Highbanker, propmaker style. (WIP)

[AusFX]

So I'm going to start building a small highbanker, never made one before, or even used one for the matter. I understand the concept well enough, hopefully enough that it works.
I'm setting myself a little design brief/challenge::

24 total hours to build (over several days in between everything else)
I can only use material I find around the workshop (which probably means it will be mostly timber with some metal parts). This does not include the riffles, carpet/moss and the pump.

General dimensions would be approx 600x300, removable bolts so I can pack it down.

I have heaps of 17 and 19mm ply in a variety of grades and plenty of pine 2x1's, those should do nicely for the framework.

I was thinking of sealing it with a polyurethane for waterproofing, try and stop the timber warping too much.

I'm hoping a 12v pump will be enough so I can cart around a battery and don't need to find mains or spend the money on a petrol pump.

Any suggestions/comments are welcome! I'll post pictures throughout the build, should be starting on monday.

 

[Twapster]

I would be thinking your dimensions are a little out, if using a small pump you may need it to be more like 600 by 200 as you want a little better water flow. I dont think you want the box more than say 8 inches wide and maybe even taper down as a 12v pump wont be pushing out that much water.

I bought a mini 12v banker on ebay and yes it works with the 1200 bilge motor but not at any great speed. I became quickly frustrated I couldnt process more dirt, however it is much faster than panning. I built a bigger banker!

 

[AusFX]

Thanks Twapster! I'll make it 200m wide. I was thinking I would classify the material down a bit before I run it to make it a bit easier for it to process.

I'm going to bunnings today to see what I can find for the riffles and carpet. (if I use angular fiffles I'll just weld those together from mild bar since we have plenty of it around)

Something I'm curious about, I've seen sluices with carpet, expanded mesh and the angular riffles, I've also seen them with combinations of these, such as carpet and mesh, carpet and just angular riffles, etc.
Is there any particular combination thats most effective?

 

[Goldtarget]

Just my two specs worth carpet can be a real pita to clean out cons from but some people swear by it. Moss or vrib matting buddy when it comes to clean up you'll be thankful you didn't go carpet. I think it's false economy to say is a cheaper effective option. Dimensions seem OK nor sure if your going to get the slick section you need but pre classifying will bea big help.

 

[AusFX]

Thanks Goldtarget, I'll keep my eye out for some Vrib, I've noticed the moss seems to be a bit pricy (at least the stuff branded for gold).
Not reason I cant swap it out down the track anyway

 

[AusFX]

I just did a quick bunnings trip and picked these up:

Any advice on which to use would be great, if either of them.

I also saw this when I was there but didn't buy any, thought it might work?
http://www.bunnings.com.au/ideal-di...topdeck-duo-ribbed-uv-marine-carpet_p6620941#

 

[Goldtarget]

Both if that Grey Matt is unbacked otherwise some of the gold will go in and pass out straight along the bottom. Vrib under Grey mat with your riffle system or expanded mesh on top. Our you cam use the vrib on its own but holding fines will be the issue unless in really slow flow ( cons cleanup only). Have a gander around the topics if its still unclear but you now have the goods.

 

[Goldtarget]

I'll put up a cpl of pics when I get home from work if your still Un sure. Just put the finishing touches on a Banker so from that you'll see how I set it out. Might even put it in the diy.

 

[AusFX]

Excellent, I'm pretty sure I know what you mean, from bottom to top: Vrib, Grey mesh, expanded mesh or riffles.
Some pics of your setup would be greatly appreciated Goldtarget!

Back in the workshop tomorrow, should be able to bash out most of it then provided I can find all the timber I need.

 

[AusFX]

Also regarding Pumps, would one of these work okay? Anything in particular I should look for in a pump?
http://www.bunnings.com.au/commercial-electric-36w-600l-hr-pressure-pump-_p4816177
http://www.bunnings.com.au/ozito-600w-transfer-water-pump_p4816178
http://www.bunnings.com.au/ozito-350w-submersible-water-pump_p4816179

 

[Twapster]

Ill give my 2 cents worth...gold is heavy...very heavy and falls quickly. Doesnt really matter what set up you have as long as it allows the gold to be trapped. Ensure ur not loosing gold under your system and then its either gravity or water flow that does the rest. A 12v system is just like panning but quicker. I dont classify...it takes too long I chuck everything in and wash those rocks or clay...that big boulder may be holding a few nice pickers and if you classify you loose them by chucking aside. On a small banker its harder...cant handle those 10 kg boulders I like to throw in. But even a mini banker can handle a bit but yes sometimes classifying might be justified on a small sluice set up. Best to make a sluice that can handle at minimum 1 shovel of ANYTHING.

 

[Twapster]

Some pics of my gold set up with sapphire extension

Yes I have ribbed mat at the top, expanded mesh, bunnings large weave mat with backing, bread crate pattern and Milk Crate pattern for Sapphires as an extension.

All Wal inspired!

I use a rear classifier system with an extra long Wal Classifier, something about rear classifying I just prefer. The second tier also allows me a little extra water flow with a smaller pump. Hope that helps some insiration for someone.

 

[AusFX]

Thanks Twapster!

Some progress has been made!

Yesterday, constructed the main body and started the waterproofing.

Today, completed the water proofing (although I'll probably do a few more coats of shellac in areas I had to sand down the polyurethane a bit)
And welded together the riffles. I was going to buy expanded mesh but I'm trying to get this done by the weekend, plus the riffles didn't cost me a thing aside from 30 mins of my time.

Needs a bit of a clean up, a few more holes and bolts, then I can get onto the hose for the pump.

Total time thus far, about 4 hours, money spent, $20 for the Vrib and mesh, everything else scrounged from the workshop.

 

[Goldtarget]

Looking great. Watching with interest.

 

[Twapster]

Awesome build there, bound to trap the good stuff!!

 

[AusFX]

Awesome build there, bound to trap the good stuff!!

Haha, thanks, thats what I like to hear

Finishing touches and pump stuff should go on tomorrow. Can't wait to see how it runs!

 

[Goldtarget]

If I can make a small suggestion that mesh in the top box would be better on the underside of the opening at least at the top. You'll find the gravels will trap in it between the wood and the metal otherwise, probably best if both edges are on the underside. I learnt this from my trommel builds

 

[AusFX]

Thanks for the tip Goldtarget! I'll move it to the underside tomorrow.

 

[AusFX]

Did a few tests today, I tried a small 13.2LPM (3.5 GPM) electric pump we had on hand, but nowhere near enough water was going through it.
Then I tried the mains water and it was a bit better, but I still think it won't be enough to move the material and not clog up, I also had to remove the moss for water to flow over the riffles at all.
I figure I have a few options here,
-Buy a 1.5 inch petrol pump. (but that kind of defeats the purpose of this being a budget build)
-Buy a better 12v pump and hope it pumps enough water (if not, find expanding mesh that's not as big as my welded riffles)
-Take out the moss and just use the big riffles and Vrib. (will this catch gold as well?) I might still need more water anyway.

This would be a lot easier if I was testing it at Clunes, but I can't bring my tools there if it needs significant modification or a new build, and I don't have paydirt here to test it.