Rock Drill Care and Feeding

BlasterJ

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I picked up a pair of Chicago Pneumatic drills that I'm in the process of rebuilding. I'll probably do a Mining Journal article on this at some point.

Does anyone have any pneumatic tool tips that they would like to share? I'd never taken one of these units apart before, and I was surprised at how much simpler they are inside vs. the gas powered tools I usually work on.
 

russau

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My son also got ahold of several C.P. Pneumatics drills and chisels that were in a bucket for many years and full of rust. I saw pictures of C.P. drills just like these but from WW2 manufacturing plants. I was sure that they were dead on arrival BUT to my surprise I cleaned off the outside of them and shook the chisels and they were free... so I got out my WD40 and give them a squirt or 2 and let them set over night and the next day I fired up my compressor and low and behold they worked just fine after all this time, HAPPY ME !!
 
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BlasterJ

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My son also got ahold of several C.P. Pneumatics drills and chisels that were in a bucket for many years and full of rust. I saw pictures of C.P. drills just like these but from WW2 manufacturing plants. I was sure that they were dead on arrival BUT to my surprise I cleaned off the outside of them and shook the chisels and they were free... so I got out my WD40 and give them a squirt or 2 and let them set over night and the next day I fired up my compressor and low and behold they worked just fine after all this time, HAPPY ME !!

That's awesome! I picked up two CP14 (15lb class) drills this week for cheap because they were seized up. It took about 30 minutes to fully field-strip them. Then all the parts went into my ultrasonic cleaner with some hot Simple Green. With a little wire-wheel polishing, a couple of seals and some new paint, they're good to go. I'm amazed at how simple these are to service - much less difficult than working on a small engine.

I've come to realize that the spray paint job is sort of like an "hour meter" for air tools. You get an idea of how much use it's had since the last service by the amount of paint left.
 
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BlasterJ

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The one's my son found were void of any paint. BUT now they operate like new and are the most powerful P. chisel I've ever used !

If you feel like a project, you can probably get them apart easily and give the corroded areas a little wire wheel or emery cloth reconditioning and maybe lap the valves if they are rusty.
 

russau

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I had thought of that idea about taking them apart BUT then again why mess with it when it runs just great as- is ! Now if my son was in the mode to sell them , then yes that would be the way to go ! He "gave" me 3 tools to try out and see what shape they were in and they were able to get up - n - running with a minimum amount of fiddling . I told him to clean them up and put them on "marketplace " on the net. He said he would sometime.
 
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BlasterJ

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The thing I am discovering about big air tools: Unlike gas equipment, they have very few soft seals of any kind or piston rings. Usually, they just have a couple of generic o-rings and maybe a valve poppet for the trigger. Doing a clean, lubricate and reassemble is often enough to get them running good again. Rusty or worn stuff can be cleaned up or machined.

The downside compared to small engines is that all of the "hard parts" are very expensive. Like $100-400 for a valve, piston, etc. So it's worth taking something out for plating or resurfacing if it can be salvaged. Or just waiting to find a "parts unit" instead of actually buying the part.
 

russau

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My desire now is to start making different bits for this C.P. hammer . I have a chisel and made a bit to drive ground rods into the earth for my 10 K.W. generator. SORRY FOR GOING OFF TOPIC !
 
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BlasterJ

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My desire now is to start making different bits for this C.P. hammer . I have a chisel and made a bit to drive ground rods into the earth for my 10 K.W. generator. SORRY FOR GOING OFF TOPIC !

I made one of those too! The only tricky thing is that welds eventually break from the hammering. It works best if you can make the thing either 1-piece or have the tip slip/screw on mechanically and not depend on the welds so much.
 

russau

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I have a TIG & a MIG welder and have done this for many a moons ! If it breaks I'll just weld it back together again !:occasion14: I plan to make a air throttle for one of these and use it for different thing's wood/stone/ metal and my son's hard head !:laughing7:
 

