We used to say "One year of experience twenty times" with those guys.

I was a Plant Manager in a heavy steel fabrication and machining shop. A bearing on one of the two bull drives for the main vertical boring machine table (up to 30 ft diameter) had failed.

No problem, rush order the bearing in overnight, talk to the two English millwrights doing the job and get on with my day. A couple of hours later the Welding Supervisor comes up to me and says "You better get over to the VBM, there's a problem with the new bearing."

Yup. There was a problem. The bearing was sitting on top of the drive shaft, on a bit of an angle and the outer race was cracked. There goes a $6,000 double tapered roller and more downtime.

The millwright explains he set the bearing on top of the drive shaft and was "tapping it down" with a friggin' sledgehammer when, suddenly it just cracked!

I was astonished. No measuring the inner race, outer shaft, no dry ice, no bearing heater, nothing. Just pound the friggin' thing onto the shaft. They didn't even know what to do with dry ice.

Another bearing rush ordered - different crew to install it, and me supervising after having given detailed instructions about how many thou needed so between freezing/heating the bearing would just drop into place.