Posthole Digger Quality of Gear Box questions

[RoyJackson]

I think you'd do more expensive damage using a 60 hp gearbox on a 24 hp tractor than a tractor and gear box that are equally matched. The big gearbox is going to have a big shear pin and the way smaller rated tractor pto is going to be the weak link. If you're going to do something like that you need to get ahold of the manufacturer or an engineer to figure what size/grade shear pin to use for 24 hp.

Any Category 1 implement that is shear pinned will be (relatively) safe, no matter the gearbox rating, although there have been tractor PTO's damaged on occasion. Main thing (IMO) is to stick with the grade of shear pin the manufacturer specifies.
Another thing, again IMO) is to engage to PTO at a low RPM (I used about 1000-1200 with a bit of foot throttle, if necessary) to reduce the shock load on the tractor.
Katesaidan's (the OP) has stated their property is pretty rocky, so I'd expect they'll want plenty of spare shear pins and know how to replace them.

BTW, since PTO's don't reverse, you'll want a pretty good size wrench to back the auger out if and when it gets stuck.

 

[bigbull338]

well now if its real rocky a reg posthole digger wont cut it.the best thing is a bell tech hydro 3pt posthole digger.

 

[HiTechTed]

Any Category 1 implement that is shear pinned will be (relatively) safe, no matter the gearbox rating, although there have been tractor PTO's damaged on occasion. Main thing (IMO) is to stick with the grade of shear pin the manufacturer specifies.
Another thing, again IMO) is to engage to PTO at a low RPM (I used about 1000-1200 with a bit of foot throttle, if necessary) to reduce the shock load on the tractor.
Katesaidan's (the OP) has stated their property is pretty rocky, so I'd expect they'll want plenty of spare shear pins and know how to replace them.

BTW, since PTO's don't reverse, you'll want a pretty good size wrench to back the auger out if and when it gets stuck.

Man I never even thought of that...I'm going to get a post hole digger myself soon. Good info!

 

[inveresk]

I'd also buy at least one spare set of teeth when you get your phd. I find I get about 80 posts drilled in our rocky soil before I have to replace them.