Limiting depth of post hole digger

[LS Tractor Owner]

I remember that red shale when I lived in Bucks Co, Pa. You would have a hard time going just a few inches without hitting it. Been thrown off of a two man auger in that stuff!:laughing:

I'm not kidding that there are no rocks in my soil here. My property is about 3/4 mile from the base of a mountain, which is just about all rocks. When I dug our septic, went down 6 1/2' and not one rock.

The tip on the auger is about 6" long, a tight spiral from about a 1/2" up to 2 1/2" . This thing just immediately digs and screws itself in about 6" almost within a second or two (pretty much reaction time to lift it back up). The first "dig", I was able to lift the auger and clear the dirt. The second time back down the hole for the next 'bite', it just continued to dig in, maybe I took too long to lift.

As for the 'drop rate valve', I haven't adjusted that nor was I using it, only the 3 point lever. The auger doesn't walk or move from where it is placed, it just immediately screws itself in. Digs straight down.

Didn't get a chance to play with it again today. Hopefully tomorrow, using some of the tips from here. I'll post my escapades afterwards....wish me luck.

 

[LS Tractor Owner]

Clarification,
Bought Stihl drive head and two augers, used from rental yard $200.
White RS Hyd motor, 2 hoses, power beyond valve next to loader valve $ $300.
Misc iron in shop, simple frame, short pieces 2 x 5 tube to slide over pallet forks. Hardly a huge investment. To date, 400+ fence posts installed

Out here the rental yards charge crazy prices for the used and abused equipment. There is just about nothing available in a two hour radius... And I mean nothing more than a lawn tractor or chain saws. About the only equipment is very large mining equipment. If you want a good laugh, just go on Craigslist in Albuquerque....pretty much junk only. Sorry to be a little testy earlier...

 

[BrokenTrack]

Out here the rental yards charge crazy prices for the used and abused equipment. There is just about nothing available in a two hour radius... And I mean nothing more than a lawn tractor or chain saws. About the only equipment is very large mining equipment. If you want a good laugh, just go on Craigslist in Albuquerque....pretty much junk only. Sorry to be a little testy earlier...

Someone mention using a post hole drill to make fence post holes and that should NEVER be done. Frost action will pull the post back out because the soil has been loosened on the sides of the posts. Fence posts should ALWAYS be driven into the ground.

Most of the time I use my backhoe on my log trailer to dig posts because rocks do not stop that, but I can install a post hole drill on my log trailer too. Because my grapple rotates in either direction, 360 degrees, I can swing my log loader around and bore a hole, and if it gets jammed, just back it out by reversing it. This works really good, so for people who want to do a lot of post holes, a post hole driller on a boom is a much better choice.

 

[Fallon]

Post pounders dont work here in Colorado. The clay is to hard & posts just break, even if you are in an area with no rocks like me. I haven't tried personally but have heard that from my dealer (he won't sell em) and a few others that have tried them over the years. I was keeping an eye out on Craigslist for em for a while & saw 3 in as many years, 2 of which were at least 1 state away.

I've had no issues with my posts coming loose in the 4 years since I put in the first new fences. I tamp them in hard in 6" lifts though.

When I pulled the old posts I couldn't tell the difference between the 1/3 of them th as t were cemented in vs ones in dirt until they were out of the ground. I'd either see the cement on the post or sometimes a cement hole in the ground in front of the tractor. There were several old posts I couldn't pull with my L3200 (1,200lbs rated lift, probably several hundred lbs more actually & I was pulling with the back of the bucket for better lift geometry). Several of those broke trying to wiggle them out. The ones of those I checked were not in cement. Those posts had been in for years if not decades.

 

[buickanddeere]

I have only used one or two man augers in the past, this is my first 3 pt PHD. I have watched numerous videos and read numerous posts. I thought I was well prepared to dig my first hole....wrong. I'm using a 9" auger, standard length. Tractor is a 25hp SCUT.

I had the throttle about 22-2300 rpm, dropped the 3 pt a little and the auger dug right in. I lifted it after approx 6-8 inches in, lowered it again trying to do the same, but it screwed in about 8-10 inches. When I immediately tried lifting, but it just stalled the tractor. Restarted the tractor and tried at full rpm at 3000. It just continued to dig in. When it went to full depth, (couldn't go any further, gear box at ground level), it just excavated all the dirt and freed itself up, about a full 48" deep.
The dirt is very dry clay, no rocks or roots at all. I was actually surprised at how easy it screwed into the ground.

