The roughest duty my machine sees is the ditches along the highway. I have to be careful, people toss all kinds thing out of their windows and trucks drop things too. Once I hit a 1" solid bar of steel about 18' long with the rotary cutter, man that was some kind of noise, good thing the blades swing and the cutter has a clutch.
The drive shaft and rotary cutter started shimmying to where I thought the cutter and drive shaft were going to come off the machine. I pulled the PTO, investigated and found the steel bar about 5' to the right front of the cutter, I then inspected the blades to see if they were bent which luckily they weren't.
I hit the PTO again and noticed the shimmying leaving the cutter and drive shaft. I think what happens the blades swing and straighten themselves out. I've hit stones, bottles, beer cans and lucky for me I thankfully saw what turned out to be a sex toy sticking up in the grass in time to avoid hitting it. I went around that thing for over a month... I've learned to be on the look out for things hidden in the grass but some get down in the grass so far I miss them.

ray: