DREDGING FOR GOLD

[Silicon John]

I have a question and I am sure that a lot of prospectors have experienced this. What is the best way to keep the dredge hose form clogging? My experience is limited to a two inch backpack dredge that I tried a few times one summer on creeks here in California. I even drilled a hole and put in a bolt across the input to hold back rocks larger than 1 inch. But now and then a flat, oblong shaped rock, would go in and turn sideways. I would have to stop and work it out. I gave up and went back to a sluice and pick and shovel. My experience is limited and I know that the commercial dredging people work around this clogging. How?

 

[Reno Chris]

There is a whole series of techniques, including not sucking up long rocks, sharp flat rocks near the maximum intake size, etc. Also important is not to suck up too much material too fast. Overloading your intake with material slows down the flow of material as the rock and gravel are dragged up the hose, giving increased opportunity for plugs. You may need to turn up the speed on your engine to get more suction. If you are sucking lots of air while working shallow water, that causes problems too.

Some years ago when dredging was still legal in CA, a friend was dredging and he was getting bad plugs like every 15 minutes (and this guy had been dredging for years). He took a long break for lunch and to take care of some other business, and I took the nozzle for about 3 hours. I think I had one minor plug in the 3 hours and because I wasn't shutting the dredge down and fiddling with plugs, I processed more material faster. I think a big part of his problem was that he was just plunging the intake into the gravel and trying to suck up as much as he could as fast as he could.

 

[steve herschbach]

What Chris said. If you are getting lots of clogs then you basically are just sucking up material waiting for a clog - which you will get. Bars across nozzles are overkill and cut volume way down. I work the material by hand and discard all problem rocks, THEN suck up the material. You can toss them before they clog the dredge, or after, your choice. You learn pretty fast what needs to get tossed and what can go through the nozzle.

Steve Herschbach

 

[machineman]

Keep an eye out for flat rocks. They actually tend to be more common in paystreaks. What happens is that flat rocks go up the hose slower than rounder rocks. then when a round rock comes up behind it they jam together. Try to look at what you are feeding and you will do better. Dredging will move way more material than sluicing. When I started I had a lot of jams, it took some practice to learn how to feed the dredge.

 

[Hoser John]

Pure simple and ez is a BLASTER NOZZLE ia absolutely mandatory. You can thusly leave your nozzle back a bit from the hole,cut through the impacted gravels,melt them nasty clay balls that roll through your box and steal back your gold. Then ez to see what to disguard and you dredge plug up free for days and days no matter what ya run from a tinkertoy 2" to my favorite 10" gravel munching monsters. Ifn' ya ain't blastn' your just a mutzn and a putzn as mandatory for bedrock blastin,clevice bustn' gold gettn' fun. Nothing steals more time,energy and also blasts gold right out of the box than plugups as I get NONE,well maybe 1 a year.-John --OOPS wrong gold pan pic as had one PRIOR to celebration that I ususaaly post and that'n ....welll. lets just say there's a party a going on hahahahaha soooooooooooooooooooooo much fun finding gold by the pounds.....

 

[fastgold]

While on dredging can somebody tell me what the rules are in montana as would like to use high banker with 2" dredge,regards mark

 

[steve herschbach]

From http://www.blm.gov/mt/st/en/info/browse/gold_panning.html

"A recreational miner with a pick, shovel or gold pan does not need a special permit on BLM land in Montana. A person using a suction dredge in Montana should get a permit from the Water Protection Bureau, Department of Environmental Quality, 1520 East Sixth Ave. PO Box 200901, Helena, Montana 59620-0901, phone 406 444-3080. If the suction dredge intake is less than 4 inches in diameter, a general permit is required. If the dredge intake is larger than 4 inches, a more complicated permit is required for which there is a significant charge. The Montana Department of Natural Resources and Conservation and the US Army Corps of Engineers may also require permits for suction dredging.

To encourage better mining methods, the Montana Bureau of Mines & Geology has recently published Special Publication 106, which describes Montana Placer Mining's Best Management Practices. You may also contact the Montana Bureau of Mines and Geology for information on Montana's state regulations and laws. Their office may also be able to provide you with more specific information on gold panning and recreational use. To contact the Montana Bureau of Mines & Geology, write Montana Tech, Butte, Montana 59701, or phone 406 496-4167."

