Astrobouncer
Hero Member
- Jun 21, 2009
- 823
- 344
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.
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.
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After that test I changed the spray bars.
I changed the spray bars to conventional ones. I have to keep the amount of water going to the top as minimal as possible to keep pressure up in the bottom allowing it to boil out the lighter tailings. So that's why there's only enough water on the spray bars to clear the gravel and not as much water there as a conventional high banker. It should still be plenty to clear a shovel full at a time (I hope anyway).
Also changed the water hose from the water pump to 1 inch lay flat instead of 5/8 inch garden hose (not pictured cause I was just testing the spray pattern from the garden hose). Hope to get some testing in on it this weekend, but not sure cause I have to Christmas shop too.
Oh and ignore the date on the pics, my new (old) camera wont let me put a new date in it for some reason. Unless I went back in time 4 years to make this and didn't realize it, the pics are from the other day.
Hopefully I can get out soon and do some more testing on it.
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.
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.
----------------------------------------------------------------------
After that test I changed the spray bars.
I changed the spray bars to conventional ones. I have to keep the amount of water going to the top as minimal as possible to keep pressure up in the bottom allowing it to boil out the lighter tailings. So that's why there's only enough water on the spray bars to clear the gravel and not as much water there as a conventional high banker. It should still be plenty to clear a shovel full at a time (I hope anyway).
Also changed the water hose from the water pump to 1 inch lay flat instead of 5/8 inch garden hose (not pictured cause I was just testing the spray pattern from the garden hose). Hope to get some testing in on it this weekend, but not sure cause I have to Christmas shop too.
Oh and ignore the date on the pics, my new (old) camera wont let me put a new date in it for some reason. Unless I went back in time 4 years to make this and didn't realize it, the pics are from the other day.
Hopefully I can get out soon and do some more testing on it.