What to dig post holes with in rock?

[Gomer pyle]

I have a JD5090E tractor. I'm trying to find the right attachment to dig my post holes. I hand dig most of mine but I'm unable to get some down due to solid rock, TN blue limestone. I know it's probably better to get a rock drill and jack hammer but, due to a back injury, I can't run the jack hammer due to vibrations. Looking at different things online, the Belltec TM-48 looks like it would possibly be the best option but it is out of my price range. How well do the hydraulic skid steer mount augers do? My tractor's flow is around 17gpm, which would pair best to my machine? I would like to get something to dig all my holes from now on.

 

[2manyrocks]

One of my friends in middle TN rented a rock drill which I believe was track driven. Nothing else would bore through the layer of limestone on his farm.

 

[gsganzer]

I have a JD5090E tractor. I'm trying to find the right attachment to dig my post holes. I hand dig most of mine but I'm unable to get some down due to solid rock, TN blue limestone. I know it's probably better to get a rock drill and jack hammer but, due to a back injury, I can't run the jack hammer due to vibrations. Looking at different things online, the Belltec TM-48 looks like it would possibly be the best option but it is out of my price range. How well do the hydraulic skid steer mount augers do? My tractor's flow is around 17gpm, which would pair best to my machine? I would like to get something to dig all my holes from now on.

SDS-Max drill might get you there. The thing with the rock soil, you don't need to dig near as deep to secure a cemented post.

On my clay soil, I sink a post at least 3 feet deep in a 9" cemented hole. If I hit limestone, I'll SDS-Max a smaller diameter hole to 2', set the poll in cement and call it good.

 

[Hay Dude]

I use an iron post spade.

 

[RjCorazza]

I have a Land Pride ssqa auger that would work with that hydraulic flow available. Rock bits are available, but I suspect they are not cheap.
The down pressure makes a big difference in rocky soil (not talking solid rock layer) with a regular auger.

 

[M59]

What size and shape ( dia or x by y dimension) posts are you trying to plant and how deep do you go before you hit the TN blue stone?

Rock augers are available and work very well in the softer stone or ground littered with hard stone. I prefer running the hydraulic driven auger off the SSQA and using the 3rd function because I can back the auger out of a jam.
Pic of rock auger with carbide points and hard facing along flight edges.
Pic of Mcmillen X1475 that I run on the M59. Loads of down pressure ( close to 5,000 Lbs) when front wheels off ground.

 

[Gomer pyle]

One of my friends in middle TN rented a rock drill which I believe was track driven. Nothing else would bore through the layer of limestone on his farm.

That doesn't really work for me because I need to do a few here and there. But yes, that is the best option to get the job done

 

[Gomer pyle]

I use an iron post spade.

I'm not sure what that is

 

[Gomer pyle]

What size and shape ( dia or x by y dimension) posts are you trying to plant and how deep do you go before you hit the TN blue stone?

Rock augers are available and work very well in the softer stone or ground littered with hard stone. I prefer running the hydrualic driven auger of the SSQA and using the 3rd function because I can back the auger out of a jam.
Pic of rock auger with carbide points and hard facing along flight edges.
Pic of Mcmillen X1475 that I run on the M59. Loads of down pressure ( close to 5,000 Lbs) when front wheels off ground.

8-9" posts. Some of mine start rock on top of the ground, some are a foot down before it starts.
I have rented skid steer augers when I have a few to do and like it. All the ones I've rented have dirt augers. I just want to make sure that one will do the job before I invest that much money

 

[bcp]

Several years ago I watched a school construction. They poured concrete steps. Some time later handrail posts were installed by core-drilling about 2.5-3. inch holes, with a large hand-held drill, maybe air powered. Then the post was "glued" into the hole, with a smooth gray substance, maybe epoxy.

Maybe you could do something similar using T-posts.

Bruce