3pt hitch PHD (post hole digger) are nice, so much better than hand digging that is for sure.
there are issues though....
--you may end up getting down force kit for the PHD, to help make holes at ugly times of the year when soil is dry / hard and compacted. you do not have to have a down force kit, and use the old water in hole and let set for a half day to a day. to get hole dug. but..
--if you get auger down into a root. there is no "reverse" so ya out there with a pipe wrench, twisting it back out.
--a tractor is not the most agile of units out there. and can be rather tricky trying to backup or move forward, etc... just that 1/2" and hold on brakes etc... to keep from moving as you operate the PHD.
--as PHD digs, it goes in at an angle.
--can be rather hard to see around tractor even if you have a second person there spotting you.
with above...
--are you hand tamping the dirt back in around the posts? to keep them aligned? the hand tampers need a little bit of wiggle room. granted to much wiggle room and ya there constantly tampering more dirt than needed.
--if you are tossing in some concrete into the bottom. ok hand tamping not as much but still.
--if you are running fence along property line. or want a nice straight line, you will either hit some ugly spots were ya break out spade, and the old 2 handle manual post hole digger. or go for a bigger auger bit. so you can adjust the post over this way or that way.
a 3pt hitch PHD is fairly cheap. and kinda hard not to buy one, if you need to put in some fence.
but....
--renting a mini ex (mini excavator) with a PHD instead of a bucket on it. might be something, or if you have a backhoe, swapping the bucket out for a PHD. these PHD diggers run off of hydrualics, so there is both a forward and reverse. so if ya do get auger stuck under a root for example. move the hyd lever back. and away you go. plus you have down force already there. and abilty to line up PHD level and in line with rest of posts fairly easy.
--and then there is... post hammers. either a railed sledge kinda of hammer that attaches to a tractor, or fork lift unit or like. or a post hammer that uses pressurized air, or an mini explosion (shot gun shell in a sense) to hammer the posts into the ground, without drilling a hole and no need to tamp any dirt back around the post.
--post hole digger or hammer mounted to a FEL (front end loader), might be an option.
--and then the ugly 2 man post hole digger (2 cylinder (weed eater engine)) that a couple guys run. you can rent one man units but not really made for large deep holes.
i am for a backhoe or a mini ex approach.
--the fence lines here run 1 T metal, 1 4x4 wood, 1 T metal, 1 4x4 wood,etc...
the T posts, i stab into the ground by hand, and then use the backhoe bucket, to push them down, ya need around 1 to 1 1/2" short pipe welded onto backhoe bucket. so end of T post does not slid away from you and cause the T post to bend. if you have a small say 6" to 9" bucket for backhoe or mini ex. dig the holes perpendicular to the fence line. so the fill dirt going back in. does not go in direction of the fence. but away from the fence.
--open up the old phone book, and look up "equipment rental" or "machinery rental" call a few places a couple hours away "prices can be that different". and see how much it is to rent. fence lines last for a long time or at least they should. see what it costs to rent vs buying.
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i don't set that many corner posts. compared to actual line posts. so 6" auger for a 4x4 works good enough for me. on other hand a 9" auger would be nice for 6x6 corner. but honestly i save more time dealing with the 50 plus wooden line posts. vs the handful or corner posts i would need to deal with.
