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Cut trouble on Fanuc 6T

martinsu01

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Joined
Sep 21, 2025
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I just got an old Mori Seiki SL-1 with a Fanuc 6T control. It's my first time using this kind of setup, and I've been learning as much as I can. I got the RS-232 working and was able to load a post processor that seems to work fine.

Here's my problem: I set the tool offsets using a dial indicator on the chuck face, and Z looks okay. But when I try a simple facing cut, I get a Z overtravel alarm before the tool even touches the part. It feels like the machine thinks the stock is behind the chuck. Maybe my G50 or home setup is wrong?Any advice on how to set the zero point right or check where the machine thinks home is? Thanks a lot!
 
But when I try a simple facing cut, I get a Z overtravel alarm before the tool even touches the part.
hi martin. yeah, the Z axis overtravel alarm usually means your machine thinks the G50 zero point is somewhere impossible.
A common mistake is to set the G50 Z value as a positive number when it should be a negative distance from the machine home position. Try changing the sign on your G50 Z value and see if that fixes it
 
Check your G28/G53/Z axis home position and make sure your G54 work offset matches where your dial indicated zero is. Look, a quick way is to jog to your part zero slowly and verify the DRO matches your intended Z before running the cut
 
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