The Most Expensive Mistake I Ever Made on a Deep Hole Drill
The Setup That Felt Routine I was drilling a batch of titanium shafts for an aerospace customer. The material cost was $800 per shaft. I had 20 shafts to drill, each one 600mm long with a 16mm bore running through the center. The job specification called for a tolerance of H7, which meant the bore had to stay within 0.018mm of the nominal diameter. I’d run similar jobs before without any trouble, so I treated this one like any other production run. ...