Changing post processor to output C axis instead of A axis

[tyler_machine]

My current post outputs A axis movement in place of Y axis with the wrap toolpath option.
I would like to change this to C axis movement.

Has anyone else had this problem?

Thanks for any help.

[johnswetz1982]

It sounds like you have a very strange machine setup. Is there any reason your machine does not follow X>Y>Z to A>B>C usual configuration? C usually rotates about Z which generally only matters if you have another rotational axis, with B (not A) rotating about Y.

[tyler_machine]

The machine is a 5 axis.

It has a B axis which is aligned with the Y axis and a C axis which is aligned with the Z axis.

The problem is, when the B axis is rotated to -90 degrees the C axis becomes aligned with the X axis.

[johnswetz1982]

Thats a BC setup. That is different that what you described in your initial post and follows the normal convention. My follow up is what do you expect your code to look like? From what you are  describing I would expect to see B/C moves. "B" rotates about "Y" and "C" effectively becomes "A" but the code output should still be "C". I used a DMU 50 with the B/C setup like you are describing and it did not use "A" moves. What control would this be for?

[tyler_machine]

The control is a Fanuc 31I.

I've tried the "Fanuc" post, which doesn't output any A, B, or C axis moves.

I've tried the "Fanuc - Inverse Time and A-axis" post, which does output A axis moves, but looks a lot different from the "Fanuc" post.

[jonathanBUCVS]

You'll probably have better luck using a 5 axis post. What machine do you have? If your exact machine is not listed in the post library, you might be able use a similar post, but some of the M codes for clamp/unclamp, etc might be different

[engineguy]

@tyler_machine 

Try the attached PP, it is a Fanuc 5 axis set to have the B axis moving -90/+90 around the Y axis and the C axis doing 360 degrees around the Z axis.

Are you looking for code like this ??

(2D POCKET1)
N30 T4
N35 M06
(4MM FLAT END MILL ALUZIP)
N40 S5000 M03
N45 G54
N50 G00 B0. C0.
N55 M08
N60 G00 X-26.36 Y33.754
N65 G43 Z15. H04

[tyler_machine · Accepted solution]

Well, here's the quick and dirty solution to what I was trying to do.

The Haas with A axis post is closest to what I'm looking for, as far as g code output.

Here's a sample

In the "onOpen" section of the post, I changed the coordinate of the aAxis from "0" to "2"

0 = A output

1 = B output

2 = C output

So everything is still listed as the "A" axis in the post, but I'm now getting the desired output.

Thanks for the help,