Blasting and Rock Breaking

[pczim]

This is what I use....

 

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[tamrock]

So now we build our own. Hydraulics and pneumatics really are not that hard to understand. Just have to be smart about discharging all pressure before maintenance activitles.

Indeed. Its is the sudden release of stored energy that is the cause of many injuries and fatalities that was described in one of my msha annual refresher classes. So much of what your dealing with in not just the mining industry is like a mousetrap loaded and set to snap. I wished a lot of drivers on the road would understand things that way when I see them driving down the road at 60 mph and staring at their phones, not realizing their own body is then subject to any sudden change in its velocity known as inertia force.

 

[gold tramp]

Indeed. Its is the sudden release of stored energy that is the cause of many injuries and fatalities that was described in one of my msha annual refresher classes. So much of what your dealing with in not just the mining industry is like a mousetrap loaded and set to snap. I wished a lot of drivers on the road would understand things that way when I see them driving down the road at 60 mph and staring at their phones, not realizing their own body is then subject to any sudden change in its velocity known as inertia force.

Last season,
I learned first hand nursing my son back to health from a high speed head on to his side of the car.
They had a car on the tow acted like an anchor.
Amazing what a body can come back from.
Gt.....

BlasterJ,
Did you know mitchel, from your pics looks like your over by Snyder's place?

 

[BlasterJ]

Last season,

BlasterJ,
Did you know mitchel, from your pics looks like your over by Snyder's place?

I don't know them, my place is in the high desert in San Bernardino County.

 

[BlasterJ]

View attachment 1821164

This is what I use....

That's South African, right? I believe Autostem 1.4 products are also made there?

What sort of licenses/insurance do you need in your country to transport high explosives and blast?

Cheers,

John

 

[monsterrack]

I've mined a lot of stone for flint knapping so we never wanted to blow it up. We would use air hammer drills with a 2ft bit then a 4ft bit. Drill our holes about 3ft back from the face and spread them 4ft apart. We just used black powder and cannon fuse. It would break the face off and not damage our stone with blast cracks. No license needed just some common knowledge.

 

[pczim]

That's South African, right? I believe Autostem 1.4 products are also made there?

What sort of licenses/insurance do you need in your country to transport high explosives and blast?

Cheers,

John

Yes made in South Africa. My mines are in Zimbabwe. I have a licensed blaster who works for me. Alongside that you need proof that you have a secure magazine to be issued a license to purchase.

 

[OwenT]

Hi John, I'm going to ask a different question here. Maybe there's someone else too that has useful experience. I know the sierra blaster and micro blasters have been talked about a lot here on T-net already but I haven't been able to find great answers to my question yet.

I am interested in a micro-blaster or sierra blaster for mineral collecting and possibly gold prospecting purposes. It's one of those things I don't exactly have a spot for right now where I NEED one, but I tell myself I will use if I had one and seeing a good deal on a used sierra blaster I'm wondering if I should jump on it. I'm looking for the lightest, most portable system. First, I thought the original microblaster with one head and a pull lanyard trigger would be best because no compressed air or electricity source is needed for a trigger. Then I realized that with only one head you don't have any control over how rock will break. I also read that the microblaster charges can be pretty finicky while sierra blasters are more robust. How compact of a system can ou expect running a sierra blaster of a battery? How big of a battery is needed and can all sierra blaster systems be used with a battery? Also, is one of these really practical for trying to get crystals out of wall rock or would they be too destructive? I read the sierra blaster charges pack more of a punch.

Then there's the drill and weight associated with that. Not sure how many holes you can drill on a charge.

Just looking for some advice, thanks!

 

[tamrock]

I do know some crystal miners and they crack rock with hydraulic rock splitters and tungsten carbide chain saws to carefully remove the specimens, so not to damage them. As for a drill, Hilti makes an electric jackleg. It's not near as powerful as a pneumatic, but for a tedious application and a whole lot less hassle in operation it might be what your looking for. As for a blasting and breaking rock, seems there's quite a few options anymore to look into. https://m.facebook.com/story.php?st...id":573453863102514,"role":1,"share_id":0}]}}

 

[gold tramp]

I do know some crystal miners and they crack rock with hydraulic rock splitters and tungsten carbide chain saws to carefully remove the specimens, so not to damage them. As for a drill, Hilti makes an electric jackleg. It's not near as powerful as a pneumatic, but for a tedious application and a whole lot less hassle in operation it might be what your looking for. As for a blasting and breaking rock, seems there's quite a few options anymore to look into. https://m.facebook.com/story.php?st...id":573453863102514,"role":1,"share_id":0}]}}

Pricey Set up Hilti....

