Wow, silly error but I attempted to dry run it by raising the Z in G54. This changed the point of rotation on my G68 and positions were out. So G68 and G54 Z's must match. This is a good way of undercutting without 5-axis programming/post experience. Highly Recommended!

Hello All, We have a part with some undercutting and would like to tilt our spindle head to accomplish the machining. It is a Head-Table Machine. I know in Mastercam I can tilt the C-Plane and T-Plane where the tool is at the angle required, and program regular 3-Axis paths. The simulation looks good. I have attempted to run this with G68 on the Fanuc 15M; That is, tilting the machine work plane just as I have tilted it in Mastercam - to match them up. The path itself looks good, and retracts are along the angle specified, so I know the planes match. Positionally however, the tool is away from the part. I did all the trig in figuring out the new G54 after the spindle has been rotated, but something is still off. Perhaps this is a syntax error in the NC code? Our tilt Syntax in this situation G68 X0. Y0. Z0. I0. J1. K0. R15. It would be great if we could figure this out as we don't have a post for this machine. Thanks for any help!