[NA]Rock Drill use[NA]

Let'sgoflying!

Let'sgoflying!

Touchdown! Greaser!
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west Texas
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Dave Taylor
I have about fifty 1&1/4" holes to drill into volcanic rock. (t-posts for a fence)
I can rent a hand held rock drill with a diesel-driven compressor to do the drilling.
Since I made this plan I hear a couple of local stories of the thing busting arms and hands so I am rethinking the project.
There is no one around to hire this out.

How to be safe about it?
If the bit binds in the hole, its like an electric drill except with a whole lot more torque. The drill motor starts to spin I'd presume and that's where the trouble starts. I looked at the drill and it's a T shape, with about a 20" handle on the top; ie 10" on each side of center.
I thought, 'I will put extensions on that and have two guys hold it' but I think even with six foot extensions they probably could not hold it and it would start spinning like a propeller, killing us.

Anyone ever used one of these things? What are some ways to stay safe? Don't they have an autoshut-off so that if it gets out of hand it pops off the pressure?
 
Is it like a jackhammer? It looks like one from the videos I saw. If the bit gets bound up (which it shouldn't) the bit gets held loosely in the machine. You stop the machine, unlatch the drill bit, pull the machine off, smack the bit with a mallet, and that's usually more than enough to get it loose.

That's what I did with the jackhammer I used and it was the same thing.
 
I'd imagine anything like that would have a dead-man switch on it, that one released, kills power to the motor or transmission.


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I would think the opposite approach might be better. One person manning it so that if it grabs, it will pop out of your hand and stop the drill. Hold it with enough pressure to drill, but not braced in a way where you'll get hurt if it binds.
 
Go to local bar. Recruit 2 or more workers. Instruct said workers on job requirements. Leave location. Return and pay only after the required holes have been created.
 
The one I used was manufactured by Wacker. The bit was held into the chuck of the machine loosely by a big spring, and didn't turn as such like a regular drill, but turned very slowly a few degrees at a time by impact from a hammer action inside the unit. I never experienced any sort of binding.

How deep are holes you want to make? Maybe you could get away with a heavy electric hammer drill and generator, if you have one? I rented an electric one to run some 1" water line through a poured concrete basement wall... cut through it like a hot knife through butter. A pnuematic might be overkill.
 
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Get you some chocolate and hire this guy! Maybe he could eat his way through?
54770192900521358178.png
 
Is it hilly or on a slope? For 50 holes, a crawler mounted drill from a quarry may be the ticket. Mark out hour holes and an hour later you have 50 holes and some piles of dust.
 
Get me some Bangalore torpedoes and a case of beer and I'll take care of it for free.

'Cause explosives...
 
You could use the John Henry approach and use a hand rock drill. Our Wilderness crews had to do that. Often took more than a day in granite.
 
Let'sgoflying! said:
There is no one around to hire this out.
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Really? Where in West Texas? The current drilling capital of the world? Drilling into volcanic or caliche rock can be tricky. Call a local water well driller. They can advise.
 
texashikergal02 said:
Really? Where in West Texas? The current drilling capital of the world? Drilling into volcanic or caliche rock can be tricky. Call a local water well driller. They can advise.
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Call a waterwell driller about fence post holes? Prolly not...
 
They will guide you to the resources you need, just saying.
 
Blasters drill a lot. Some excavators drill or know someone that does (because they blast).
 
upload_2017-4-1_16-56-2.jpegA little heavy but for small holes no sweat. Use a 4 foot steel and a cross bit. A small track drill would be easier and quicker.
 
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Zeldman said:
You don't have wetbacks.... I mean illegal aliens.... I mean undocumented workers in your area..?? :lol::lol::lol:
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Easy with the slurs there champ.

Also, my family members matching the other two descriptions are here in LA... not much used to anyone in Texas... though I'm sure they've crossed there too!
 
Is this surface rock? Why not buy flanged posts, drill smaller holes for anchors with a hammer drill and bolt them down.
 
Best way i know of to make holes in the ground. Eff shovels or post hole diggers (PHD's). I can set these off for you as well. You have to find them though. :D

I have made holes with these. So much fun... get few extra and we could put telephone poles in there.


Inert_M3_40_LB_DEMO_Shaped_Charge.jpg
 
Pneumatic drills are pretty hard to bind. The drill head is larger than the shaft, and the hammering action oversizes the hole as you drill. You could rent an electric rotary hammer, but 1 1/4 is the upper size range even for the big heavy duty roto hammers. I think your choice of a pneumatic hammer drill is the best choice. It'll drill reasonably fast and you would be out there all day with an electric roto hammer.

And as I said, don't worry about it binding. Just keep it straight in the hole as you proceed. You'll be surprised at how quickly it will drill.
 
Chip Sylverne said:
Is this surface rock? Why not buy flanged posts, drill smaller holes for anchors with a hammer drill and bolt them down.
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Volcanic rock isn't a flat surface,so getting the post plumb vertically would be difficult. The lava isn't suited for expansion anchors either. It would spall easily when the anchor is tightened.
 
3393RP said:
And as I said, don't worry about it binding.
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not understanding the recent local stories of busted arms and hands, then.
Need safety tips (besides personal protective equipment) - how to handle it.
 
