Blasting and Rock Breaking

JosephT

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Jan 28, 2019
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That can actually get down right deadly using that much explosives. Fly rock can travel a long damn way if the charges are too large.
Tell me about it I had to run from some fly rock and not knowing where it was going I kept my eye on it so I could dodge it and the air blast was deafening.

Have you ever had the headache from nitro based dynamite? That is by far the worst headache I have ever had and could not see for several hours either. My doctor said it caused by to much blood in my brain do to the dilated blood vessels after the nitro was absorbed through my finger tips. From that point on I wear gloves when loading holes.
 

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BlasterJ

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Apr 2, 2020
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Tell me about it I had to run from some fly rock and not knowing where it was going I kept my eye on it so I could dodge it and the air blast was deafening.

Have you ever had the headache from nitro based dynamite? That is by far the worst headache I have ever had and could not see for several hours either. My doctor said it caused by to much blood in my brain do to the dilated blood vessels after the nitro was absorbed through my finger tips. From that point on I wear gloves when loading holes.

I can't speak for our other blaster here, but I personally try not to get nitroglycerine dynamite. Emulsion sticks do basically the same thing, don't cause headaches and don't get dangerous if stored too long.

Here's one they stock locally here:
Senatel? Ultrex?
 

Mad Machinist

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Aug 18, 2010
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Tell me about it I had to run from some fly rock and not knowing where it was going I kept my eye on it so I could dodge it and the air blast was deafening.

Have you ever had the headache from nitro based dynamite? That is by far the worst headache I have ever had and could not see for several hours either. My doctor said it caused by to much blood in my brain do to the dilated blood vessels after the nitro was absorbed through my finger tips. From that point on I wear gloves when loading holes.

I stay away from nitro as much as possible. Over the years I have found very, very few situations where it needed used. I am really interested in gaining more experience with the 1.4s though. If it will work like I think it will with more experience, then I don't see the need for any small guy to use high x again.
 

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BlasterJ

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Apr 2, 2020
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I stay away from nitro as much as possible. Over the years I have found very, very few situations where it needed used. I am really interested in gaining more experience with the 1.4s though. If it will work like I think it will with more experience, then I don't see the need for any small guy to use high x again.

I just got done blasting a new entrance for a cave property for the land trust I do work for. I broke up and moved about 3.5 cubic yards of limestone using 40gm and 5 gram 1.4s. It worked great on solid rock, leaving larger pieces and very little air blast. You might need to at least keep some caps and Kinesticks around for weaker rock - once it's fragmented, you can't easily reshoot with these. You can still get away with the Job Box magazine for the caps if you go with "non mass detonating" packaged detonators (which seem to be all of the electric or NONEL with 12' or longer leads).
 

JosephT

Jr. Member
Jan 28, 2019
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36
NC
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I stay away from nitro as much as possible. Over the years I have found very, very few situations where it needed used. I am really interested in gaining more experience with the 1.4s though. If it will work like I think it will with more experience, then I don't see the need for any small guy to use high x again.

I Don't think most people use it anymore my experience with it stated in the early 90s and I see less and less of it. I read some where that only one place in the US still makes it. One thing about it that I don't see with other types is the ability to cut up the sticks for a smaller charge if you don't need the whole stick. Of course if I hadn't been cutting the sticks in half I probably wouldn't have gotten it on my skin and got the headache from hell.
 

gold tramp

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Dec 30, 2012
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Tell me about it I had to run from some fly rock and not knowing where it was going I kept my eye on it so I could dodge it and the air blast was deafening.

Have you ever had the headache from nitro based dynamite? That is by far the worst headache I have ever had and could not see for several hours either. My doctor said it caused by to much blood in my brain do to the dilated blood vessels after the nitro was absorbed through my finger tips. From that point on I wear gloves when loading holes.

Worse headache I ever had, nitro patch in hospital.

Gt....
 

