First, he checked the tool. The carbide end mill was still sharp. Not that.
Dave knelt and put his palm on the Z-axis ballscrew cover. It was warm. Too warm. A healthy axis runs hot, but this felt like a car engine left running in a closed garage. He grabbed a thermal gun from his toolbox. The bearing housing at the bottom of the screw read 178°F—forty degrees above normal. fanuc 224 alarm
"Or," Dave said, standing up and wiping his hands on a red rag, "I bypass the bearing thermal switch, override the servo torque limit in parameters, and let it run until the bearing welds itself to the screw. That’ll turn an eight-hour fix into a twenty-thousand-dollar spindle replacement and a six-week wait for a new ballscrew assembly. Your choice." First, he checked the tool
He typed in MDI: G91 G01 Z-10. F500. Cycle start. Dave knelt and put his palm on the Z-axis ballscrew cover
He grabbed his flashlight and peered into the machine's guts. The usual suspects: a stuck way cover, a dull tool, a brake that forgot to release.