Anyone use a plastic gun case for a sluice box either wet or dry?

Got lucky at an estate sale and got the following for very little cost that I believe will work for one box that is both 110 / 220 volts:

13 gallon 1 HP High Flow Dust Collector

https://www.harborfreight.com/13-ga...llector-31810.html?_br_psugg_q=dust+collector

Also will play with the following for more than one box at around 23 percent off:

35 Gallon, 2 HP High-Flow High-Capacity Dust Collector

https://www.harborfreight.com/power...-flow-high-capacity-dust-collector-59726.html

I hope my projects are not just a 'blow over' with all the wind within...........LOL.
 

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Well even if the box setup does not work exactly as I hope and plan. The pre tests show that there is a fast and clear separation of the different size materials. This set up will pay for itself as just one of the steps to classify the different size materials if nothing else. There is at least a reasonable concentration of the heavies as well with the process.
 

Some info to chew on:

Dust particles fall at a speed of about 100 millimeters/second or roughly four inches per second. Particles larger than 20 micrometers in diameter fall disproportionately faster: 50-micrometer particles fall at about 500 mm/s or half a meter per second.

Wind speeds in larger dust devils can reach 60 mph or greater.

Median forward propagation speed: 22 mph. Maximum speed: 37 mph.

Note that the speed of sound is largely determined by how fast the molecules move between collisions, and not on how often they make collisions.

If we consider the atmosphere on a standard day at sea level static conditions, the speed of sound is about 761 mph, or 1100 feet/second.

Wind Tunnel Index NASA

https://www.grc.nasa.gov/www/k-12/airplane/shortt.html

Drag exerted on the particles by the continuous gas phase is the key force component. The drag is related to the updraft speed. Stronger the updraft, the more drag to lift solid particles.

Individual soil particles generally need to be less than one mm in order to be moved by wind. Individual clay particles have an average diameter of only 0.001 mm but they usually clump together in aggregates that are too heavy to be moved by wind.

produce peals of sound at very high frequencies—between 500 and 2,500 hertz—lasting less than a quarter of a second.

Sound speed values at room temperature range from 1.474 km/set for a red medium clay to 1.785 km/set for a medium sand.
 

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well people, I think I've finally accomplished what I set out to do 8 or 9 years ago. I think I've built at least a dozen different machines in an attempt to get something I could use to recover diamonds and indicator minerals without water. Maybe twice that many. The number of hours I've spent thinking about this are countless. I had an idea that my dry sluice might finally hold the key. I recovered a few tiny garnets with the larger model in Wyoming last summer. But, I still wasn't convinced. The riffles weren't quite right, and tiny gems are easier. Today, using the backpack model which only has a 7" x 24" sluice, but with the new riffle design, I put 8 1/4" alumina abrasive spheres in 3 gallons of mixed dirt/gravel. About 20% gravel, and 80% dirt/sand.silt. The alumina spheres have a specific gravity of 3.5. In most of the west the SG of the background material is about 2.5. I've never before managed to separate anything of less than 10, or a 1:4 ratio. All 8 stayed in the sluice. That, for me is a real accomplishment. I think the combination of that riffle, and the particular motion I designed into the sluice has finally overcome the "Granular Convection" problem. This is going to open up a lot of gem country, where previously I had to screen, classify, haul buckets of gravel to a water source, to use the Pleitz jig, etc. I'm a happy camper this afternoon. And, it should work even better on heavy metals. I'm going to apply for a Provisional Patent to start with.
Jim
 

Well I hope it does not take me many years of playing around with my dry box set up to get reasonable results. :dontknow:
 

Well I hope it does not take me many years of playing around with my dry box set up to get reasonable results. :dontknow:
For metals, it ain't rocket-science. But gems are really difficult. The problem is what is known as "Granular Convection", or the Brazil-nut effect. You should research that if you're after gems. If only metal, you'll be fine.
Jim
 

For metals, it ain't rocket-science. But gems are really difficult. The problem is what is known as "Granular Convection", or the Brazil-nut effect. You should research that if you're after gems. If only metal, you'll be fine.
Jim
I agree as the goals of catching metals come first.

With that being said I wondering with your vent idea if I could come up with a reasonable zone area for some gems to start showing up?
Especially if the boxes are long enough for some interesting zones and turbulence areas for a good drop out.
 

