Posthole Digger Post hole digger - Medium or Heavy Duty - plus auger size

[Texasmark]

I run a 12" with a Ford 3000D, Live PTO. Hp really isn't the requirement; being able to pull it out when you stick is. I live in clay soil and it varies in moisture from the top down, depends on how long since and how much rain has soaked into the ground.

I run a low rpm (aka no need for a lot of hp) and the reason for that is that it gives you time to react to what's happening. When in hard soil it grinds and grinds and you get no where. Pouring water in the hole helps. Putting weight on the digger helps also.

In soft soil it wants to run away with you. I make a habit of up and down, taking a little bite and coming up, not out, up; keep working the height taking small bites so that your hand is already on the lift and your brain is already acclimated to coming up right after you went down.

If it takes off fast on you, just push in the clutch if Live or Transmission PTO. If independent, have you hand on the OFF switch.

When at the bottom of the hole, switch the PTO off with the auger full of "loose" material. Lift the auger out of the hole and hit the PTO for a second to throw the "finds" out and away from the hole.

If you get stuck, take a pipe wrench and a cheater bar with the PTO disconnected if necessary and grasp the auger shank just above the blades and manually just "unscrew it". You shouldn't have to go all the way out. Just enough to the point where the lift (PTO still off or disconnected) will pull it out of the hole.

The digger is light duty if anything and I have had it for about 30 years. Just sits out in the weather till I need it. Hook to it, dig the hole and put it back.

I work alone so I have a damaged 6" auger that I augered about half way into the ground. When storing, I take the 12" off and back up to that one and drop it in the hole then disconnect from the tractor. Some folks hang theirs from playground swing A frames. Having it on the ground or on a pallet/skid, is just a lot of trouble.

Be sure that you watch the auger gearbox pivot vs the boom pole. That gearbox will pivot till it touches the pole. If you finger is in there it will be a big OUCH.

Want more, ask.

 

[bdog]

being able to pull it out when you stick is

When in hard soil it grinds and grinds and you get no where.

Putting weight on the digger helps also.

if necessary and grasp the auger shank just above the blades and manually just "unscrew it".

These are perfect examples why you should chose a hydraulic loader mounted PHD. They are expensive. I know. I bought mine in 2010 and my rationale at the time was I will put up the coin for this now, do my major fencing project, and sell it when done. It has been so useful over the years I still have it and have used it so much. Just this year I have already dug over 50 holes and am going to dig 10 deep ones on Monday.

Maybe in some locations a 3pt digger works but around here using one is like a kick in the nuts.

 

[YardBikeBob]

I believe Texasmark is on the mark.

I run a PHD much like you're considering and have only a 12" auger. You mentioned sandy/clay soil but nothing about rocks. My soil is clay with rock. I've drilled several dozen holes over the years. My observations:

A half bucket of water does wonders when drilling through hard clay.

You really must have a digger pole. A 20lb, 6' long metal rod with a point on one end and a mushroomed tamper on the other.

A 12" hole is just wide enough to angle the digger pole into when breaking up rocks. I would think a 9" hole would be too narrow.

Some PHDs have a welded ring on the top and some folks use that to wedge in the digger pole and lean into it for more downforce. I haven't found that very useful. Normal downforce is a few hundred pounds of the PHD, what can you add to that? Nets a bent digger pole and not much faster digging.

A 12" hole is about the right width when burying 6" posts. The extra diameter is needed to tamp down small rocks and/or pour concrete around the post to steady it.

I question the value of a slip clutch over a simple shear pin on a PHD. When the auger bit hangs, it will stop the drill right now. Shearing a common bolt is cheap and protects the machine. A screaming slip clutch would seem overkill. Also, a slip clutch is another thing to service as they will rust shut over time.

I have independent PTO driven with 30hp. But I rarely dig more than a few 100 rpm over idle. This has seemed more productive. So this isn't a high-hp task.

