Gate Post Hole Through Rock
- Thread starter Obed
- Start date
- Views: 21139
OP
Obed
Elite Member
OP
Obed
Elite Member
OP
Obed
Elite Member
OP
Obed
Elite Member
Believe me, digging this pitiful little hole was really tough work. After 20 minutes of solid digging, I only penetrated the hard sandstone about 4 inches deep and 6 inches in diameter. I need to dig almost two feet deep through this rock and 12 inches in diameter. This digging bar isn't going to work. I'll never get my gate put up using this tool.
EddieWalker
Epic Contributor
I don't think you have sandstone. It looks like just sand that's very hard packed. There are no chunks of rock in your spoils pile.
I bet that a big masonary drill bit with an extension on it will cut right through it like nothing. Then with a few dozen holes around the edge and inside of it, the bar will break it up real easy.
The secrete to breaking up rock and hard materials is to have air around it. Concrete flat on the ground is very hard to break, but if you lift it just an inch, it breaks real easy. I think the same will be true for your hole. But since you can't lift it, you can create the space with a large drill bit. One inch or larger.
If you have a helper, you can also drill into it with the digging bar. I did this on a fence line in Northern California into a type of rock. We took turns holding and swinging the sledge hammer. The holder of the digging bar rotates it just a bit after every hit. In a short amount of time it will dig a good sized hole. Then dig another hole and another hole untile they start combining. It's allot of work, but it's doable.
Eddie
I bet that a big masonary drill bit with an extension on it will cut right through it like nothing. Then with a few dozen holes around the edge and inside of it, the bar will break it up real easy.
The secrete to breaking up rock and hard materials is to have air around it. Concrete flat on the ground is very hard to break, but if you lift it just an inch, it breaks real easy. I think the same will be true for your hole. But since you can't lift it, you can create the space with a large drill bit. One inch or larger.
If you have a helper, you can also drill into it with the digging bar. I did this on a fence line in Northern California into a type of rock. We took turns holding and swinging the sledge hammer. The holder of the digging bar rotates it just a bit after every hit. In a short amount of time it will dig a good sized hole. Then dig another hole and another hole untile they start combining. It's allot of work, but it's doable.
Eddie
slowzuki
Elite Member
- Joined
- Sep 19, 2003
- Messages
- 4,100
- Location
- New Brunswick, Canada
- Tractor
- Kubota L5030 HSTC, MF 5455, Kubota M120, Allis Chalmers 7010
Bah that stuff is terrible to beat at, it soaks up your blows. The suggestion to rent a rotary hammer is good, mine is a hmm, I can't remember but it blasted 54 holes, 3/4" diameter, 12" deep into 2 year old concrete including hitting lots of rebar in about half a day. Hitting rebar we would switch to the core drill then back. The core drill was probably over half the time spent.
You could have that hole chewed out quick even with a small bit.
The other option like they said is to use the same type drill to set anchors into the material if it is tough enough to pin a slab to it.
You could have that hole chewed out quick even with a small bit.
The other option like they said is to use the same type drill to set anchors into the material if it is tough enough to pin a slab to it.
KentT
Elite Member
- Joined
- Mar 31, 2005
- Messages
- 2,928
- Location
- Sevierville, TN
- Tractor
- 1993 Power Trac 1430 w/Kubota diesel engine
Eddie,
Having lived in Utah and Colorado in addition to Obed's general area, I can confirm that he has sandstone, and not just sand. In some areas it is just compressed more, making it harder than others. Some parts will break into chunks, some will crumble like sand. Remember also that the Appalachians in the Great Smoky Mtns, across the Tennessee River valley from Obed's place, are the oldest mountains in the world. This rock (if not basalt or granite) is "rotten" as it would be called in the Southwest. Even the slate and shale in this area often crumbles. However, there's marble mining and other commercial cut stone (called "Crab Orchard" stone) that's mined not far from Obed's area also... It varies widely in a pretty small geographic area.
For example, here's a pic from my property in the foothills of the Smokies where this tiny stream has eroded down to solid rock -- sandstone and shale -- and created little cascades all down the stream. This stone is so soft that if you hit either the shale or the sandstone with a hammer, it crumbles...
http://farm1.static.flickr.com/48/139506053_67ca5aad8b.jpg?v=0
Farther downstream, below the spillway for the lake my property is on, this is what these cascades look like. Look how round and eroded this solid rock is. There's also a bit less sandstone here, and more shale. The shale is finer grain and is a bit harder -- but not a whole lot. This whole area was seabed, many, many millions of years ago, and is sedimentary. Some areas only 30-40 miles away is pure limestone, where underwater streams, caverns and artesian springs are common. Only along the spine of the Appalachians did the crust buckle, bringing granite and basalt closer to the surface. In the many millions of years since, all the sandstone, shale and softer rock has eroded off those peaks, which will now expose the granite and basalt. Alabama, Mississippi and Louisiana are likely what's left of what eroded off those mountains -- and on the other side of the watershed the same can be said for the rolling plains of North and South Carolina...
http://farm1.static.flickr.com/32/62619925_2ff7c74db6.jpg?v=0
Obed -- I think you can drill what you need to drill with a big hammer-drill and not a jackhammer. A jackhammer would just turn it into sand and pound the sand...
Having lived in Utah and Colorado in addition to Obed's general area, I can confirm that he has sandstone, and not just sand. In some areas it is just compressed more, making it harder than others. Some parts will break into chunks, some will crumble like sand. Remember also that the Appalachians in the Great Smoky Mtns, across the Tennessee River valley from Obed's place, are the oldest mountains in the world. This rock (if not basalt or granite) is "rotten" as it would be called in the Southwest. Even the slate and shale in this area often crumbles. However, there's marble mining and other commercial cut stone (called "Crab Orchard" stone) that's mined not far from Obed's area also... It varies widely in a pretty small geographic area.
For example, here's a pic from my property in the foothills of the Smokies where this tiny stream has eroded down to solid rock -- sandstone and shale -- and created little cascades all down the stream. This stone is so soft that if you hit either the shale or the sandstone with a hammer, it crumbles...
http://farm1.static.flickr.com/48/139506053_67ca5aad8b.jpg?v=0
Farther downstream, below the spillway for the lake my property is on, this is what these cascades look like. Look how round and eroded this solid rock is. There's also a bit less sandstone here, and more shale. The shale is finer grain and is a bit harder -- but not a whole lot. This whole area was seabed, many, many millions of years ago, and is sedimentary. Some areas only 30-40 miles away is pure limestone, where underwater streams, caverns and artesian springs are common. Only along the spine of the Appalachians did the crust buckle, bringing granite and basalt closer to the surface. In the many millions of years since, all the sandstone, shale and softer rock has eroded off those peaks, which will now expose the granite and basalt. Alabama, Mississippi and Louisiana are likely what's left of what eroded off those mountains -- and on the other side of the watershed the same can be said for the rolling plains of North and South Carolina...
http://farm1.static.flickr.com/32/62619925_2ff7c74db6.jpg?v=0
Obed -- I think you can drill what you need to drill with a big hammer-drill and not a jackhammer. A jackhammer would just turn it into sand and pound the sand...
OP