Let'sgoflying! said:
not understanding the recent local stories of busted arms and hands, then.
Need safety tips (besides personal protective equipment) - how to handle it.
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Can't address directly since I haven't used one. Can say operators typically don't adhere to operating instructions or parameters. Do pay attention to the air supply and keep it within pressure and volume specs. Do keep an eye on the drill rod condition. And finally let the drill do the work.
 
3393RP said:
Volcanic rock isn't a flat surface,so getting the post plumb vertically would be difficult. The lava isn't suited for expansion anchors either. It would spall easily when the anchor is tightened.
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Around my neck of the woods, volcanic or igneous means primarily granite. I admit to being woefully ignorant of W. Texas geology.
 
Then there's the true pilot method. Rent a skidsteer with the proper hydraulic attachment, and do the job sitting down with a cool beverage in one hand...
 
Alternatively, you could get a water tank and pump and wash away the dirt. Once clean, affix some screen by shooting into the rock with cap fired nail gun. Then make boxes and pour concrete to get a level surface to affix the posts.
Pipes in rock will rust out pretty quick since there is no place for the water to drain. Lifting them up will preserve them.
 
cgrab said:
Alternatively, you could get a water tank and pump and wash away the dirt. Once clean, affix some screen by shooting into the rock with cap fired nail gun. Then make boxes and pour concrete to get a level surface to affix the posts.
Pipes in rock will rust out pretty quick since there is no place for the water to drain. Lifting them up will preserve them.
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Rust in the desert? Prolly not much. And he spec'd t posts which are coated. They will last many years.
 
Am told the standard is to seat the t-post into the rock with a handful of cement, not perfect but should keep out some moisture. We do get rain and rust here in w Tx. A plain steel part left out in....a carport will soon have a sheen of the red stuff.
The rock here is igneous/volcanic according to the geo's I've talked to. Much but not all is very light and porous. I am hopeful. That I don't bust my more important limbs.
 
Chip Sylverne said:
Around my neck of the woods, volcanic or igneous means primarily granite.
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Volcanic or igneous is just that, volcanic. Granite is metamorphic rock. Totally different. The bottom levels of the Grand Canyon are metamorphic, like bedrock of the planet. Hawaii is volcanic.

Dave, you are correct, a good portion of the SW Texas landscape is pretty volcanic near the surface, and a good bit of iron in the soil which will rust if not protected. The problem is that it's not all that hard, in a way, but it breaks in odd ways, and leaches water also. It just can be hard to get a good hole drilled into, but, once cemented, should hold, I would think.
 
texashikergal02 said:
Volcanic or igneous is just that, volcanic. Granite is metamorphic rock. Totally different. The bottom levels of the Grand Canyon are metamorphic, like bedrock of the planet. Hawaii is volcanic.

Dave, you are correct, a good portion of the SW Texas landscape is pretty volcanic near the surface, and a good bit of iron in the soil which will rust if not protected. The problem is that it's not all that hard, in a way, but it breaks in odd ways, and leaches water also. It just can be hard to get a good hole drilled into, but, once cemented, should hold, I would think.
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I beg to differ, and so does my Geo prof., as well as Wikipedia. Granite is not metamorphic.
https://en.m.wikipedia.org/wiki/Volcanic_rock
https://en.m.wikipedia.org/wiki/Granite

Quartzite, marble, slate are metamorphic.
 
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According to wiki, granite is an igneous rock. But I'll say this, you can't tell how rock will hold without seeing it and trying it. Rocks are all different.

"Debate has long centered on whether granite is igneous or metamorphic in origin. Originally granite was thought to form mainly from magmatic differentiation of basaltic magma, but geologists now believe there is simply too much of it for it to have formed this way, except locally."

So a lot of us did learn it was metamorphic.
 
2" Sds max rotohammer from Bosch. Some construction rental outfits have them.


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Jeez... Rock comes out of a volcano, it's igneus, those rocks and stuff merge with other stuff, they become sedimentary, they get buried for millions years and baked to a pulp, they become metamporphic,meaning they get baked into something new.. This isn't radical stuff. That being said, I'ts also not about flying, so lets go back there.....
 
texashikergal02 said:
Jeez... Rock comes out of a volcano, it's igneus, those rocks and stuff merge with other stuff, they become sedimentary, they get buried for millions years and baked to a pulp, they become metamporphic,meaning they get baked into something new.. This isn't radical stuff. That being said, I'ts also not about flying, so lets go back there.....
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You've got the schist of it...
 
Did it yesterday.
-it is laborious to lift that tool up a hill. Plus the hose (we had 500') and water, post pounder, drinking water etc. Very heavy, wears a person out quickly.
-the drilling is easy, you barely have to hold it while it beats the crap out of the rock.
-it will bind, but only when small hard pebbles fall into the hole - this was not a problem
-the largest bit available was 3" unlike posted above.
-did 50 holes in 3.5hrs.
-instead of concrete in the holes, I pushed the powdered rock and pebbles into the hole around the T posts, you cannot pull the T posts out now.

Two videos; one is slo-mo.


 
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