Steve Herschbach

Wash plant for mini excavator

34 posts in this topic

There is an amazing array of mini excavators on the market, and many can be had for less than the cost of an 8" suction dredge.

But there seems to be a real lack of wash plants designed to work with these small units. There is a huge gap between shovel into highbankers, and the big wash plants.

So what is there that can easily take the feed from a 1/4 yard bucket? Straight up oversized highbanker or small trommel. I know from experience the Proline Big Banker is too small. Need something at least twice that size. Preferably on a trailer.

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There are a few pieces in the category - but you are right, not a lot of them. Take a look at page 7 in the March Issue of the ICMJ. Its made by the folks who build the gold claimer and while the Goldclaimer itself is too small for what you are talking about, they make a "next size up" unit and I thnk that would handle what you are talking about and its trailer mounted. Goldfiled International also makes some smaller sized units.

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Steve/Chris: Met you both at Alpha/Omega a couple of summers ago detecting w/Mark and mike... ck out Heckler Manuf. in Roseville, Ca, and

McKirk in Idaho.. both have portable plants that could handle mini-hoe feeds... me, I'm just a wheelbarrow n' shovel guy trying to stay low profile,

praying for the opportunity to run my 8" subsurface one final time!!! regards, allen

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I bought a Gold Claimer, the smaller one, and I know a guy we both know who has experience with a larger one. My main comment - NEVER use a conveyor belt to feed a washplant. Remove the rocks after washing, as in a bucketline, yes. Feed material, no. You need to be able to dump directly onto a slick plate and then into a trommel or grizzly/sluice.

 

Many moving parts/valves/actuators = bad. Minimum moving parts/valves/actuators = good.

 

Heckler and Angus are in the ballpark. Wonder if these guys ever visit real miners? If the trommel is made right you do not screen ahead of the trommel - that is what the trommel is for! A grizzly ahead of the trommel makes a pile of large rocks on one end, then you get medium rock on the other end, then you get sluice tailings. Should be two piles - the big rocks coming out of the trommel and the tailings out of the sluice. The trommel should handle anything that will fit in the 1/4 yard bucket. The bucket is the initial screening device.

 

A grizzly on the trommel is just making up for an undersized trommel.

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Ron,

  That M50 is not a bad looking little plant. I think real close to what Steve is looking for.

Must say I did not care for the way it feeds directly onto the shaking deck. Quite a shock

to that poor shaker!  I would place a short, fixed feed plate/hopper before the shaking deck.

 Anything just to take the initial load shock.

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Dick - good point on the feed entry - I would also put some side pieces on as well just to minimize spillage (cleaning up around a screen / conveyor / rock crushing plant with a hand shovel and wheelbarrow is a pain (I've done it)

 

I watched the video and the other thing that concerned me was the single curtain of spray wash. If you have nice clean river rock with a minimum of clay, you might be OK, but if your material needs a good washing, I dont think a single spray curtain maybe 6 inches wide will give the kind of comprehensive washing needed for cleaning the rock, breaking up clods and getting all the fines into the screen. It looked like a lot of water was coming down in that short section, but I'd rather see it spread over a distance while the material is on the screen deck. Probably wouldnt be that hard a modification to do to add more sprayers.

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Just below my claim, there is a couple of people using one of those GWP plants.  They expressed to us that they were having problems on welds somewhere on the chassis of the plant.  The company though was working with them and it sounded like they maybe just had a bad unit or something.  Nice looking shaker though.  

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Chickenminer and Chris,

Thanks for the information. I learn a lot from your experience. I will just be dredging a bit in the summer for the next 4-5 years, but this knowledge will be useful when/if I take the next step.

Ron

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Not to hijack the thread but what about a wash plant for a skid steer loader? Preferably with a trommel. We have lots of clay.  I know on previous forums it was discussed about the "jerky" unloading of a skid steer bucket.

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The whole idea behind a presizeing classifier is to remove large boulders that beat your equipment to death in a very short time. As anyone with trommel experience can tell ya you CANNOT build a plant sturdy enough to handle anything you throw at it or you can't make that 10 ton behemouth roll-think idjet Hoffman and his super trommel on tv show--that never worked as toooo big and tooo heavy. Look at all the other ops also as 1 wrong boulder kills it all.John

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Lots of commercial trommels are fed directly from bucket to trommel. There is absolutely no reason that a mini excavator or Bobcat cannot feed directly into a trommel via a slickplate. Nobody is suggesting putting "boulders" through the trommel. Just material normally handled by a very small bucket.

