I need some ideas.

[RalphVa]

I'd rent an electric hammer drill. Then put a stud bolt in the bottom of your fence post into the hole you've made in the rock. This plus cementing around the fence post down to the rock should hold it in place.

I put in one of those safety pool covers about 3 years ago. I used my own hammer drill to drill the 4 corner holes. Took me forever and went through 2 drill bits.

I rented a huge hammer drill and was supplied with a concrete bit for it. I did all the other approximately 30 holes in less than 30 minutes. Using the proper equipment will save you lots of time.

Ralph

 

[texasjohn]

Thanks for the update...yep, where do you get one of these electric jackhammers??

 

[Just2quickz28]

There is this stuff called Dexpan that is a non blasting demolition foam. I have not used it but looks like it may work.
Dexpan Non Explosive Demolition Agent, Non Explosive Demolition Agent Dexpan, Dexpan Demolition No Explosive

 

[AndyMA]

Dexpan works great

Andy

 

[AndyMA]

Just an update of how I chose to go about getting these posts into the rock.

I bought this electric jackhammer and it went through layer after layer or dense rock like it was peanut brittle. The price of renting a gas powered unit was 150/day. This one cost me $175. It weighs in at about 50 lbs and can be beast to handle but it does what it says it will.

So how do we get one?

Andy

 

[pitt_md]

So how do we get one?

Andy

Andy,
I did a Google search for electric jackhammer and came up with many places that sell this same model. I got mine from this site. Industrial-Grade Electric Demolition Jack Hammer with 2 Heavy Duty Chisels | eToolscity

This is a Neiko model 2845. When I got it I checked the oil level and needed to add some. I took the plug out and the o-ring was dry and broken. I bought a new one from my local hardware store for $0.29 and everything was good to go.

 

[Baby Grand]

Low tech, slow but steady method:

1) Go to the store and buy beer & hotdogs - lots of beer.
2) Fill your FEL with water and park it right close to the rock.
3) Call some friends over.
4) Start drinking the beer - don't forget to share.
5) With your friends, clear out a 3 foot diameter pit over the rock.
6) Make sure to get all the soil off of the rock's surface.
7) Build a hardwood fire in the pit; right on top of the rock - the hotter the better - and keep it going. Remember - hot! Throw in coal if you have any.
8) Cook & eat the dogs.
9) Drink more beer.
10) After about 6 hours, when the beer is all gone and your friends start talking about leaving, dump the FEL full of water right into the fire pit. That should break up the rock down 6" or more pretty well.
11) Repeat as required until specified depth is achieved.

This worked for the Romans & it will work for you.

-Jim

 

[ultrarunner]

Andy,
I did a Google search for electric jackhammer and came up with many places that sell this same model. I got mine from this site. Industrial-Grade Electric Demolition Jack Hammer with 2 Heavy Duty Chisels | eToolscity

This is a Neiko model 2845. When I got it I checked the oil level and needed to add some. I took the plug out and the o-ring was dry and broken. I bought a new one from my local hardware store for $0.29 and everything was good to go.

I just ordered one... I will let you guys know when it gets here.

I've got a bigger Bosch that I don't use as much as I should because it's big and heavy...

 

[pitt_md]

I just ordered one... I will let you guys know when it gets here.

I've got a bigger Bosch that I don't use as much as I should because it's big and heavy...

I hope you get yours quicker than I did. I had it shipped standard ground and they gave me a 3 day window that it should arrive in. the last day of the "arrival window" was 9/23. I got mine on the 28th.

 

[Eaglebait Ranch]

Great Thread! I like what I have read. I am smiling because I have major, major hard pan at about 18". Really, really difficult to fence in pastures. But, I also have all the softball size rock anyone could dream of having. So, I clear the pastures of the rock and on the 10 acres of pasture I have (at last count) 67 rock jacks of about 30"-36" in diameter holding up "T" posts and corner posts. Any of you guys need any rock for rock jacks, let me know.