A 0.025" Mistake and a Very Unhappy Fadal | Log 090

I made a mistake on the Fadal: I didn't verify the tool stick-out, and the toolholder buried itself into the steel I was machining. Immediately afterward, things didn't look good. Oil started dripping from the spindle head, I could hear a significant air leak, and the spindle began taking much longer to stop while making some unpleasant squealing noises. I was worried I'd damaged the spindle, but troubleshooting the symptoms led me somewhere much more interesting: the Fadal's air-over-oil hydraulic Hi/Low belt tensioning system. After pulling the covers and tracing the leak, I found the culprit: a ruptured 1/4" hydraulic line on the high-range belt tensioner. The crash had apparently shock-loaded the system hard enough to split the tubing, dumping the oil and leaving the belt without proper tension. Since I had a hard time finding good pictures and explanations of how this system actually works, I figured I'd document what I found. Hopefully it's useful to another Fadal owner someday. If not, at least I'll have a record of the night I thought I'd killed my spindle and instead got an unexpected lesson in how my machine works. Log 090