Steve Herschbach

 

[SixHoleBurn]

Does anyone know what Montana's rules on an unmotorized 2 1/2 inch siphon dredge with hose running down stream out of stream bed to a sluice (10 ft from current stream bed) where the water and tails are trapped in an old channel, nothing dropping back into stream, water cleaned by passing trough 10 ft of gravel and entering back in by ground water method? I am putting a 1/2 inch screen over the nozzle and sucking up sand and pea gravel only, moving everything else by hand and a short stout rake. I don't believe I could move more than 4 cu yards a day. I will be tapping into a steep side stream pup, it will give me a 100 ft of head @ 2 1/2 inch necked down to 1 inch, the high pressure one inch will aid a venturi 8 feet from the siphon nozzle. I will "T" it off so I can use the 1 inch for blasting bedrock cracks and chasing it into the 2 1/2 screened siphon nozzle. Any comments would be appreciated.

Thank You; "SIX"

 

[Hoser John]

A righteous blaster nozzel eliminates plugsups quite well. Just move nozzle back a bit as it cuts through clay,impacted gravels and exposes pluggers so you can dredge all day hastle free. Plugs up cost way toooo much time,energy and blast your box--and gold--right outta there. Slower moves much more material and at the end a the day your knuckles don't drag on the ground from wrastln' and a fightn' all day-John

 

[steve herschbach]

I hate to say this but never rely on forums for more than a point in the right direction. Always contact the appropriate agency directly and get answers, preferably in writing. I say this as a person who has done small mine permiiting for over 30 years. I get the basics off the agency website and then I contact the agency directly. I honestly do not look for or pay any attention to "opinions" found on the forums as they can get you in serious hot water. I can also say that I have had little problem with government folks as I never have a chip on my shoulder and I appreciate the fact that the vast majority of them are just people like you and I trying to do their jobs. I communicate often and clearly and ask for help regularly and I get it. Just saying.

If you get stymied on something and are told you can't do this or that, or the rules are too much hassle, just do something else. There is a ton of opportunity out there waiting!

Follow the links below.

From http://www.blm.gov/mt/st/en/info/browse/gold_panning.html

"A recreational miner with a pick, shovel or gold pan does not need a special permit on BLM land in Montana. A person using a suction dredge in Montana should get a permit from the Water Protection Bureau, Department of Environmental Quality, 1520 East Sixth Ave. PO Box 200901, Helena, Montana 59620-0901, phone 406 444-3080. If the suction dredge intake is less than 4 inches in diameter, a general permit is required. If the dredge intake is larger than 4 inches, a more complicated permit is required for which there is a significant charge. The Montana Department of Natural Resources and Conservation and the US Army Corps of Engineers may also require permits for suction dredging.

To encourage better mining methods, the Montana Bureau of Mines & Geology has recently published Special Publication 106, which describes Montana Placer Mining's Best Management Practices. You may also contact the Montana Bureau of Mines and Geology for information on Montana's state regulations and laws. Their office may also be able to provide you with more specific information on gold panning and recreational use. To contact the Montana Bureau of Mines & Geology, write Montana Tech, Butte, Montana 59701, or phone 406 496-4167."

Steve Herschbach

 

[tvanwho]

I run my left hand in front of the nozzle picking out rocks and chucking them, just don't stand behind me.I don't watch where I throw very well.
Also, if you pull the nozzle fairly quick across the gravel instead of going straight down, the nozzle rarely clogs.Every few minutes , take a rake and pull out the cobbles in the hole.
Yes, buy yourself a garden rake , expensive and American Made, them cheap Chinese rakes will bend their tines on you.Rake them cobbles out of the hole.
Don't ferget to keep a piece of steel with you or scrap rebar, bent to the inside shape of your suction nozzle and maybe 16 inches long to knock out rocks. A shot filled hammer with a soft head can loosen up rocks in your dredge hose,or a rock for an emergency hammer.Try not to beat on your nozzle too much as it will dent.Sometimes you can shake the dredge hose up and down to unplug a jam.

-Tom V.