Mad Machinist

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Aug 18, 2010
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Southeast Arizona
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I just got done blasting a new entrance for a cave property for the land trust I do work for. I broke up and moved about 3.5 cubic yards of limestone using 40gm and 5 gram 1.4s. It worked great on solid rock, leaving larger pieces and very little air blast. You might need to at least keep some caps and Kinesticks around for weaker rock - once it's fragmented, you can't easily reshoot with these. You can still get away with the Job Box magazine for the caps if you go with "non mass detonating" packaged detonators (which seem to be all of the electric or NONEL with 12' or longer leads).
I'd have to run it by the local ATF agent here but with the
smaller stuff that needs further breakage, the Sierra Blaster cartridges will fire off of a electronic ignition box. And I can also tell you that the Sierra Blaster cartridges will set off Tannerite, although tannerite used in this application requires a license. The license isn't hard to get, just more of a pain getting through a the paperwork and inspections.
 

Mad Machinist

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BlasterJ

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I Don't think most people use it anymore my experience with it stated in the early 90s and I see less and less of it. I read some where that only one place in the US still makes it. One thing about it that I don't see with other types is the ability to cut up the sticks for a smaller charge if you don't need the whole stick. Of course if I hadn't been cutting the sticks in half I probably wouldn't have gotten it on my skin and got the headache from hell.

As far as I know, demolitions companies still like using it because it can be bought in very high-velocity formulations that shatter reinforced concrete and can cut a limited amount of steel. C4 and linear shaped charges are really expensive, so dynamite is a good fit for all of the odd jobs in that industry.

Also, you can cut emulsion sticks up - the inside is like cookie dough. I use 1/3-1/2 stick to prime ANFO. I still wear gloves, but I don't think it's that much of a health hazard.
 

gold tramp

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Some pics would be nice if you guys don't mind, maybe hole drilling, rock cracking, wedge n feather work not so much the explosives talk.
More of the end result.
The videos don't work for me.
Thanks..
Gt ....
 

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BlasterJ

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Some pics would be nice if you guys don't mind, maybe hole drilling, rock cracking, wedge n feather work not so much the explosives talk.
More of the end result.
The videos don't work for me.
Thanks..
Gt ....

Here are the Autostem non-detonating cartridges we have been talking about.
autostem1.JPG

Here is a 1.1lb stick of packaged emulsion ready to get loaded:
IMG_20200224_150325.jpg
 

JosephT

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Jan 28, 2019
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As far as I know, demolitions companies still like using it because it can be bought in very high-velocity formulations that shatter reinforced concrete and can cut a limited amount of steel. C4 and linear shaped charges are really expensive, so dynamite is a good fit for all of the odd jobs in that industry.

Also, you can cut emulsion sticks up - the inside is like cookie dough. I use 1/3-1/2 stick to prime ANFO. I still wear gloves, but I don't think it's that much of a health hazard.

I haven't seen that type of emulsion stick the ones I have seen weren't that stiff it was more like jelly in a plastic tube.
 

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BlasterJ

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I haven't seen that type of emulsion stick the ones I have seen weren't that stiff it was more like jelly in a plastic tube.

I think the earlier packaged products were just a plastic tube filled with the same slurry/watergel type products that they pump out of the bulk truck. The newer ones have a thick emulsion that isn't made to be squirted down a hole. You can cut it or form it into a simple shaped charge if you need to break a boulder or something.
 

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BlasterJ

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I'd have to run it by the local ATF agent here but with the
smaller stuff that needs further breakage, the Sierra Blaster cartridges will fire off of a electronic ignition box. And I can also tell you that the Sierra Blaster cartridges will set off Tannerite, although tannerite used in this application requires a license. The license isn't hard to get, just more of a pain getting through a the paperwork and inspections.

If you are renewing or applying for a new ATF license, get the "Type 20: Manufacturer of High Explosives." It only costs a little more, and it allows you to do things like mix binary explosives you get in kit form (they do consider this manufacturing if it's for any commercial use) or custom-make your own rock breaking cartridges.

For blasting caps, you can build a second job box magazine and keep it 10' away from the first one, as long as the caps say "1.4B" and not "1.1B."

I'm going to be trying out the Sierra Blaster in a week or so. Looking forward to it!
 