 

[BlasterJ]

Hi John, I'm going to ask a different question here. Maybe there's someone else too that has useful experience. I know the sierra blaster and micro blasters have been talked about a lot here on T-net already but I haven't been able to find great answers to my question yet.

I am interested in a micro-blaster or sierra blaster for mineral collecting and possibly gold prospecting purposes. It's one of those things I don't exactly have a spot for right now where I NEED one, but I tell myself I will use if I had one and seeing a good deal on a used sierra blaster I'm wondering if I should jump on it. I'm looking for the lightest, most portable system. First, I thought the original microblaster with one head and a pull lanyard trigger would be best because no compressed air or electricity source is needed for a trigger. Then I realized that with only one head you don't have any control over how rock will break. I also read that the microblaster charges can be pretty finicky while sierra blasters are more robust. How compact of a system can ou expect running a sierra blaster of a battery? How big of a battery is needed and can all sierra blaster systems be used with a battery? Also, is one of these really practical for trying to get crystals out of wall rock or would they be too destructive? I read the sierra blaster charges pack more of a punch.

Then there's the drill and weight associated with that. Not sure how many holes you can drill on a charge.

Just looking for some advice, thanks!

If I were buying a system new, I would go with the Sierra Blaster. The charges are a bit larger (10mm diameter vs 3/8) and waterproof. Both can be used with multiple heads and weigh similarly. They hold 1-2 grams of material, and you can add booster cartridges with either if you are able to drill a deep hole.

Both companies have a similar pricing model - their equipment is expensive, but the charges are reasonably-priced. Considering that a blasting cap is $7+ and a small pyrotechnic rock breaker from Autostem or Royex is around $10, paying $1-2/ea for the Sierra Blaster or EZ-Break charges isn't too bad.

The compressed air for the "shock tube" initiation on the EZ-Break isn't a big deal if you can rig up a regulator to use bulk CO2 paintball tanks. You can also use a CO2 bike tire inflater.

On the Sierra Blaster, you have an electric match that needs around 1amp to fire. This is the same system that pro fireworks enthusiasts use to shoot their cakes and mortars, and those are often fired from a LiPo drone battery that weighs around 1/2lb. You can also use a "blast box" like you use for real blasting. Unfortunately, they may not sell you one without a blaster's license.

Either of these will break several cubic feet of rock with one head if you are shooting a boulder or something with 2 exposed rock faces. Expect to do more drilling and more shooting if you are trying to dig something out of a solid wall of rock in a mine/etc. It still works, but it's less dramatic.

Get a high quality cordless drill in any case. The Ryobi 18V isn't beefy enough. Go with at least the DeWalt or Milwaukee in a model that is rated to drill 1" holes and takes SDS+ bits. The 36V models are even better, but more expensive, and of course the batteries cost more. Get a set of drill bits in the right diameter, from 4 inches long, to 6, 8, 12, 16 and 24". Do not try to drill the holes in one pass - start with a short drill and keep changing bits as you go. Those little drill bits get hot FAST and you really want to rotate through them so that they don't burn up. They also wander a lot if if you drill with one big drill.

If you are shooting in-place rock, I recommend making a "burn cut" or drilling a cloverleaf pattern of bigger holes in the middle of the rock you are trying to break. Start small and then ream them out to 3/4" or even 1" if possible. The rock needs somewhere to expand into when you are breaking into a hard mass of stone.

Get extra batteries, so that you can swap them out as well as let them cool down between holes. Batteries overheat just like drill and bits do.

Also, start a "blast log" and document your work. You my want to apply for a blaster's license in your state later, and you can use this as "experience" in places like California that require "3 years of documented blasting experience" in order to apply.

 

[OwenT]

Thanks for the great info

 

[BlasterJ]

Here is the picture of the CO2 system for setting off EZ-Break heads. When you have multiple heads go off at once, you can make the crack propagate where you want it. You can also drill empty holes between the heads to encourage it to crack in a certain way.

 

[tamrock]

Pricey Set up Hilti....

