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gravity dredge.

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Post  maka Mon Aug 22, 2011 7:49 pm

Hi guys , i have been doing a little crevice sucking today, and have a question..
Its illegal to dredge !!!....SO....
With a creek with a large fall in terrain, If i was to use a syphon 1,5 inch hose and run it down the creek for the correct drop , would it be legal to syphon material up from between crevices?
I swim in the local creeks during summer, so i was thinking of putting on a mask, and snorkel and dragging a hose behind me while i float around on my bean bag..
The other end would obviously have to run thru a sluice set up on the other end, or i can put in a fitting like an "S' bend to trap the heavies.Or an inline sluice.
No motor used , just gravity in the design i have in my head..
I could even have the exhaust end out of the water and surrounded by a silt trap for environmental happiness..
It could incorporate a venturi suction nozel reduced to 15 or 20 mm inlet for better suction..
Has it been done? Is it legal?
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Post  Guest Mon Aug 22, 2011 9:16 pm

NO!

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Post  Guest Mon Aug 22, 2011 10:03 pm

I've done it using 100mm diameter ag-pipe with an 11 meter head. I didn't consider the legality of it at the time but using the rule of thumb that almost every activity requires a licence or is illegal then I'd be fairly confident in assuming it's illegal.

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Post  Rustydog Mon Aug 22, 2011 10:14 pm

little confusing this one as it states you cannot use a mechanical device , as this does not have moving parts to suck the gravel up i am unsure.
you could always make a phone call or two to find out i guess
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Post  Axeman Mon Aug 22, 2011 10:50 pm

I just had a look on Google for this and correct me if I'm wrong , but we are talking about a syphon hose with a sluice on the end aren't we? I don't see how a syphon could be cosidered mechanical or therefore illegal. I might be wrong Shocked though.
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Post  Guest Mon Aug 22, 2011 11:11 pm

in Vic its the act of using water to convey sand and gravel that is the illegal part and also that you need to get a permit to use a venturi ,which will never be given, I think the cutter/sucker in Port Philip bay a few years ago was given special permission to use its equipment because it did use a huge Venturi in its operation -

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Post  Chookfoot Tue Aug 23, 2011 12:32 pm

I like the AG drain pipe idea, the stuff with the constant 'riffles' !!
just a few metres of it...you'd just have a nozzle on the intake so it can't eat anything it can't pass then 20 or so metres of poly hose so to get enough fall for the syphon effect, , get around sucking up the gravel then clean out the pipe at the end of the day .....
BRILLIANT !!
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Post  maka Tue Aug 23, 2011 4:01 pm

I have sluice tested agg pipe, and yes it does work, but you have to regulate the flow. Anything over .5 of a gram actually bounces on the hard plastic and gets washed thru if the flow is too much.
I assumed this idea may be legal as its not mechanical. ( only in a few states)
I see this is a very old idea from 1850...
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Post  Chookfoot Tue Aug 23, 2011 5:17 pm

Yes Maka, your system is essentially just a 'river sluice' but the sluice is flexible and covered in. The idea of discharging on the bank with silt barriers would make it more environmentally acceptable than a standard river sluice too.
It would be however, limited to areas where the fall of the creek is sufficient to create sufficient flow and suction.
If I knew somewhere like that , I would try it !
Good Luck.
PS I wish I knew a spot (near your location) where there is a creek to float around in on the weekends that has auriferous gravel bed ?? Very Happy
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Post  maka Tue Aug 23, 2011 5:59 pm

I have a spot thats been a local swimming hole for the last few hundred years. Its at the base of a mountain. with awsome fall over a short distance.
About 6 metres over a length of 3 metres.
Being freezing cold mountain water its wetsuit time!!!!, as it has to reach mid to high 30's before its comfortable to swim in there.
The hole is too deep to touch bottom, where u jump from a rock about 3 or 4 metres up. even pencil diving i cant reach bottom.
My theory is to vacuum up all the rings, watches, and necklaces that have fallen off from people jumping from so high up.
If i get a little gold while i am there i will be stoked, as it looks like a giant holding point for anything heavy, providing it didnt get boiled out.
A few 50 mm lengths of pvc together should reach the bottom, wired to the inlet of my suction pipe.
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Post  nero_design Tue Aug 23, 2011 7:05 pm

I've been over this debate when discussing the use of a yabbie pump Vs venturi type suction. A yabbie pump is considered "manual" whereas the Venturi process is considered mechanical (and is considered to be "Mining").

You can only move material by hand. Hence a gravity dredge would be considered mining since it moves the material for you (via suction).

If the device only filtered material or classified the material shoveled into it, then it would be considered a "processing unit" and would therefore be acceptable under the hobby of prospecting.


Last edited by nero_design on Tue Aug 23, 2011 7:09 pm; edited 1 time in total
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Post  maka Tue Aug 23, 2011 7:08 pm

Cheers thanks Nero
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Post  Chookfoot Tue Aug 23, 2011 7:25 pm

Arh...Ha !!... BUT.
Gravity moves the gravel thru a river sluice, or even out of your pan... Very Happy
Sorry... Embarassed
I guess they would get you if they wanted.

So thats why you must cross breed fresh water lobsters and bower birds and train them to retrieve shiny things from your swimming hole. Razz
AND...
You can eat the ones that come back with nothing ! Wink
drunken drunken lol!
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Post  maka Tue Aug 23, 2011 7:36 pm

Lmao, great idea. they do it with cormorants and fish... How about a platypus and gold?
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Post  Chookfoot Tue Aug 23, 2011 7:47 pm

Platypus don't taste as good as lobbies. drunken drunken drunken


I'm so bored... someone post some nugget pics or something. ! Sleep Sleep
......PLEEEEZE....


Last edited by Chookfoot on Tue Aug 23, 2011 7:48 pm; edited 1 time in total (Reason for editing : gimme a reason !)
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Post  maka Tue Aug 23, 2011 8:24 pm

Platypus taste like a cross between koala , and echidna.
Yep boredom has set in, thats 4 sure...
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Post  Hoffs Gold Sat Dec 24, 2011 3:08 pm

Chookfoot wrote:Arh...Ha !!... BUT.
Gravity moves the gravel thru a river sluice, or even out of your pan... Very Happy
Sorry... Embarassed
I guess they would get you if they wanted.

So thats why you must cross breed fresh water lobsters and bower birds and train them to retrieve shiny things from your swimming hole. Razz
AND...
You can eat the ones that come back with nothing ! Wink
drunken drunken lol!

Yes yes this is a ghost thread I know, but I'm bringing it back baby yer!!

Sure does Chookfoot awesome point, Gravity and water movement is the basses of all gold recovery excluding Detecting, Dry Blowing, Leaching, and Flotation?
And Maka I say run with it mate cos if anyone that catches ya doing it doesn’t pat you on the back for outright ingenuity and effort, then he's a twat. Rolling Eyes
Plus I have some awesome spots for this idea cheers Hoff, cheers cheers cheers

P.S Lobsters and Bower birds! Classic lol! lol!


Cheers Hoff,

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Post  artrix Sat Dec 24, 2011 5:14 pm

JUST DO IT STUPID LAWS SHOULD BE CHALLENGED

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