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View Full Version : Wanting too expand. Ideas for a small washplant please

08-29-2012, 04:50 PM
We have a smal two person operation. We started with sluices and have worked are way up to a 4" dredge (Federal Claims). Last year the State added the stream we work to the Anadromous stream catalog. So now we are more limited in our dredge activities.

I am not opposed to bringing in some small equipment and a washplant to make our season last longer and to work more ground. I would like to stay small. I know I can't push allot of dirt with a Bobcat but that is the size of machinery I would like to use. We are remote and on a cub strip. So any equipment has to come in, in the winter.

I would like to have some advice on a trommel/washplant that can be fed with a mini excavator or a Bobcat size loader. Something that can be moved without too much effort would be a plus.

We do not have very deep overburden. The biggest pice of machinery we would want to use would be something along the lines of a D6 dozer.

Any advice on what has worked and what hasn't is appreciated.

08-29-2012, 08:06 PM
what is your material like ( smaller gravel, big boulders ..etc )? Gravel pay or all bedrock? What is bedrock composed of?
What is your idea of "we do not have very deep overburden" ?
Little more info and I'll give you my opinion.

08-29-2012, 08:35 PM

We have what I consider small gravel. Hardly any big boulders. Even our high benches have old river rock with decent pay. Bedrock is a hard pan layer. We do have a clay layer that traps allot of the gold, if we run into the clay we have found it to be not as productive to go beneath it. Our overburden is either surface to three feet. We have some old tailing piles that need to be worked over too.

08-30-2012, 12:16 AM
I have a trommel im building 80% built that will be fed by a ex40 (1/4yd. bucket) My plans are to be as portable as possible. I want to move the trommel up the creek with the hitachi as i go. Drum is 18"x9ft. I am rolling it with a honda 4hp with a gear reduction on it. My sluice is 18"x8ft. Sluice is parallel to drum so i wont have any tailings in the way of advancing up the creek. I will need grizzly bars on my small hopper which will eject to a trough also parallel to the drum to eject out the back. Anyways theres alot of ideas out their on smaller trommels. I want compact, maybe 8-10 yds/hr. Are you building or buying a trommel/shaker screen? I have less than $2500 in mine.

08-30-2012, 07:08 AM
I wanted to buy. I have looked at several portable trommels. And that was the problem there are so many out there and I would like to buy one not several. For example, I wish I would have just started with a 4" dredge rather than slowly buying smaller ones and working my way up.

08-30-2012, 07:31 AM

I've been there - done that. ("T" shirt included). See www.ophir-alaska.com for the details! :)

- Geowizard

09-02-2012, 07:34 PM
We finally built a trommel for my washplant, due to ineffective operation of the grizzly, which was several modifications from start to finish, and it really needed to be tossed, and started over. FOR ME, if I was to do it again, I wouls concentrate on making a grizzly that had angled screens so that it used gravity to take out large rocks as the material all went down through three angled screens (sand pit type screens or parallel rebar), and then fell into a small trommel with the last material being 1" or less. One of the biggest wastes I have seen is using a lot of water to move and wash unproducing cobble and rocks. Make it down and dirty simple, and use minimal water, unless you have a fresh water source, and can return it to a pond or off flow without getting into expensive remediation. It doesn't take a lot to wash gold off rocks unless you are in a clay streak, and if you can get it to fall through a screen into a finer classifier, it reduces the fuel cost a lot. Let gravity take care of rock disposal. Sure, you may eventually have to use a loader to move them, or maybe you can make it on a slope that will give you natural gravity disposal for a very long time until you have to clean it out.