Need Help!- G17 G18 G19

[macca_loto]

Hi all im struggling to understand the whole G17 G18 G19 command. I understand what they are and which plane they represent but im unsure what co ordinates i need to specify when i use a G18 and G19 command in conjunction with a G02 or G03. And also if a secify a linear command which way it will go. Looking to use this more often for the purpose of mould making etc and dont have CAM software do everything via G code.

[ger21]

G17
G2 X Y I J

G18
G2 X Y I K

G19
G2 X Y J K

Linear moves don't change when in the G18 or G19 planes. You still use XYZ, which don't change.

[beege]

Originally Posted by ger21 G17 G2 X Y I J G18 G2 X Y I K G19 G2 X Y J K Linear moves don't change when in the G18 or G19 planes. You still use XYZ, which don't change.

Or, more accurately,

G17 G2 X Y I J

G18 G2 X Z I K

G19 G2 Y Z J K

Cutter compensation is affected in the plane you are using too, and in some controls, automatic cycles.

G17 - XY plane, Z is a drilling axis

G18 - XZ plane, Y is a drilling axis, unless its a lathe

G19 - YZ plane, X is a drilling axis

[sinha_nsit]

The direction of circular interpolation (CW/CCW) sometimes causes confusion, because CW/CCW depends on the direction of viewing. For example, if you are facing me, the CW for me is CCW for you.
In circular interpolation, CW/CCW is defined when we look at the origin of the coordinate system (which is always a right-hand system) from the positive side of the third axis. This is the reason why, on front-type lathe, G02 gives CCW arc (the y-axis points away from us).

Sinha

[beege]

Originally Posted by sinha_nsit The direction of circular interpolation (CW/CCW) sometimes causes confusion, because CW/CCW depends on the direction of viewing. For example, if you are facing me, the CW for me is CCW for you. In circular interpolation, CW/CCW is defined when we look at the origin of the coordinate system (which is always a right-hand system) from the positive side of the third axis. This is the reason why, on front-type lathe, G02 gives CCW arc (the y-axis points away from us). Sinha

Same goes for cutter compensation. Always look at the toolpath from the X plus/Y plus/Z plus quadrant of the part to visualize how a G41/G42 are going to work for you.

[sinha_nsit]

Originally Posted by beege Same goes for cutter compensation. Always look at the toolpath from the X plus/Y plus/Z plus quadrant of the part to visualize how a G41/G42 are going to work for you.

I never thought about it. Good information. Thanks.

Sinha

[Mike Mattera]

Another way to keep the Word Address for the Axis designations straight, is to look at the patterns of the Address Words.

X Y Z
U V W Opposing/Incremental Linear Axis. U opposes X, V Opposes Y.
I J K Arc Center Point Designation. I = The Center in X, J = The Center in Y.
A B C Rotary Axis Designation. A Rotates around the X, B Rotates Around The Y.

Mike Mattera

[BarnabyRudge]

I am used to getting some pretty complicated answers here but from what i understand it works like this for me...

1. First, find an image or graphic on the web of these planes so you can
easily imagine them.

2. How does this now fit accordingly to YOUR machine.

3. Place your tool (i imagine a Milk bottle) AS YOU WISH TO USE IT,
IN YOUR MACHINE.
WHICH PLANE WOULD IT NOW BE STANDING ON?

3. The bottle should now steadily be standing in 3D space on WHICH PLANE?

4. My Old 3 axis Johnford SuperVerticals Spindle Turret moves up and down
in Zeta. My bottle is standing directly on the table of the machine.
Its table moves left to right in X as i stand in front of it.
Its table moves back and forward in Y as i stand in front of it.
This means my old johnford is working on the G17 plane.
This also means i can use radius compensation of my bottle,
RL RR or G41 G42 on this G17 plane, using my milk bottle representation
as a tool.

Hope this helps you.