Noob Highbanker / Sluice advice needed - Videos

[ethought]

Hi All -

I just got my first highbanker (prospectorschoice with 1200gph pump) a few days ago and took it up to one of the local prospecting areas near where I live.

After watching many videos on Youtube about how to set up and operate a highbanker /sluice I thought I was ready to get it right. Getting out there and trying it out it quickly became apparent I have much to learn!

I took 2 videos of the highbanker in action:

The first, shows the unit with fresh (as fresh as I can get) water and the second after I had run a bucket or two through the unit.

I found that even after half a bucket was run through the unit filled with small rocks, sticks and plant matter and seemed to really slow down the water flow. I had to clear the rifles regularly with my hand.

I know they are not really the best videos and the murky water makes it quite hard to see whats going on but can anyone give me some pointers on what I could be doing wrong? Is the water flowing too fast, too slow, wrong angle?

I got about 5 tiny (barely visible) flecks of gold from about 9 buckets of material and was cleaning out after every 3. I was running material that was lying around old mine shafts (mullock heaps) which as far as I know has never seen a sluice before. The thing is I have panned material from the same place before and got more from a few pans than I ended up getting all day with the highbanker so clearly I am not doing something right..

 

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[maverick41950]

Nowhere near enough water. That is my opinion but we all know how opinions go.

 

[ethought]

Nowhere near enough water. That is my opinion but we all know how opinions go.

Hmm, that did cross my mind as well. The strange thing is that they sell this highbanker with a choice of 3 different pumps: 500gph, 800gph and 1200gph. So I got the 1200gph thinking it would be sufficient.

Could it be the 1200gph pump that I got is not actually running at anywhere near 1200gph - i.e. bad pump?

The listing on eBay for the 500gph one even says any more than this and you will lose fine gold through the unit?!?

In general if I had a more powerful pump like 2000gph or even 3700gph would that be too much for fine gold recovery?

 

[Goodyguy]

The biggest fault I see is not enough GPM for the design, next the riffle height is too tall for the gpm, then to make it worse the sluice gets wider at the discharge end lowering water pressure that much more.

I went to their site to see what their thinking was and my opinion is that they have it wrong. But as Maverick stated we all know how opinions go.

My suggestion would be for you to pre-classify your material down to at least 1/4" before running, and increase the angle to try and make up for the design and gpm shortcomings.

GG~

 

[ethought]

My suggestion would be for you to pre-classify your material down to at least 1/4" before running, and increase the angle to try and make up for the design and gpm shortcomings.

Thanks for the suggestion Goodyguy, I will try classifying and running the unit at an increased angle.

I did actually try running at an increased angle and it cleared the riffles much more efficiently but I thought I read somewhere that running at more than 1" drop per foot would cause gold to pass right through. Is that not so?

 

[Goodyguy]

Thanks for the suggestion Goodyguy, I will try classifying and running the unit at an increased angle.

I did actually try running at an increased angle and it cleared the riffles much more efficiently but I thought I read somewhere that running at more than 1" drop per foot would cause gold to pass right through. Is that not so?

It's all relative. Some designs require more drop than others. I have one design that requires 3" per foot (1" tall riffles) and another that requires only 1/2" per foot (no riffles).
When the sluice is setup properly the riffles will not load up. But if they clear too fast then either there is too much drop or else too much gpm.

Try angling 1/2" at a time until it works properly for the material you are running. No matter what, I would classify down to at least 1/4" before running.

And always check your classification tailings for nuggets just in case.

GG~

 

[Doug Watson]

I don't like expanded metal for the grizzly as it seems that everything hangs up on it and it's hard to keep clean.

 

[Fullpan]

Looks to me like about 50 gpm(300 gph approx), when it should produce about 200 gpm. - Try the pump at home, using clean water -

 

[ethought]

Looks to me like about 50 gpm(300 gph approx), when it should produce about 200 gpm. - Try the pump at home, using clean water -

Thanks Fullpan - I assume you mean it looks like it is running at 5gpm not 50gpm (which would be 3000gph)..

I will run it with fresh water at home tomorrow and make a video and post it on this thread.

 

[Goodyguy]

Thanks for the suggestion Goodyguy, I will try classifying and running the unit at an increased angle.

I did actually try running at an increased angle and it cleared the riffles much more efficiently but I thought I read somewhere that running at more than 1" drop per foot would cause gold to pass right through. Is that not so?

One thing for sure is that once your riffles are loaded up fine gold will wash right on down and out the end.
And the larger gravels will also knock fine gold loose as they bounce down the sluice.

Any stop and go by the flow of water will lose fine gold as well. When the water flow stops you will see trapped material move out from under the riffles. Then at startup any loose gold could get washed out by the sudden blast of water. If you must stop the water flow then either do a cleanup or gently increase the flow of water.

Also don't use your fingers in a raking motion to clear loaded up riffles. It's best to just pick out the larger gravels or stop and do a clean up.
Once your finger enters the flow it creates a danger of loosening up fine gold due to the increased water pressure around it.


GG~

 

[ethought]

Any stop and go by the flow of water will lose fine gold as well. When the water flow stops you will see trapped material move out from under the riffles. Then at startup any loose gold could get washed out by the sudden blast of water. If you must stop the water flow then either do a cleanup or gently increase the flow of water.

