Help with veritical doosan machine / fanuc programming

I would like some help/advice on a movement I would like to do if possible.

I have done a diagram so visually I hope it explains it better than text.

The radius insert in the picture is how it faces operator in the machine. It will be plunging in the X direction plus.


T0303 will be measured by touching front edge of insert and TOP of insert.

T0313 will be measured by touching front edge of insert and BOTTOM of insert.


At the top of the component the insert will be plunging into the diameter under the landing in a X+ direction then feeding down a Z- movement.

As it moves to the bottom of the part it leads into a lip, I would like to switch offsets to T0313 about ½ way down so I can use that side of insert.


My idea behind this is rather than adjust the program individually as all parts are different we can adjust the Z offsets + or - in the corresponding offset of T3 to help with metal on/off, depending on the repair and what is needed per component.

(excuse the drawing it is basic but I hope it explains my situation)

Thanks for any help

any help with this would be appreciated

thanks

The tool can only go a little bit under centerline. You can't send it to the bottom of the part because the turret does not have that much travel. And once you go down to the centerline it means that all of the material is removed all the way around.
I am probably talking out of my ass because I am confused what you're trying to do and why.

I've only used 2 offsets to tightly control groove widths. I cut down one wall, to the center of the groove width. Rapid out, change offsets, cut the other wall and to the center of the groove width.

It worked well because I could make small adjustments to the width without having to edit the program, chamfers, radii, etc.

I don't know what would happen if you called the offset change in the middle of a cut.

I also don't think I would use it to make large changes, a few thou sure, but 1"?
I'd still edit the program to reflect actual Z lengths, otherwise I think it's a crash waiting to happen.

PS. I'm picturing a vertical lathe.

I don't think you can switch offsets in the middle of a cut (never actually tried it).
But I've had different offsets for each side of a grooving tool, that's normal.
Just pick an overlap point on the face of that groove, cut a little past it with one offset, back off switch offsets, and cut from the other direction.
Easy peasy.

Highly NOT recommended to change offsets mid-cut! Too easy to go "boom."
I think Mtndew has the right idea.

Mtndew said:

I don't think you can switch offsets in the middle of a cut (never actually tried it)....

Click to expand...

Yes you can. Years ago, made lots of wheel spindles with 2 critical bearing diameters separated by a taper. We would turn the first, smaller critical diameter using T0202 then while turning the taper the X and Z line also had T0212 to invoke the new offset (usually just a couple to few tenths in X) by the beginning of the larger critical diameter.

However, like Douglas says below, I don't advise it unless one absolutely understands how their machine handles geometry and wear offsets. Since with Fanuc controls there are parameter settings that control whether the high order or low order numbers in a tool call activate the geometry offsets, a method that works on one machine can spectacularly crash another.

DouglasJRizzo said:

Highly NOT recommended to change offsets mid-cut! Too easy to go "boom."
I think Mtndew has the right idea.

Click to expand...

Thanks very much for replies.

I was programming it as mtndew had suggested so that's reassuring I guess, but I was only wondering if there was a way of doing it in same movement etc.

Appears to be leaving the machine open to a nice bang!

thanks for help again