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John - trommels as big and bigger than the one installed by the Hoffmans work all the time and work well - so long as they are properly operated. Big trommels can work fine - anyone with trommel experience can tell you that's a fact. That trommel failed because it was a poor version of a reverse helix design that depended on a rubber wiper to sweep the gold uphill. The flimsy rubber failed almost immediately and they probably got less than 10% recovery on the gravel they processed with it. However, it did not fail just because it was too big and heavy.

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This is looking more like it:

 

plant.jpg

 

"A hopper fed pay into a 3½ -foot diameter by 12-foot long trommel. Eight feet of ½ -inch screen classified the pay gravels before being sluiced. The ½ -inch minus pay passed over two boil boxes before being sluiced through a single sluice run 6 feet wide by 5 feet long."

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No one is perfect and BIG boulders do get by and ruin equipment,seen it 1,000s a times. In Carson City behind the airport off conestoga is/was a huge trommel builder who I visited regularly as ran a plant periodically 2 doors down. He was constantly repairing abused equipment from running too big a boulders through them. The direct proportional ratio of weight/size in conjunction with the of rate of spin magnifies the g forces expotentionally smashing into the barrel agitators. This effect is EXACTLY akin to hitting a wall at 5 mph in a vw vs a mack truck.All the ops on ak show killed washplants that a way or was that staged too hahaha yep never happens-John

Alaska Range Miner likes this

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I am a bit doubtful that a mini excavator or Bobcat operator is going to miss that kind of big boulder. I guess it could happen, but lets just put that aside for now.

I agree Dick, little rigs like this would be the way to go. Pretty much looks like you have to custom make them though.

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I had a welder slap some 1/8th in.steel together in a 24x24 square,put a 12 in. channel out the front to feed a 8 ft aluminum sluice.Grizzly in the spray at an angle and tiltable to get rid of the big ones after washing.Feed with my mini just fine

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I forgot the part where the grizzly extends out of the wash box far enuf I can bounce it with my bucket to get the big ones out.After I move the box to another location I metal detect the the big rock pile.( yeah we have nuggets that big)

 

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 I have been feeding a small trammel plant running 3/4" minus tailings. The plant runs 20 YPH about right. I am feeding it with a 312 Cat excavator and a one yard bucket that I load a half yard in. Even with the thumb I am thankful for the grizzly bars. There are  a few large rocks in these tailings and I don't want a soccer ball size rock going thru my plant. I have fed thousands of buckets into trommels for different mines over the years and it is a very boring job. Its very easy to miss a rock that you would rather not have go thru your plant. We are screening to 1/4" minus thru the trommel then to a sluice that dumps onto a sewer plant screen with a vibrator that screens down to -1/16". That material then goes to two vortex bowls for the fine gold recovery. It is working well. Where it is tailings we are running there is no need to wash the large rocks. A couple of times a day I get a surprise and a rock will hit the grizzly bars. After a few 14 hour days feeding the plant it is pretty easy to miss a rock even in a small bucket.

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The yellow one Dick showed looks neat and very portable but any clay will ball up and take ur gold, seems it doesn't have agitators (looks like screen all the way to the entry end) No grizzly and no agitators, maybe big rocks wont tear it up but the weight of a 70lb rock missed in ur 1/4yd bucket might wear the screen way fast! So, I just went out in the Alaska winter snow and measured my hitachi ex40 excavator bucket. inside measurements 23" wide x 23" tall x 16" deep. Rated at 1/4 yd. So heaped would be lets say 30" deep. If this thread is really for a mini excavator, I don't see how to make a "small" trommel without a grizzly that will not be short lived. Take a 6" dredge for instance, look at the cobbles you put aside in one day that didn't go thru the nozzle, now imagine running 5 times that amount through a mini sized trommel. Good luck, ive been a welder/fabber at a coal mine on 35yd dragline buckets/all equipment from d5-d11 dozers and kept processing plant going (producing 2m tons /yr)

 

 Steve,

   I understand exactly what you are trying to do here, I have the claims, mini ex and have been reading, studying, looking at many samples of trommels, and have drawn up and slowly been building my portable processor. I want to dig creek, process and move trommel up creek with pintle eye on mini blade as I go. Problem is I really need just 2 piles at the tail end like you suggested. So the grizzly needs to dump to the side and slide down a chute(half pipe) just parallel to the trommel. My main objective is to keep my costs small and keep this at the edge of a hobby so I can enjoy an not feel the burden of expectations! No employees, just me and maybe wife or one of my kids.(I gotta have someone to boss around!!) Anyways, my thoughts.     

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