All the talk about hydraulic down force PHDs and FEL mounted PHDs make them sound common. I've never seen one here in the county other than Gov't or utility companies -- normal folk seem to have more time than their own money.

Drilling one good hole takes a few minutes or a few hours depending upon what you find down there! The former is rare and cause for celebration.

~Bob

 

[bdog]

Some PHDs have a welded ring on the top and some folks use that to wedge in the digger pole and lean into it for more downforce. I haven't found that very useful. Normal downforce is a few hundred pounds of the PHD, what can you add to that?

All the talk about hydraulic down force PHDs and FEL mounted PHDs make them sound common. I've never seen one here in the county other than Gov't or utility companies -- normal folk seem to have more time than their own money.

Drilling one good hole takes a few minutes or a few hours depending upon what you find down there! The former is rare and cause for celebration.

~Bob

Downforce is everything when digging. Aside from digging postholes I also have a rig which digs 3.5" holes for dynamite shot holes. These vary from 10-100' deep. Even on the ten footers we sometimes apply over 1000lbs of downforce and it makes all the difference in the world. More downforce equals faster digging.

On my 3pt digger when I had it I welded about 300 pounds of weights on it and it helped but was nothing compared to hydraulic downforce. A few hundred pounds is not enough downforce particularly with large augers. Drilling a fence post hole shouldn't take more than 5 minutes unless you are in solid rock. Around here we have zero rock for hundreds of feet deep. With my hydraulic digger it takes me longer to position than to dig the holes. With 3 point I have spent 30 minutes on a hole even with adding water.

Hydraulic augers are not that expensive. I think I paid $1500 for mine with the SSQA plate, the motor, and a 9" bit. that was 9 years ago not sure what they are now but they are priceless. I could literally drill hundreds of holes a day vs maybe 25 a day I could get with a 3 pt fighting my way with each one.

 

[YardBikeBob]

Downforce is everything when digging. Hydraulic augers are not that expensive. I think I paid $1500 for mine with the SSQA plate, the motor, and a 9" bit. that was 9 years ago not sure what they are now but they are priceless. I could literally drill hundreds of holes a day vs maybe 25 a day I could get with a 3 pt fighting my way with each one.

I actually agree with everything you say. If I wanted the capability to drill 100's of holes a day, and get paid for it, that would be the ticket. But the OP was a hobby weekend farmer.

Then again, who can really believe in a fella who lives in a world without rocks.

~Bob

 

[bdog]

I do not dig post holes for hire. All the ones I have dug have been on my own place for my own fencing and building needs. We have more land than this but all the fencing we have done has been on about 7 acres. It has perimeter fencing and multiple cross fences, fences around the house, pond, shop, etc all with 2-3/8" pipe set on 8' centers. Lots of holes. I am a homeowner who originally bought a 3pt for my own use and was so frustrated with it I sold it and bought a hydraulic. I guess everyone's situation is different and the 3pt versions must work well in some parts of the country or they would not be as popular as the are because they are about useless around here. Time is money and while I don't need things done super fast I don't want to spend five hours digging ten holes.

I hate to sound like a broken record but of all the implements I have ever owned or currently own the 3pt auger was the one I was most disappointed in and at the same time the hydraulic is amazing. Night and day difference - here. Maybe not everywhere. Just this afternoon I drilled 5 holes 18" in diameter 5' deep in about 30 minutes. These are for the columns for the shed I am building for my attachments.

 

[Texasmark]

These are perfect examples why you should chose a hydraulic loader mounted PHD. They are expensive. I know. I bought mine in 2010 and my rationale at the time was I will put up the coin for this now, do my major fencing project, and sell it when done. It has been so useful over the years I still have it and have used it so much. Just this year I have already dug over 50 holes and am going to dig 10 deep ones on Monday.

Maybe in some locations a 3pt digger works but around here using one is like a kick in the nuts.

Commercial guys that build fence around here use a Bobcat front mounted hydraulic digger...may be what you are referring to, to do their digging. Definitely superior to a 3 pt AND you can see what you are doing much easier.