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BlasterJ

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Update: I've been trying out a Sierra Blaster system on loan. So far, I'm very impressed with the quality of all of the parts and workmanship. Ignition has been 100%, both on a cheap 800W generator and a 400W inverter. I'll try my blasting machine on it next weekend.

sierra1.jpg
 

Mountaineer2020

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Update: I've been trying out a Sierra Blaster system on loan. So far, I'm very impressed with the quality of all of the parts and workmanship. Ignition has been 100%, both on a cheap 800W generator and a 400W inverter. I'll try my blasting machine on it next weekend.

View attachment 1835885

What did you end up drilling holes with? I have no experience hard rock blasting but have a Rigid 18v battery drill and a corded Rigid battery drill from doing remodel work and setting survey monuments. Have the ezebreak system in the box still. The corded version used too much juice for a 1800w generator. I'll probably use them initially but would like to upgrade eventually. Mine access is pack in.
 

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BlasterJ

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What did you end up drilling holes with? I have no experience hard rock blasting but have a Rigid 18v battery drill and a corded Rigid battery drill from doing remodel work and setting survey monuments. Have the ezebreak system in the box still. The corded version used too much juice for a 1800w generator. I'll probably use them initially but would like to upgrade eventually. Mine access is pack in.

Any SDS+ hammer drill will work. The EZ-Break uses 3/8" holes and the Sierra Blaster takes 10mm holes. Whatever you do, I actually recommend the SDS+ sized drill over a larger SDS-MAX equipped unit. The larger units have a lot more power, but they do fewer blows per minute, so the power is basically wasted on small holes like the micro blasters use.

The 18V tools will do the job just fine, especially if you have multiple battery packs. Your other alternative is to get a smaller SDS+ corded drill like a 1 1/8" rated Makita or similar.

The July issue of ICMJ's Mining Journal has my article on Micro Blaster if you want to read more. It's about 5 pages.
 

Mountaineer2020

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The July issue of ICMJ's Mining Journal has my article on Micro Blaster if you want to read more. It's about 5 pages.

Thank you, Read the article very helpful. In the article you talked about a wedge shaped blast. How do you set the drill pattern up for that and is the blaster hole drilled straight into the rock face or at an angle? Also I was wondering where the blast hole is drilled into a vertical surface will the blast achieve enough pressure without gravity pushing down on the detonator? I have the simple one head ezebreak and from what you wrote it relies on the weight of the blasting head to block the hole and build pressure. Hopefully getting out and blowing up a boulder this weekend.
 

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BlasterJ

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Thank you, Read the article very helpful. In the article you talked about a wedge shaped blast. How do you set the drill pattern up for that and is the blaster hole drilled straight into the rock face or at an angle? Also I was wondering where the blast hole is drilled into a vertical surface will the blast achieve enough pressure without gravity pushing down on the detonator? I have the simple one head ezebreak and from what you wrote it relies on the weight of the blasting head to block the hole and build pressure. Hopefully getting out and blowing up a boulder this weekend.

If you're trying to do a wedge shot, you drill the holes at around 45 degrees, so that the holes are getting closer together at the bottom. If you shoot 2-4 of them together, you can often eject a wedge-shaped piece of rock from a rock face with no exposed sides. You can also make a wedge-shaped pattern with a bunch of holes and use expanding grout to bust out a wedge.

When you just have one head, you might try a "burn cut," as in drilling some big (i.e. 1" or bigger) holes and setting your blast hole a few inches away, so that it blows out into the pre-drilled area. Once you have a free face started, it gets easier.

I might do an "advanced micro blasting" article later this year as it sounds like folks are interested. I really love my Pionjar gas drill for making big relief holes. But a regular SDS+ drill witll work too.

As for horizontal shots, the inertia of the blast head is enough to keep the pressure contained. It does work a bit better if you can put a sandbag or rock on top of a head placed into the rock vertically, but it still works.
 

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Reed Lukens

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On our Sierra Blaster 6 head system, even horizontal shots will blow the heads out of the drill hole, so we block them in with 2" or bigger branches cut to size. We were blasting about 40' in our tunnel last week after getting some great readings with a friends Goldmonster, but after taking the 5000 in last week and setting up for the blasts, my partner had forgotten our air pump... and down in that canyon, the air gets thin before you even go in... so we only got a few rounds in where I was set for a bunch. We're not getting any younger these days :)
 

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