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I've gone through a few pneumatic rockdrills mostly the Gardner Denver S83 and yes all are pretty simple to do and just about all of them no matter the brand work on the same concept. The real skill on a handheld rockdrill would be knowing the in's and out on those Ponjar machines. When I worked for Brunner & Lay, I had a customer who started a business back in the 80s solely selling and servicing the Copco Ponjar. He would buy around $35k to $40k a year in all the moil points, clay spades and a lot of H-Thread rock bits and steel also to resell. He got cancer and him and I even beat around the bush on acquiring his business Pioneer Sales & Service. He told me the important part of the business was to be an expert in the service and repair of the Ponjar which didn't sound all that simple to me. His key customer was the US Forest Service by as much as 80% of his business was dealing with all the Ponjar's in all the west of the USFS and BLM fleet. His name was Mel Dirksen a Mennonite he was and just one of the friendliest kind of folk you would ever meet. Sadly the cancer got the best of him, but he worked on to just about the very end. I'm just grateful my job allowed me to come by such fine folks like Mel. It was people like him that would make some of the stinkers I have to deal with all the better.
https://www.google.com/amp/s/www.le.../obituary.aspx?n=melvin-dirksen&pid=160934705
 

russau

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YES there are lot's of real nice people out there if you'll just listen to what they have to say ! I also have meet lot's of real nice people in my travels ! THAT was my treasure in life to know them face to face and the memories that came from it !:occasion14:
 
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BlasterJ

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I've gone through a few pneumatic rockdrills mostly the Gardner Denver S83 and yes all are pretty simple to do and just about all of them no matter the brand work on the same concept. The real skill on a handheld rockdrill would be knowing the in's and out on those Ponjar machines. When I worked for Brunner & Lay, I had a customer who started a business back in the 80s solely selling and servicing the Copco Ponjar. He would buy around $35k to $40k a year in all the moil points, clay spades and a lot of H-Thread rock bits and steel also to resell. He got cancer and him and I even beat around the bush on acquiring his business Pioneer Sales & Service. He told me the important part of the business was to be an expert in the service and repair of the Ponjar which didn't sound all that simple to me. His key customer was the US Forest Service by as much as 80% of his business was dealing with all the Ponjar's in all the west of the USFS and BLM fleet. His name was Mel Dirksen a Mennonite he was and just one of the friendliest kind of folk you would ever meet. Sadly the cancer got the best of him, but he worked on to just about the very end. I'm just grateful my job allowed me to come by such fine folks like Mel. It was people like him that would make some of the stinkers I have to deal with all the better.
https://www.google.com/amp/s/www.le.../obituary.aspx?n=melvin-dirksen&pid=160934705

I have rebuilt 3 Pionjars and a Cobra Combi. A "minor" service is around 4 hours of labor and a full rebuild/paint is 8+ hours. The parts from Atlas-Copco are ungodly expensive. But things like chuck inserts, pistons, rings and bearings are the same as the China knock-off and available affordably. Cylinders can be sent out for honing and replating for about $350.

There is a fellow in Maine who imports batches of parts and will do service and overhauls. That's the only "for hire" service that I know of since your guy passed away and May's Trail Equipment in Idaho is gone. If you have customers asking for this, we could all probably make something happen.
 

tamrock

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I have rebuilt 3 Pionjars and a Cobra Combi. A "minor" service is around 4 hours of labor and a full rebuild/paint is 8+ hours. The parts from Atlas-Copco are ungodly expensive. But things like chuck inserts, pistons, rings and bearings are the same as the China knock-off and available affordably. Cylinders can be sent out for honing and replating for about $350.

There is a fellow in Maine who imports batches of parts and will do service and overhauls. That's the only "for hire" service that I know of since your guy passed away and May's Trail Equipment in Idaho is gone. If you have customers asking for this, we could all probably make something happen.
Thats what I'm thinking. I know Mel did quite well being coupled to business with the USFS. I can get all the consumables like the drill steel, bits and chipping accessories for a flat discount from B&L because we're one of their largest dealers in the states. Dang those are a lot more complex than a pneumatic machine if it takes those kind of hours to go through them. I think I'll see what I can find out about who you gotta get with on supporting the Cobras and Ponjars used by the USFS. That's something I tried before in the past and it's definitely heading down a rabbit hole when you wanna land any business at an agency such as them. Real easy to give up on, when you know there's much easier pickings to chase after. Might be a good little sector for us as we've got stocking warehouses in Alaska, Utah Colorado, Idaho, Nevada, Montana and I recently encouraged a former comrade to jump ship at the old job to head up business in Arizona. Mel delt with the intire USFS throughout the west from Denver.
 