I only have to go 24" (30" max) deep on the holes so, my questions:

1) Can I set up a mechanical stop on the 3 point lever to only lower the 3 point to a predetermined position or will the auger continue to just pull it down? I'm hoping that once it hits that "stop point", the auger would just free itself up like it did in the first attempt.
2) What throttle setting should I use? It seemed that at a lower throttle setting, it didn't dig in as fast, but I had no power to lift.
3) I have looked at purchasing a "compact" auger which is only 32" long, but really don't want to spent $140 for another auger if question #1 would work.

Any help would be very much appreciated. Thanks

Why are you operating the engine at max throttle while auguring ? That is a recipe to quickly get into trouble . Idle and just feed it a little depth at a time or she will get away on you.

 

[buickanddeere]

I have never seen frost push a fence post from the soil .

 

[TerryR]

The first "dig", I was able to lift the auger and clear the dirt. The second time back down the hole for the next 'bite', it just continued to dig in, maybe I took too long to lift.

"Lifting" is the problem. You shouldn't have to lift. Rather drop the 3-point just a little bit at a time. Nudge the lever downward just a little each time. And of course as others have said, keep the engine RPMs low.

 

[rademamj]

Same as my experience. My very first attempt along a fence line with the 3-point post hole digger buried the 12" auger to the gear box. After 1 hour effort, finally got extraction of the auger and did a shear pin replacement. It became very clear to me that soil type was critical.

1. Hard moist clay will almost always bury the auger. Need to auger down slowly and constantly lift every 3 inchs to clean out the hole. Using this method; about 1 in 5 holes still will bury to the gear box.

2. Sandy soil or sandy loam, never seem to get stuck. Holes go down in 5 mins and every one of them an easy success. Sandy soils make you look like an instant expert. Never get stuck. 3pt easily lift out of the hole everytime.

Layered soils are most challenging. These may have 1-3 feet of sand over top deeper clay. The sand augers easily....and then ZOOM...you hit the clay and buries the auger quickly. Clay soil is your enemy everytime.

 

[rademamj]

Same as my experience. My very first attempt along a fence line with the 3-point post hole digger buried the 12" auger to the gear box. After 1 hour effort, finally got extraction of the auger and did a shear pin replacement. It became very clear to me that soil type was critical.

1. Hard moist clay will almost always bury the auger. Need to auger down slowly and constantly lift every 3 inchs to clean out the hole. Using this method; about 1 in 5 holes still will bury to the gear box.

2. Sandy soil or sandy loam, never seem to get stuck. Holes go down in 5 mins and every one of them an easy success. Sandy soils make you look like an instant expert. Never get stuck. 3pt easily lift out of the hole everytime.

Layered soils are most challenging. These may have 1-3 feet of sand over top deeper clay. The sand augers easily....and then ZOOM...you hit the clay and buries the auger quickly. Clay soil is your enemy everytime.

After reading previous comments; I would clarify the post holes being drilled are for 8 feet long 8" diameter treated wood posts spaced every 60 feet and set in concrete at 30" depth. Fence steel end posts are also drilled and set into concrete. T-posts are set every 10 feet, and these pounded 30" deep using a Rhino fence post driver. Each T-post takes 3 minutes to drive to proper depth independent of the soil type. The fence is typical 60" field fence. I run a single string of barb wire at top of the field fence.

 

[Tx Jim]

1. Hard moist clay will almost always bury the auger. Need to auger down slowly and constantly lift every 3 inchs to clean out the hole. Using this method; about 1 in 5 holes still will bury to the gear box.

Layered soils are most challenging. These may have 1-3 feet of sand over top deeper clay. The sand augers easily....and then ZOOM...you hit the clay and buries the auger quickly. Clay soil is your enemy everytime.

Having PH digger auger corkscrew into soil will not happen if tractor operator eases 3 pt control lever forward in small increments with engine at 1200 rpm's(little ABOVE IDLE) not matter what type of soil one is attempting to drill a hole into.