1. ## Using 4th axis

I would like to use the 4th axis of my Hitachi Seiki VA40 running under Fanuc 6M-B.
I believe I should use M68 to open the chuck and M69 to close it before using any G commands.
I would like to know the G code command structure for this 4th axis.
Pramod

2. I get you the first part, but what is your intent when open/close chuck for? what kind of 4axis do you have? full 4axis/ just index 4axis 'cause it can make the programming the whole different world.

3. ## Using 4th axis

I have a full 4th axis.
Since the last post I was able to initialize the rotary table with M69 and turn it with handle control.
Similar to the starting G28 command to send the axis to Zero.

G28 X 0.0 Y 0.0 Z 0.0
M69
A 0.0

This sent the machine to Zero positions, the green lights lit up and I could move the rotary table in the handle mode.

I want to turn the part so that I can mill say a groove on the surface of a round bar.
I am going to try and use the G codes used in the X, Y and X axis to move the A axis but am wondering if the feed is going to be in degrees per minute.

I agree that the best way is to try it and see.

4. Hi-

Take a look at your Fanuc 6m-b Maintenance Manual. You will find a few parameters that relate directly to the 4th axis settings; specifically:

-A setting of 0 means the 4th axis is a rotaional axis.
-A setting of 1 means the 4th axis is a linear axis.

Hope this helps.
TFGC

5. I believe that a feed move that includes the rotary axis will be in degrees per minute, otherwise it would be inches per minute.

G01 G91 X1.0 A10. F10. (Degrees per minute)
G01 G91 X-1. F10. (Inches per minute - no rotary movement)
G01 G91 A-10. F10. (Degrees per minute)

Another option is Inverse Time Feedrate, where F= 1/time (in minutes) to complete the move. This requires calculations based on the diameter at the bottom of the tool, etc. It may not be activated on your control.

6. I believe the M code is turn brake on and off. Normally, rotate 4axis all you need is type in Axxx.xx. And when you are machine the the control will take care feedrate, you can have feet per minute

7. I've been wanting to know how to use the 0M-C [4th] button which is located on the full keyboard 0M-C CRT/MDI.w/9" monochrome monitor.

Mine is a rotary table, not a rotary indexer or a tilt indexer.

Greg