Micro Dredge?

[Dogbite]

It does this.
It draws 14 amps.

 

[Toecutter]

View attachment 1773340

I made this. It weighs 14 pounds. The 35Ah battery weighs 8 pounds and fits in back pack.

Well that little feller is cool...Have you had success with it? What kind of problems have you ran into?

 

[brianc053]

Back in 2015 there was a thread about the Goldsnare SGS-2 and I commented on the little brother version, the SGS-1. http://www.treasurenet.com/forums/sluicing/485313-goldsnare-sgs-2-a.html
You may find that thread interesting.
I commented back then because I bought the SGS-1 and used it....for a while. My key quotes from 2015:
- it works in the right situations (but today I would say that those situations don't come up too often)
- it doesn't move a lot of material (and this was the big drawback for me).

Today my SGS-1 sits in a bucket up on a shelf and hasn't been used in years (if anyone wants it, send me a PM).
If I were backpacking into a remote area I would take a shovel, sluice, bucket, classifier and pan.
The SGS-1 would only go with me to very specific locations where I wanted to clean out certain cracks that were far enough (but not too far) underwater to give me room to utilize the SGS-1.

MacgyverMike please factor this in with the other comments about the ineffectiveness of micro dredges. I've formed the opinion that they're too specialized (though I understand that you have a specialized situation you're trying to address).

- Brian

 

[Dogbite]

Success yes.
Problems yes.
Lots of time and money yes.
Happy to share yes

 

[Dogbite]

Macgyver, I was going to start my own post when I ran across your wish list and decided that this would answer your questions.
I have been working on this problem specifically to address both performance and portability issues to access areas too deep for just a shovel and bucket.
It is a 1 inch I.D. suction nozzle with a handle to allow for probing into deeper areas.
The sluice is 5 inches wide by about 18 inches long.
Almost everything has been handmade and field tested over the past 1-1/2 years.
Happy to post pics and answer all questions. No secrets.

 

[Dogbite]

Have made improvements and a video.
The rig works well and enables me to search in areas that have not been worked over. Weighing in at just over 16lb. it is very portable and effective. Run time over 1 hour. Still working out bugs but lately have been spending more time concentrating on washing gravel and less time fixing equipment. It traps very fine dust and small flakes very well.
Enjoy

 

[Dogbite]

Improvements to te nozzle injection reduction assembly. The injector is 3D printed and is removable and can be modified.

 

[N-Lionberger]

Improvements to te nozzle injection reduction assembly. The injector is 3D printed and is removable and can be modified.

Holy crap man. I get DIY but man with the 3D printing you should be doing something more interesting than a device that’s been made by everyone. You could try multiple jets with different jet shapes. My 4” has a Vortexrex quad jet it rocks.

 

[russau]

I really liked my VORTEXREX Jet that Dave sent me maybe 20 years ago or so !I hated getting rid od it BUT the dredges had to go if I couldn't use them anymore ! Old age does have it's own faults !

 

[Dogbite]

Holy crap man. I get DIY but man with the 3D printing you should be doing something more interesting than a device that’s been made by everyone. You could try multiple jets with different jet shapes. My 4” has a Vortexrex quad jet it rocks.

I have thought of adding a twist in the output of the 3d printed injector nozzle but was uncertain if there would be any benefit other than it possibly tightening up the stream like rifle adding twist to a bullet to make it fly straighter. Rember the inlet is only 1 1/4" id so not much room to work multiple jets. The rig is electric and only capable of about 12 psi output. Have been trying different bore sizes to optimize performance.
On a recent outing I achieved 3hr plus continuous run time and managed to proscess an amazing amount of material. The driving factor behind this was the portability to enable traveling to areas that are less accessible and less worked over by others.
Never really found much online about this subject other than a few glimpses that were helpful particularly about nozzle design. Thanks for your input.

 

[njcommercialdiver]

dogbite, can you post some more pics of the outside of your bucket like the inlet side with the classifier, does it discharge outside the bucket?

 

[Dogbite]

These are pics of the inlet end and the classifier. The classifier is removable for periodic cleaning by literally banging the screen on a rock and rinsing in the river. Tailings from the classifier are dropped out the back. These are pictures of a more recent version.

 

[Dogbite]

Yet another version in action and you can see gravel falling off the classifier screen

 

[Dogbite]

And a video too.

 

[N-Lionberger]

You can rifle the water inlets that is something that has been discussed. If you can cause the water to spin in a pipe it reduces the friction. The old timers riveted fins into their hydraulic monitors to make the water jet more efficient.

 

[njcommercialdiver]

nice work, does the pump in the bottom just suck water thru the sluice discharge cutout?

 

[Dogbite]

nice work, does the pump in the bottom just suck water thru the sluice discharge cutout?

There are two pumps. One for the wash spray and one for the suction nozzle.
The pumps pass through the bottom of the bucket which greatly helps lower the center of gravity to gain flotation stability.
The pump intakes are protected with the second bucket bottom that is shown.

 

[njcommercialdiver]

nice work, might have to blatenly pilfer your design, theres places in my bosses creek that is a pain to dredge since they arent deep enough to dredge at normal water levels. i have to put a tarp with logs underneath and build it up across the creek where i want to prospect to create a dam and when it backs up i can drop one of my small highbankers in, otherwise i have to pump water in from a couple pools away . i could use this for some of the smaller holes id like to check out without the "engineering project" i normally have to do

 

[njcommercialdiver]

this is where i play, all these rocks are volcanic diabase and got moved here by glaciers from canda. most times, i find only a couple flakes, one day i walked up here and took 6 shovels of material and ran it in my wheel, got 3 flakes out of those 6 shovels worth

 

[Dogbite]

this is where i play, all these rocks are volcanic diabase and got moved here by glaciers from canda. most times, i find only a couple flakes, one day i walked up here and took 6 shovels of material and ran it in my wheel, got 3 flakes out of those 6 shovels worth

NJ,
Definitely a different environment than the one I visit. Please be free to use and mabey improve my ideas, they have proven to work for me in several different environments around town here.
The river is clear creek west of golden Colorado. It was cold today.