Also don't use your fingers in a raking motion to clear loaded up riffles. It's best to just pick out the larger gravels or stop and do a clean up.
Once your finger enters the flow it creates a danger of loosening up fine gold due to the increased water pressure around it.
GG~

Thanks again Goodyguy - that is some valuable information for a noob like me. I was processing a bucket of material then shutting down the pump and going to dig another bucket of material and noticed there was a bit of a surge everytime I turned the pump back on to process the next bucket. I will now get a few buckets ready and run them all at once then stop the water flow then clean up.

And to clear the riffles I was raking my fingers through to loosen up the gravel, which I will stop doing now.

Just to be clear, when the high banker is running properly should there be no build up of material infront of the riffles? In other words by the time I get to clean up should there just be black sand and (hopefully) gold behind the riffles?

 

[Goodyguy]

Thanks again Goodyguy - that is some valuable information for a noob like me. I was processing a bucket of material then shutting down the pump and going to dig another bucket of material and noticed there was a bit of a surge everytime I turned the pump back on to process the next bucket. I will now get a few buckets ready and run them all at once then stop the water flow then clean up.

And to clear the riffles I was raking my fingers through to loosen up the gravel, which I will stop doing now.

Just to be clear, when the high banker is running properly should there be no build up of material infront of the riffles? In other words by the time I get to clean up should there just be black sand and (hopefully) gold behind the riffles?

There is always some build up of material behind the riffles if they are working correctly. The lower water pressure behind them is what allows the heavier material to drop out of the flow.

Most manufacturers space the riffles too far apart for a proper vortex to be created that would allow an active state to occur behind each riffle that would keep the lighter material agitated and constantly being replaced by heavier material.

To overcome that situation and for the sluice to operate at maximum efficiency it's best if all the particles being run are close to equal size, that way gold will easily be trapped while the lighter material will wash away.

To give you an example: Lets say most all the gold in the material is pin head size and the gravels are 1/2" diameter, they would typically weigh 30 times more than a pin head of gold. Now to keep the riffles from loading up you must have a flow and angle that will move those rocks down the sluice. Guess what? Even though the gold is much denser than the rocks, because of the amount of flow needed to move the rocks and keep the riffles clear the gold will not have as much of a chance of dropping out of the flow or of staying put.

That is why classifying your gravels down to close to the same average size of the gold in the material before adjusting your highbanker will always favor the gold staying put due to the difference in density.

Just remember to always check your classification tailings for nuggets.

GG~

 

[Fullpan]

In addition to what GG is saying, you should compare the water volume to Astrobouncer's video. The water flowing at 1:50 mark seems about right to me.
http://www.treasurenet.com/forums/dredging-hi-banking/317267-hibanking-fine-gold-2.html#post2996982 Here's
another-check at :50 mark
http://www.treasurenet.com/forums/dredging-hi-banking/317267-hibanking-fine-gold.html

 

[Goodyguy]

Thanks again Goodyguy - that is some valuable information for a noob like me. I was processing a bucket of material then shutting down the pump and going to dig another bucket of material and noticed there was a bit of a surge everytime I turned the pump back on to process the next bucket. I will now get a few buckets ready and run them all at once then stop the water flow then clean up.

And to clear the riffles I was raking my fingers through to loosen up the gravel, which I will stop doing now.

Those could all be reasons that you did not recover as much gold high banking as you did panning.
With the info you've received you should be well on your way to recovering more gold with your high banker.

You could always let your high banker discharge into a bucket and then pan that material out to see if you are loosing any gold off the end.

Happy Prospecting,
GG~

 

[Barndawg]

Check your pump wires. If using a 12v dc pump, make sure the positive and negative wires are attached to the battery. Most bilge pumps are designed to rotate the impeller in a certain direction for the best performance. If the impeller is turning backwards it won't pump as well as it should. This makes a huge difference. Pay attention to the polarity when you hook it up.

 

[shotman]

Also are you useing any kind of filter on your pump? I wrap mine with window screen but the constantly have to be cleaned when you have that much plant matter running thru your system . Also i run a screen at the bottom to catch junk off the end of the sluice before it gets back to the pump useually about 20 mesh just dump it about every 3 or 4 scoops .

 

[Goodyguy]

I took another closer look at that model sluice and it appears the riffles are just too tall for 1200 gph
They say running the riffle tray is an option, I believe I would have to exercize that option.

GG~

 

[ethought]

Check your pump wires. If using a 12v dc pump, make sure the positive and negative wires are attached to the battery. Most bilge pumps are designed to rotate the impeller in a certain direction for the best performance. If the impeller is turning backwards it won't pump as well as it should. This makes a huge difference. Pay attention to the polarity when you hook it up.

Thanks for the suggestion. I tried reversing the wires and the pump ran even slower than before..

 

[ethought]

Also are you useing any kind of filter on your pump? I wrap mine with window screen but the constantly have to be cleaned when you have that much plant matter running thru your system . Also i run a screen at the bottom to catch junk off the end of the sluice before it gets back to the pump useually about 20 mesh just dump it about every 3 or 4 scoops .

I am not using any filter on the pump at this stage. But I think it would be a good idea to place some mesh below the end of the sluice to catch plant matter and stop it recirculating back into the pump.

 

[ethought]

I took another closer look at that model sluice and it appears the riffles are just too tall for 1200 gph
They say running the riffle tray is an option, I believe I would have to exercize that option.
GG~

I went back to the website and had a look but could not find where they say the riffle tray is an option. Where did you see that?

What I did notice on this page (High Bankers) which I had not noticed before is the smaller models do not seem to even have raised riffles at all?? The problem is on the 1200 model I have the riffle tray seems to hold everything else in place, so I dont see how I could remove it.