alex_wilson79•2mo agoProlific Poster

Had a post hole digger shear a pin on a rocky job in Boise last Tuesday

We were setting 4x4 posts for a cedar fence and hit a patch of river rock about 18 inches down. The shear pin snapped clean, and the auger just spun free. I had to finish the holes with a manual bar, which added half a day. What's your go-to method for getting through rocky ground without wrecking your equipment?

4 comments

4 Comments

harpery472mo ago

Feels like everything's built to handle the easy 90% and just snaps on the hard 10%. Like my phone charger cord frays in the same spot every time, or how traffic flows fine until one person taps their brakes and it all locks up. That shear pin is the same deal, the one weak point that fails so the whole machine doesn't blow. Still sucks to be the guy holding the manual bar though. For rocky spots, I'll sometimes use a digging bar to break up the worst of it first, or even a small demo hammer if it's real bad, just to save the equipment.

ericj452mo ago

Actually, a shear pin is meant to be the weak point. That's the whole design. It's a cheap part that breaks on purpose to save the expensive gearbox. I mean, it totally sucks when it happens and you're stuck, but it's not really a flaw like a fraying cord. The cord thing is bad design, but the shear pin is good design, just annoying. It's there so you don't have a way bigger, more expensive failure later.

tara7932mo agoMost Upvoted

Ugh, it's like the whole world runs on cheap fuses now. My blender has a thermal cut-off that just gives up if you make too much smoothie. Same energy.

the_lee2mo ago

Yeah, the "cheap part that breaks on purpose" is the whole vibe now. @tara793's blender story is the same planned failure. It's good design for the company, bad design for my free time.