Digging post holes in hard clay?

[jerp]

I'm extending a fence and need to dig a few post holes. Because we have just a few inches of topsoil over clay I rented an auger. (the days of using manual diggers for more than one hole are behind me) Anyway, the auger will not even dig through this stuff. I guess after several years of drought the clay has dried up to resemble concrete. I leaned on that auger for 30 minutes and all it did was go down a few inches then sit there and "polish" the clay. Any ideas? I would like to avoid hiring someone with a tractor mounted auger to drive into my yard if possible. I thought about soaking the ground but I don't know if I could ever get it to take enough water to soften 24" deep.

[Rangefinder]

What we have to go sometime is put water in the hole At the same time as u r digging it.

[HELLRAZOR]

Make sure the auger tip aint burned out....ive been in ur shoes a couple of times.....if not mark all ur holes start all of them then add water and come try them again later!...good luck partner

[tex4k]

Forget the tractor hire an auger truck, (the ones used to set power poles), like you, I've outgrown hand diggers. My sons business has a couple of these trucks, only way to dig post holes out here in caliche country. The best part is, him moving from hole to hole will be the longest part of the job.

[postman]

get the hole started. fill with water. wait till next day. dig what you can. repeat. slow but will work.

[black dallas]

like said above, short of hiring a bobcat with auger(awesome!!), dig what you can, water, and come back later. or a rock bar, i got one if you can run it all day!!

[M.E.B.]

Thinking out loud: do you have a power washer?

[curtintex]

Thinking out loud: do you have a power washer?

Hydro-excavation….it works extremely well.

[Atfulldraw]

Hydro-excavation….it works extremely well.

Water is your friend!

[Boomerang]

If it is just clay, your blades or tips could be dull as mentioned. There isn't any reason why it won't cut through that. Granted it is hard, but not like rock or limestone. Water will help but sharp new blades are going to cut wet or dry.

[Bigboss]

Auger...rock bar. .water soak..repeat

[TxNurse]

If you are hitting rock, a rock drill run off of a high volume low pressure compressor will do it easily. Usually about $100/day to rent.

[MASTERS]

We have a bobcat with an auger atrachment that will dig through most anything from 9" to 14" holes. If need be we put on the rock bit.

[Boyd1212]

Hydro-excavation….it works extremely well.

I run a hydrovac truck and I have come across some clay that we couldn't even cut through, and 4500psi is a lot of pressure.
If you try to use the pressure washer idea, get a turbo nozzle for it. That is what we use to dig.

[banzai]

Rent a Bosch Brute 110 volt jack hammer. Hopefully you can get the spade bit in addition to the standard straight bit.