# Digging Post Holes in Hard Ground / Rock



## YuccaFlatsRanch (May 3, 2004)

I am in the process of digging T-post holes in some mighty hard caliche / Limestone rock.

How am I doing it - I just bought a Dewalt DW 25551 Rotary Hammer Drill on Ebay to drill T-post holes using a 1 1/2 in diameter Carbide bit. This is an 11 amp drill that will drill using up to 5 inch core bits in concrete. You can find them on Ebay by doing a search for Rotary hammer Drill. Bosch, Hilti, Hitachi, etc are other brand names for these BIG drills.

The drill allows me to put posts where I WANT TO vs where the rocks want me to.


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## Kazahleenah (Nov 3, 2004)

Must be nice!! We're hand digging holes for cedar posts.... and keep running into gravel and rocks... 

Kaza


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## Ramblin Wreck (Jun 10, 2005)

Sounds like a neat solution considering your limestone challenge. We've been "mashing" most of our t-posts in with a loader, but when we hit rock, unless we're quick to back off the pressure, we fold the post in half.


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## uncle Will in In. (May 11, 2002)

With such tough places to dig the holes, it would be easier to just buy the holes at the farm store.


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## CGUARDSMAN (Dec 28, 2006)

do you have a rock bar??? they are invaluable for what you are doing!


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## comfortablynumb (Nov 18, 2003)

in some places here we use an electric bocsh jackhammer.


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## CJ (May 10, 2002)

My laptop thanks you for the water bath...LOL   



uncle Will in In. said:


> With such tough places to dig the holes, it would be easier to just buy the holes at the farm store.


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## big rockpile (Feb 24, 2003)

Once again I've put Fence in about every kind of ground you can think of and I've never dug a Post Hole other than Corner Post and I don't have to do that here. :shrug: 

Just seems like a lot of work but more power to you.

big rockpile


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## brosil (Dec 15, 2003)

We have to buy our rocks and haul them in.


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## YuccaFlatsRanch (May 3, 2004)

"In some places here we use an electric bocsh jackhammer."

A jackhammer is much the same as the rotary hammer drill, just bigger yet. I drill the holes because I want a hole of a certain diameter (1 1/2 inches) by a certain depth (about 14 inches) to hold the T-post securely. Buying the drill on Ebay cost me $200.00 and the bit was about $60.00 with shipping. I already have a friend who will buy them from me when I am done with my holes. Therefore my net cost is zero.


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## Joy in Eastern WA (May 10, 2002)

Just bought one of these....
http://www.belltec.net/post_hole.html
We have acres of solid rock and broken bassalt, so, in order to get a good fence up, we decided to take the plunge and invest in one. Those hammer drills would do me in well before I even got started!


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## YuccaFlatsRanch (May 3, 2004)

Great machine but pricey!!!!! For my corners it was much easier to hire a guy with a bobcat and a rock cutting auger. 50 fence post holes cost me $130.00.


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## Rae Jean (Sep 23, 2007)

I've done that before and I'm doing it now. It makes a great workout.


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## busybee870 (Mar 2, 2006)

i dont believe anything you said about that new drill, bring it over here and show me. if you can drill about 24 holes in my bedrock without any trouble ill believe you!!


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## WindowOrMirror (Jan 10, 2005)

How much for that fancy thing Joy?


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## Joy in Eastern WA (May 10, 2002)

WindowOrMirror said:


> How much for that fancy thing Joy?


Too much!  But, with having to dig at least 500-700 holes on this ground and a high percentage of them in rock, it was much cheaper to purchase this machine for $6k than pay someone $50 bucks a hole.
Maybe we can even get a little bit of our cost back by drilling some holes for our neighbors!


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## texican (Oct 4, 2003)

Yucca...

Are your rocks getting out?  I had a 'discussion' with a rich neighbor a few years back... he wanted me to help pay for half of a useless fence... I told him my pine trees very rarely wandered off... and if any did, I'd be glad to pay for whatever damages they might cause... So I was justa wonderin, if the ground is so hard you have to drill holes for your tposts, what you were fencing in, or fencing out...

If your ground is that hard, I take it your fencing for goats?


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## fordy (Sep 13, 2003)

................Even the Bel Tec augars won't dig in very hard rock as well as some might think . I've watched them dig down a few inches and then just quit digging because the cutting teeth needed to be sharpened . I suppose the electric hammer drills might be somewhat effective but for real hole drilling authority there is only one machine .....i.e. the rotary Air Hammer drill and an aircompressor to power it . We knocked the face plates off the Tposts and used the 1.5 inch bit . It takes Big Gonadista's too run one of these air powered rotary hammer drills and most folks under 250 pounds have a hard time keeping the drill in the correct spot . lol , fordy


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## Shinsan (Jul 11, 2006)

uncle Will in In. said:


> With such tough places to dig the holes, it would be easier to just buy the holes at the farm store.


Army surplus stores are great too; buy a large bomb crater that can be sliced up in to several smaller holes. Left-over pieces can be minced finely into tiny holes that can be glued together with rubber compound to make irrigation hoses.


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## YuccaFlatsRanch (May 3, 2004)

"So I was justa wonderin, if the ground is so hard you have to drill holes for your tposts, what you were fencing in, or fencing out..."

Sheep and goats and an occasional steer. Fencing out predators and deer.

"i.e. the rotary Air Hammer drill and an aircompressor to power it . We knocked the face plates off the Tposts and used the 1.5 inch bit . It takes Big Gonadista's too run one of these air powered rotary hammer drills and most folks under 250 pounds have a hard time keeping the drill in the correct spot . lol , fordy"

The electric rotary hammer drill is a smaller cousin to the big rotary. I have limestone and hard caliche which don't require heavy construction equipment, yet do require the holes drilled. If I don't drill the holes then the rocks determine where my posts go. This way I GET TO DECIDE where they go. Otherwise, we do it the same as you posted.


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## WindowOrMirror (Jan 10, 2005)

I wonder how the Bel Tec would do in the following two circumstances?

1: Dirt and field stone
9"-12" auger in dirt with field stone ranging in size from 2" to 14" regularly getting hit.

2: Solid Blue slate
We're at the edge of an old morraine and occasionally have to dig through solid slate (ouch)


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## fordy (Sep 13, 2003)

WindowOrMirror said:


> I wonder how the Bel Tec would do in the following two circumstances?
> 
> 1: Dirt and field stone
> 9"-12" auger in dirt with field stone ranging in size from 2" to 14" regularly getting hit.
> ...


...............Bel-Tec will work very well where the subsurface rock is fractured , as the auger will leverage one piece against another and simply fracture them into smaller pieces and maybe even auger them out of the hole . OTOH , if drilling in a basically unfractured layer of something very hard I'm afraid that the hardened cutting tips will shortly become dull and need REsurfacing and sharpening . 
................I'd go rent a Bel_Tec digger from a rental place and actually try it on your tractor , OR just rent a tractor with one already installed BEfore purchasing one and then finding out it isn't up too the job . , fordy


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