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BlasterJ

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If your bench is set up right, you could probably do the service in less time. The biggest time sink is breaking them down and cleaning all of the mud, baked on grease and trash out of the cylinder fins and top-end parts under the covers. And paint and drying time if you want to do that.

The two reasons they stop working are either overheating from all of the junk on them (they run, quit and then won't start for 30 minutes) or low compression from rings/etc. They will either not start or have no power with worn out rings.

Usually, you also want to open up the crank case and do the bearings if it's the first time you're rebuilding one with a lot of use. That involves pressing out/in bearings and such.

The "bottom end" service is like a pneumatic drill, plus the steps needed to fit rings and recondition/deglaze the cylinder. The cylinder and bottom end (drill parts) are identical between the Pionajr 120 and Cobra Combi. And also the China clone, hence the affordable ring kits and such.

I would call a "basic" service cleaning, piston rings, gaskets, fuel filter and a chuck insert.

The two "not working" types I have seen are "worn to hell by a Conservation Corp camp" or "Put away wet and seized/corroded." A lot are the second. If you get them apart, they often have little wear on the cylinder and hard parts and rings/bearings/gaskets bring them back to life. If they are too far gone, the Aluminum castings get it and you scrap them for parts.
 
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BlasterJ

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Thanks to everyone who helped with this discussion! My article on rock drills made it into this month's ICMJ. Also @Tamrock, my friend in Maine has an ad in there for his Pionjar and Cobra Combi rebuilds. I think he ships nationally and does a 6 month warranty.
 

augoldminer

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i used Gardner Denver S83 and 63s jack legs for many years underground.

the best thing to use with a rock drill is a good inline lubricator and good rock drill oil.
https://slideplayer.com/slide/2495332/.

i had one Gardner Denver S83 that stayed 400 feet up in a stope for 4 years and was never brought down for repairs.

All my drills, tuggers, slushers, pneumatic motors and other pneumatic tools had oilers on them and i had few problems ever with pneumatic tools.

Don't use what they call rock drill grease it does not flush drill mud out of the drill fast enough and makes a mess of sand and grease.
 

HardRockNM

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i used Gardner Denver S83 and 63s jack legs for many years underground.

the best thing to use with a rock drill is a good inline lubricator and good rock drill oil.
https://slideplayer.com/slide/2495332/.

i had one Gardner Denver S83 that stayed 400 feet up in a stope for 4 years and was never brought down for repairs.

All my drills, tuggers, slushers, pneumatic motors and other pneumatic tools had oilers on them and i had few problems ever with pneumatic tools.

Don't use what they call rock drill grease it does not flush drill mud out of the drill fast enough and makes a mess of sand and grease.

I know of an S83 that was underwater in a shrinkage stope for 4-5 years. When the mine was pumped back out, the drill doctor had it back in service within the day.
 

gold tramp

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i used Gardner Denver S83 and 63s jack legs for many years underground.

the best thing to use with a rock drill is a good inline lubricator and good rock drill oil.
https://slideplayer.com/slide/2495332/.

i had one Gardner Denver S83 that stayed 400 feet up in a stope for 4 years and was never brought down for repairs.

All my drills, tuggers, slushers, pneumatic motors and other pneumatic tools had oilers on them and i had few problems ever with pneumatic tools.

Don't use what they call rock drill grease it does not flush drill mud out of the drill fast enough and makes a mess of sand and grease.

We called the inline oiler the pig.
Gt...
 
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BlasterJ

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I know of an S83 that was underwater in a shrinkage stope for 4-5 years. When the mine was pumped back out, the drill doctor had it back in service within the day.

I could imagine that. I bought two CP14 small drills that were seized up and neither the chucks nor triggers moved. After hammering them apart with a chunk of hardwood, the rest was easy.

I like to put all of the parts in a bath of hot Simple Green for a couple of hours to get rid of the paint, grease, etc. and then see what is needed One needed the valve box cleaned up with some emery cloth and lapping compound and they both needed new valve seats and a coat of paint. Not much to go wrong there!
 

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