8 inch gravity sluicing

Hi oakview. Not at all if your intake is submerged at a higher level then discharge end and your hose don,t have to go over big hills, sometimes you don,t even need a cap at discharge end,just lift the end out of water,pressure fills the hose,when filled submerge it and let pressure push out remaining air bubbles,sometimes with alittle help by kicking the hose where bubbles are
 

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oro e lavoro
been following your build on another forum, good job ! i am sure there are a lot of people who would like to see the process.

bill/cr
 

Hi bill,thankyou.i,ve been reading your posts too.i remember one post about the expanded aluminum you where using on your monster 10 inch,that you replaced with same exp.but made out of metall,correct?Well i learned much in the net and in post like yours and ouf course from the pro-kiwi dredgers ,i think i use almost the same expanded for fines like you.Glad to give infos back about gravity sluicing(thats what i ,m doing,no motors or mecanical devices allowed here).I,m still learning as i can not do it as my full time job ,it takes many weekends and holydays to get the experiences but if i can help i,m glad to do it.Saluti :emilio
 

this pic is from last year, this was 100' of 4" pvc, can't seem to find the picture of this year’s set up, which is much shorter than last year, i am running 60 feet 4" pvc with a 4' drop
suction on the head is incredible, like running a motorized dredge, Problem i am facing seems the bends and dips, will load up with material then reduce suction. so disconnect and clean out get the flow goin again, doin by yourself is tough, taken the pipe apart and putting together in the fast water would just ware ya out, it's a laugh, tripin slidin, catchin stuff tryin to go for a ride, so i guess my question is do you find the 8" load up on the bends and dips? how much drop do you have for your length of hose?
 

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Just gotta love it as been doing it for years and definately a learning curve motorless,miss the air but what's a miner to do...stop :censored: hahahaha never-John :headbang:
 

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I like it, that's badass! :)

Do you have any pictures of your cleanup?
 

your a howl John, this years set up, took awhile to find pic , don't have air this year, but ran air from the bank last year, sweet, this was last years one day take
 

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hi 2cmoreau,john and neo tokyo
I have 2pieces of 26 feet o 8inch polyurethane hose with pvc spiral,they are connectable if needed with a oversize coupling.InView attachment 1057088 In the video set up i had nearly 3 feet of drop on 26 feet of hose,but no dips other then the one when hose goes up to the flare.I had no build ups ,but this is a ideal prepared site during a one week trip.My first production trial with the 8 inch by the way.It was just a dream to work with ,even though i had only c.a.12 hours of nozzle time and a partly loss off concentrate because of a waterbomb(thats how they call it where i dredged) during clean up.Was a little shock but nobody got hurt and we found all the gear the next day downstream,but had to rebuild the dam.Also a local goldpanner denunciated us by the parkranger,but he made a fool of himself in front of all,as i had all the permitts required.Dam after waterbomb;View attachment 1057103 sluice made it thru the night,but our tub with best part of concentrate emptyed himself back to river;View attachment 1057105good thing was the tailings build up swept away too.Clean up pics after first test runs;View attachment 1057107 View attachment 1057113 View attachment 1057114 black mat first section after two hours c.a.View attachment 1057123Also the cemented gravel layers where hard to work,but good thing was there was only 3feet to the claylayer that acted as bedrock.View attachment 1057149
Generally i like to have 10%of drop related to hoselenght i use,so for your 60 feet you should have 6 feet drop,but may work also with 5 feet when no sharp bends and dips there. 1feet more drop can make the The difference between a pain in..and a good workable setup.I have also a 4 inch set up with many different hoselenght,which makes you more flexible.I will buy also a 15 feet piece of 8 inch when i recovered from expences i had lately.The less hoselenght the less drop you need,so check your site for natural drops near where you dredge ,you have to carry less hose with you.
Your creek in the pic above looks just ideal for a little dambuilt. ,Its past midnight here,write more tomorow,cheers,emilio
 

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Just go to the sewer pipe department at Lowes/Home depot and life gets easier...and much cheaper. Sucking ANY air is the killer as much prefer a solid piece of hose or junctions should be fabbed to remain underwater so any suction leaks suck water and NOT air as then slowly but surely your prime goes unprime and your left standing there holding your hose :dontknow: John
 

.... as then slowly but surely your prime goes unprime,
and your left standing there holding your hose :dontknow: John

Don't ya just hate it when that happens?
sSig_aaarggh.gif


Younger hoses shouldn't experience this problem, but for the older
ones it becomes a more serious issue.
old.gif


(John...you're such a good "straight man" that I couldn't help myself...)

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I'd love to try a gravity dredge someday, but hauling in all that
hose would be an awful lot of work if it didn't pay off well.

Do you feed the outake end right into a sluice, or do you run it
through a header box?
 

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little black dots in the picture on the white PVC, rubberhose couplings, helps keep the water flowing for us old farts
 

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I agree john,when coupling is not airtight it has to stay under water.I help the coupling with a sort of banding sleeve i made out of small soft pvc hose that fits tight in the pvc spiral of suction hose,it should be slightly higher than the hard pvc spiral of suction hose so the coupling compresses it. el2014 029.jpg That did the trick.
 

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