Yeah they are, but considering the air source required, plus all the pipe and hose needed for a pneumatic unit these Hilti drills might be an option. I talked to these Hilti dudes at a trade show and they developed the drill for the deep mines of South Africa, as the atmospheric pressure down so deep can inhibit the pneumatic drills performance. The pneumatic machines need so much more air pressure at the depth in order for the exhaust to expel against such pressures below, plus all that expanding air exhaust with all its condensation added to the heat in those deep mines can be a living hell for an African miner. There's also some hydraulic jacklegs and sinker drills out there made by Atlas Copco and Stanley. One of the things they can do with hydraulic is operate under water, but I think those complete with a power pack, either internal combustion or electric might cost around $12k or maybe more?. I guess breaking tons of rock has and will always be an expensive endeavor.

 

[BlasterJ]

Yeah they are, but considering the air source required, plus all the pipe and hose needed for a pneumatic unit these Hilti drills might be an option. I talked to these Hilti dudes at a trade show and they developed the drill for the deep mines of South Africa, as the atmospheric pressure down so deep can inhibit the pneumatic drills performance. The pneumatic machines need so much more air pressure at the depth in order for the exhaust to expel against such pressures below, plus all that expanding air exhaust with all its condensation added to the heat in those deep mines can be a living hell for an African miner. There's also some hydraulic jacklegs and sinker drills out there made by Atlas Copco and Stanley. One of the things they can do with hydraulic is operate under water, but I think those complete with a power pack, either internal combustion or electric might cost around $12k or maybe more?. I guess breaking tons of rock has and will always be an expensive endeavor.

That's an interesting setup. It looks like they take special drills and steels? One of my observations with pneumatic rock drills is that the big, flat-faced drills last about 10X as long as the small spiral-fluted drills used on electric hammer drills. I'm guessing the TE-MD20 is made for heavy industrial use and probably has good tooling.

Maybe when these have been out long enough for used/refurb units to hit the market...

 

[tamrock]

That Hilti more than likely runs the same 7/8"x 4-1/4" hex shank drill rod like most all the pneumatic mining and construction rock drills use. I got some rods in my garage that a dealer gave me to find a place to try out. It's a brand made in south Korea. The use a tapered knock off socket carbide bit. The sizes of bit used on these type rods range from 1-1/8" to 1-7/8" in diameter and come in a blade cross carbide or button carbide design. I've never looked online for any used Hilti jacklegs before, but wouldn't be surprised you might just find one. I'm thinking its been on the market a good 10 years now. Mines here that have tested them have told me its pretty gutless compared to the big 90 pound pneumatic drills, but it really wasn't designed to be a high production machine. It has its place imo and I wouldn't mind owning one.

 

[BlasterJ]

The Pionjars and Cobra Combi's take 7/8 x 4 1/4 tooling. I found a nice 40lb Chicago Pneumatic sinker drill near me for a good price, but it was unfortunately set up for 3 1/4" steels.

If you wanted a portable drill, there are a boatload of used Cobra Combi's on eBay right now. Have a parts guy who can get you going too.

 

[Mad Machinist]

I do know some crystal miners and they crack rock with hydraulic rock splitters and tungsten carbide chain saws to carefully remove the specimens, so not to damage them. As for a drill, Hilti makes an electric jackleg. It's not near as powerful as a pneumatic, but for a tedious application and a whole lot less hassle in operation it might be what your looking for. As for a blasting and breaking rock, seems there's quite a few options anymore to look into. https://m.facebook.com/story.php?st...id":573453863102514,"role":1,"share_id":0}]}}

As far as I know Hilti discontinued this. Not sure why but I'm gonna bet reliability was an issue.

 

[tamrock]

The Pionjars and Cobra Combi's take 7/8 x 4 1/4 tooling. I found a nice 40lb Chicago Pneumatic sinker drill near me for a good price, but it was unfortunately set up for 3 1/4" steels.

If you wanted a portable drill, there are a boatload of used Cobra Combi's on eBay right now. Have a parts guy who can get you going too.

Well if you have some 4-1/4" shank rod, just use an abrasive wheel chop saw and cut slow, not to overheat exactly one inch off the striking end and champher the perimeter a bit on the belt sander and you'll have a 7/8 - 3-1/4 inch steel to run in the CP. It's done all the time and you don't need to stock but one length of shank.

 

[tamrock]

As far as I know Hilti discontinued this. Not sure why but I'm gonna bet reliability was an issue.

Yeah I don't know. Nobody in the US would buy them that I knew of. Hilti was really hitting the road a few years back calling on some of the mines to give it a try, but I don't think they found any takers. I do think an electric drill like they made would come in handy for a one to two man little operation. Especially for someone who needs to mine discreetly and kinda like under the radar with not a lot of exposed surface equipment such as noisy air compressors for all the nosy kind of folks to see and hear.