Tried a new post hole digger on a rocky job and got a surprise

Got a contract for a fence line in the hills outside Boulder, ground looked tough. My old two-man auger was acting up, so I rented this new hydraulic drive unit, the kind with the separate power pack. Figured it would chew through anything. First few holes went fine, then we hit a patch of what felt like solid rock. The machine started shaking like crazy, then just stopped dead. Turns out, the shear pin was gone, but the real shock was finding a smooth, round river stone about the size of a bowling ball right where the pin sheared. It was perfectly buried. Learned that even the fanciest gear can't beat old ground, and you always need a digging bar and a spare pin kit on the truck, no matter what. Anyone else hit a hidden rock that completely stalled a machine?

2 comments

2 Comments

anthony_lane551mo agoTop Commenter

Ever have one of those days where the ground just decides to fight back? I hit a seam of what we thought was shale with a mini-ex once, turned out to be a slab of old concrete someone just buried. Felt like the whole machine just sat up and sighed. That river stone sounds like it was waiting for you.

perez.elliot1mo ago

Man, that buried concrete slab sounds exactly like the kind of surprise I'd find. I swear my crew and I have a talent for digging up the weirdest junk. We were putting in a post hole last month and hit what felt like solid rock. Took us forever to realize it was an old cast iron bathtub, just filled with dirt. The look on the homeowner's face was priceless. I guess someone really didn't want to pay dump fees back in the day.