I agree as the goals of catching metals come first.

With that being said I wondering with your vent idea if I could come up with a reasonable zone area for some gems to start showing up?
Especially if the boxes are long enough for some interesting zones and turbulence areas for a good drop out.
The deal with gems is the fine material "floats" the gems. Granular Convection is the issue of small particles floating larger particles. So no matter what you do, if you have smaller particles than the gems you want to recover, the gems are going to be lifted into the tails stream, and go out. The nickname Brazil-nut effect comes from the packaging industry because of canned nuts always having the larger nuts at the top of the can. That industry has done a ton of research into the effect without solving it without really expensive machinery. From the research I've done, nobody seems to have a solid explanation for why it happens. Lost and lots of theories on it, though. Water greatly diminishes the effect, so mineral jigs still work. Working dry is where the issue really becomes a problem.
Jim
 

Water greatly diminishes the effect, so mineral jigs still work. Working dry is where the issue really becomes a problem.
The hydraulic effect between the particles / rocks will almost keep them apart most of the time.
That industry has done a ton of research into the effect without solving it without really expensive machinery. From the research I've done, nobody seems to have a solid explanation for why it happens.
Very difficult to measure what is going on due to the fact that the different minerals are osculating / frequency movement, each different from each other in the general mixture.
 

It really isn't an issue with the type of mineral...it's all about physical size. Little stuff floats big stuff. Even in farmer's fields around here, the occasional basalt boulder comes to the surface. My experience has show you need a very minimum of a 4:1 density ratio to even start to overcome it.
Jim
 

It really isn't an issue with the type of mineral...it's all about physical size. Little stuff floats big stuff. Even in farmer's fields around here, the occasional basalt boulder comes to the surface. My experience has show you need a very minimum of a 4:1 density ratio to even start to overcome it.
Jim
The critical thing to remember about quartz is that it's piezoelectric. It will vibrate when you put electricity to it, and it is going to give you electricity when you vibrate it. The quartz crystal oscillator uses piezoelectricity in both directions — at the same exact time.

I'm thinking that the physical size of a given mineral particle can over come this electric force affecting it from the quartz mineral as a example.
 

Then there is
Igneous monzanite crystals

The mineral monazite, a uranium- and thorium-rich phosphate of a rare-earth element (REE), is a common accessory mineral in a variety of felsic igneous rocks and is a common trace constituent in many metamorphic rocks, particularly metapelites.
 

There is other minerals as well. However there sure is a lot of quartz in nature.
I'm thinking that a lot of "Hot rocks" could have similar traits as well.
 

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Monazite is a paramagnetic mineral that can react in a magnetic field at an intensity of about 1.5 teslas.
All you need is some electricity flowing near by and this mineral will be moving around on you or the inside of equipment.
 

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Anyone use motion frequency with a air flow tunnel?
 

Well I located a new tool to play with and that is a mortice drill press. So rather then destroy a good gun case up front.......... :blob8: :BangHead::icon_thumright:..............I will make square holes in wood plank as the different catch traps to start playing with first. The plank will be a small wind tunnel at different angles to start playing with.
 

Well the plastic case idea is looking better with the concept of using different catchers and mats for the different size values and making different run batches for that reason depending on the particle size you are trying to catch. Just don't want to make the jump yet as there has been snow and cold lately.
 

Years back (20 ??) I had a conference with a man named Phil Hontz from Albq. New Mexico. He set me up on a friends site for dry washing for finer gold particles. And when building my Blower Dry washer he said to paint the hose that fed the air to the dry washer BLACK to help induce heat and Static electricity to the air flow to my DW to assist in the capturing the fine gold . I did so BUT I needed more length to my hose to help raise the temp and the Static ...... We were only out there for 2 weeks and it was the only time I got out there. It helped but I needed to slowly are material to my hopper to keep from hogging the material . The idea worked for me .
 

Yup....dry air thru the silk fabric creates static electricity, and that makes the gold cling to the cloth. Works, too.
Jim
 

Another approach for the concept of drying materials out is multilabel turning over or stirring up the same general material over and over. If heat is needed some fuel can be used to speed up the drying in this process.

With this approach in mind why not run the material a number of times with the idea of pulling out the courser size values first then keep going smaller and smaller each run batch.
 

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