Bucket highbanker with hydraulic/fluidized bed riffles

[astrobouncer]

When prospecting mobility is important when you have to get off the beaten path and its a hard hike to gold bearing gravels. Sometimes its just too far to hike in while rolling a conventional highbanker or coming down a mountain or steep grades. So I built this bare bones fluidized bed highbanker/concentrator for about 50 bucks. It would have been much cheaper, but I underestimated how many square feet of rolled steel I needed for the grizzly. I ended up using 13 bars @ 3 bucks a bar. The rest of the cost was for the PVC pipes (mostly the 2 flow adjustment ball valves).

I built this in about 2 hours, and then tested it for only 30 minutes. I know it needs much more testing and the spray bars are not final.



Here's putting the pvc together to make the hydraulic/fluidized bed riffles for the bottom spray bar.





There are 5 bars, with 6 spray holes on the bottom each a little smaller then 1/8 inch. Sorry I forgot to take a pic of them. 


The fluidized bed trap is 6 inches deep by 10.5 inches wide however, after testing I think the trap is going to need to be shallower in order to pump out the tailings easier. 







These spray bars are just something I was trying, I am going to build regular spray bars like on a conventional high banker. These did not cover the area enough to wash the gravels well.





Here's how I made the grizzly, this was Dr Phils idea and it worked great. Just a bunch of bent rolled steel. Then I drilled holes in the bucket to slide them through. They are removable if needed and I might need to strengthen the bucket on the bottom part where all the gravel slides.





I used about a 3/8 inch spacing on the grizzly but a couple of them went slightly larger (to almost 1/2 inch). I intend to make a 4 mesh hardware cloth grizzly to fit over that when I want to classify smaller.




I cut all these with a hack saw and measured each one out so it would fit right.













Here's one of two ports for tailings. The tailings come out either side on the back. They are about an inch high so they cant get plugged up. The lighter material constantly boils out of these while running (and the heavier stuff settles deeper into the slurry). 





Here's my small water pump next to the bucket highbanker. I have used this pump for my bigger highbanker as well.  That pump is nice and lightweight and easy to carry, only rated at about 39gpm at full throttle but that's more then enough water for either high banker.   





Here it is all ready to take for some testing.



And next to my main highbanker.




Now time to hit the creek for some testing.











To clean it up you just turn it sideways and let the water pump it into another bucket. Or you can just carry it out as it sits when you turn the water off.

I think it worked pretty good for a first test run. Here's the cleanup pics. It caught much smaller then 100 mesh as well as anything bigger. I only ran about 25 shovelfuls of material because the top spray bar needs regular bars for better washing of material. 






So what did I learn? Well it does work but I need to redesign the trap to either be shallower and/or increase the flow coming out of the bottom  water bars so it flushes out the lighter stuff easier. Right now its holding too much blond sand which means you have a lot to pan out when its time to clean up. A smaller trap would alleviate that. Also since the trap is so big it holds a lot of black sand, which makes it really heavy to carry out without first panning it down further. And obviously the water delivery method for the grizzly is not done. I am going to put some conventional top and side spray bars on soon as well as make it out of larger diameter pipe. 

[idled]

I was thinking about putting some thing like that together as well. But using a square pail and putting a slick plate under the grizzly.
So that the con would enter the fluid bed on one side and the blonde's and lights would exit on the opposite side.

[TroyB]

Cool build Astro.
Like to see a video of it in action.

[sulcata99]

Great build and a cool idea! You may not want to make the trap shallower, it will hold more heavies as is and you wont have to clean out very often. Might even get a full day out of it!

[heartlander27]

Cool build. I like the idea of keeping the bed still, without water flowing horizontally over the top.   

[NickMarch]

Good job astro!

I like anything original and not ordinary! 

If I may a few suggestions from my out of the ordinary mind...

Fluidized beds work best if the water is delivered thru the bottom.  You can use two buckets instead of one to accomplish this. 

Put a bulkhead fitting in the side of the bottom bucket to deliver the water into the system.

Drill holes in the bottom of a second (top) bucket and put the second bucket into the bottom bucket.  You will need to anchor the top bucket to keep it from rising under pressure.

You may also be able to drill holes into the sides of the top bucket to spray the grizzly bars??? 


Nick

[muconium]

Right on Astrobouncer... My creative-winter-thinking has been heading in the same direction: Spraybars and grizzly feeding into a fluid bed that uses this design from the "fluid-bed thread" at another forum:

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I'm on the fence about whether to use a fluid bed or a drop riffle sluice. Sluice highbanker means less plumbing work, but a fluid bed can be fed faster...   

[PlacerWilly]

 Really Neat astrobouncer !
Thanks for sharing and I look forward to more tests and such !
Well done 

[sulcata99]

How many shovel fulls a minute do you think it will run?

[ebuyc]

I like this design a lot!    

What is the difference if any between the fluidized bed and an elutration tower? (I think that is what it is called - like my quicksand concentrator)
In the quicksand concentrator it is a vertical pipe that suspends and pushes out the lights... (versus the fluid bed horizontal design)

I want to see more of these!  

Pros and cons? Anyone?

Yep need more input so I can build something like this too!