a sketch if this description is a bit foggy.

[JapieK]

G112 or G113 cw or ccw
Same as:
X0 Y0 ;
G41 D(<R)X-25 Y-25
G03 X0 Y-50 R25
X0 Y0 J50
X25 Y-25 R25
G01 G40 X0 Y0

you can make it in a para or varia
gr JapieK

[John Walker]

Originally Posted by m8kingit Just out of curiosity, can someone show me the difference in the g code that will produce a circle and the one that will produce a square with rounded corners., lol. I've read all i think i can read about g code, now it's time to put the practical part to work, but after reading the way the radius's are set up in the book, i never really saw a g code for a circle, please help! thanks Mark

Have a look at these, if you are going to do a lot of that sort of work.
http://www.cncprogramdeveloper.com/T...de_macros.html

[warfreak]

well if u use g2 and or g3 plus I / J you can command a full circular toolpath

[avccrml]

what is the easiest way to use cutter comp while doing a lead in or a lead out doing circular interpolation

[angelw]

Originally Posted by avccrml what is the easiest way to use cutter comp while doing a lead in or a lead out doing circular interpolation

Cutter radius comp can't be applied on a circular move. Accordingly, I've found the method shown in the sample code below and the accompanying picture to be the most fool proof and reliable.

This bit of code is to apply a finish cut on a bore that has already been roughed. The size of the lead in/out radius is set to suite the operation, but must be => than the cutter rad comp value being used.

Regards,

Bill

G01 X0.000 Y35.000 F400
G41 G01 X15.000 Y35.000 D01
G03 X0.000 Y50.000 I-15.000 J0.000
G03 X0.000 Y50.000 I0.000 J-50.000
G03 X-15.000 Y35.000 I0.000 J-15.000
G40 G01 X0.000 Y35.000

[dubbs]

sorry guys i'm new to this all and just wanted to know whats the best way to do a circular interpulation my hole is 2.5 inches and my endmill is 1.0inch starting from the center please need some help!!!!!!!!!!!!!!!!!!!!!!!

[dubbs]

its in the center of a 8 x 8 block of steel. i havent been on a cnc mill in a very long time and cant remember how to do it and im manual prgraming the thing if someone can just shoot me a quick lesson on the codes i know go3 and go2 but i and j im having a bit of trouble getting it to work for me anybody gan give me some direction or even a program

[dubbs]

can anyone helpppppppppppp!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[dubbs]

bump

[angelw]

Originally Posted by dubbs sorry guys i'm new to this all and just wanted to know whats the best way to do a circular interpulation my hole is 2.5 inches and my endmill is 1.0inch starting from the center please need some help!!!!!!!!!!!!!!!!!!!!!!!

Following are two examples of cutting a 2.5dia bore. The first example does not use cutter rad comp. and the center of the 1.0 inch cutter is programmed. In both examples, it's assumed that the cutter is at X0 Y0 and down to depth.

Both examples use a Lead In/Out arc. This will avoid a mark being left on the work surface if the cutter were just fed along the circle center line to the circumference of the circle, and fed off along the same path. Using cutter rad comp is better applied using a Lead In/Out to a smaller blend arc as well.

Hope this helps.

Regards,

Bill

No cutter rad comp example
G01 X0.000 Y0.150 Fxxx
G01 X0.600 Y0.150
G03 X0.000 Y0.750 I-0.600 J0.000
G03 X0.000 Y0.750 I0.000 J-0.750
G03 X-0.600 Y0.150 I0.000 J-0.600
G01 X0.000 Y0.150
G01 X0.000 Y0.000

Cutter rad comp example
G01 X0.000 Y0.150 Fxxx
G41 G01 X1.100 Y0.150 D01
G03 X0.000 Y1.250 I-1.100 J0.000
G03 X0.000 Y1.250 I0.000 J-1.250
G03 X-1.100 Y0.150 I0.000 J-1.100
G40 G01 X0.000 Y0.150
G01 X0.000 Y0.000