Good day everybody.

I'm working with a OKUMA ACT3 CNC lathe (with FANUC 6t) perfectly. But when I started cutting long pieces I had to apply linear interpolation to compensate conicity, then I checked that the trajectory was not a straight line, it suffered a distortion (abrupt diameter change, about 0.004 inches).

I change second coordinate of linear interpolation many times (X position), hopping that the failure disappears, but the trajectory doesn't change. This failure just happens some cases, for example when I change tool reference point the failure disappears, or when I change some coordinates after linear interpolation command, but just happens using linear interpolation command.

Its rare for me, because I've never seen this kind of failure. I read the manuals but I can't find a solution. I think its a seriuos problem.

I hope you give me any idea.

Thanks!!!!!!