Grav dredge would this work?

NuggetN8 · Feb 25, 2013

Sorry for all the gravity dredging posts.. But I thought of something else.. I've got a hole that I need to suck out but there's not quite enough drop below it to make it work good but above it there's some decent drop. So if you had one of those metal dredge intakes and attached it to the hose had 50ft of hose going downstream and just as much going upstream then had that feeding the intake instead of a pump like a gas dredge would.. Would that work to give it better suction?? I really want to dredge out this hole it's driving me crazy!

NuggetN8 · Feb 25, 2013

Or even just have 50ft above with 5ft of drop going into the dredge nossle to power the suction instead of a pump and have a shorter hose on the other end going to the sluicebox?

NeoTokyo · Feb 25, 2013

I have no clue off the top of my head if it will 100% to the amount of suction that you need, it will work but will it be enough?

It would also have to be a custom jet tube because your Jet Intake needs to be the size of the tubing going above stream and then the suction and discharge sides need to be largers than the Jet Intake.

It might be better to add 100' more on your current 50'.

NuggetN8 · Feb 26, 2013

NeoTokyo said:
I have no clue off the top of my head if it will 100% to the amount of suction that you need, it will work but will it be enough?

It would also have to be a custom jet tube because your Jet Intake needs to be the size of the tubing going above stream and then the suction and discharge sides need to be largers than the Jet Intake.

It might be better to add 100' more on your current 50'.

Could I just reduce the hose I have down to the size I need for the jet tube? Wouldn't that give it more water pressure?

NeoTokyo · Feb 26, 2013

There are a few things that I am no good at figuring that play a part in this, GPM/Tube size @ set pressure, pressure/head and velocity.

I dont think just reducing it would be enough in a small gravity fed system as opposed to a pump driven system.

Pressure will rise some but it is under restrictions of head pressure, go higher and you will get more and thus more pressure as it forces more volume/gpm through the reducer.

Seems like something worth trying at the very least.

NuggetN8 · Feb 26, 2013

NeoTokyo said:
There are a few things that I am no good at figuring that play a part in this, GPM/Tube size @ set pressure, pressure/head and velocity.

I dont think just reducing it would be enough in a small gravity fed system as opposed to a pump driven system.

Pressure will rise some but it is under restrictions of head pressure, go higher and you will get more and thus more pressure as it forces more volume/gpm through the reducer.

Seems like something worth trying at the very least.

Yeah I might try it out some time.. Just a costly experiment if it doesn't work though.. I'd better choose what I'm going to use wisely so if it doesn't work that great I could still use the hose. I'll probably get some 2 inch hose to try with a jet tube.

Doitlaynstyle · Feb 27, 2013

Painters use air passed at a higher volume passed a smaller hose to create suction and you may be able to do the same. Its a draft style suction. see the pic. Please dont tease lol I drew it by hand but you should get the point. using a larger hose from way upstream should create enough flow to create suction at the tee. the suction tube should end about mid-stream in the main flow.

Doitlaynstyle · Feb 27, 2013

oh and a size reduction of 4:1 should work as in a 4 inch hose flowing passed a 1 inch intake should create enough suction to dredge.

Gold Maven · Feb 27, 2013

I don't think 5' drop would be enough. You are on the right track, but I believe you would need a lot more fall.

The old timers used gravity flow to hydraulic entire hill sides, but they used miles of pipe, and I think they reduced the diameter to increase the pressure.

Chances are if you go to all the expense and trouble to get around the motor rule, they will find another way to shut you down. Good Luck.

Doitlaynstyle · Feb 27, 2013

Sure. The reason behind gas pumps is using petroleum based products and the possibility of spillage? I am just guessing. That would probably make too much sense for democratic Kalifornians tho right? they are probably worried about changing the way the environment looks right? Its always about looks in Kalifornia. Is it all motors that are banned? Electric included? One could pay more and do a solar setup with an electric pump.... Batteries might introduce lead into an environment right? I am ranting. Sorry. Some of the Kalifornians that moved to Boise to escape their insane laws are now trying to place limits on mining here in Idaho too. I don't think they understand what winter and spring runoff does to a stream bed. Any sign of dredging is WIPED away every spring lol.

NuggetN8 · Feb 27, 2013

Doitlaynstyle said:
Sure. The reason behind gas pumps is using petroleum based products and the possibility of spillage? I am just guessing. That would probably make too much sense for democratic Kalifornians tho right? they are probably worried about changing the way the environment looks right? Its always about looks in Kalifornia. Is it all motors that are banned? Electric included? One could pay more and do a solar setup with an electric pump.... Batteries might introduce lead into an environment right? I am ranting. Sorry. Some of the Kalifornians that moved to Boise to escape their insane laws are now trying to place limits on mining here in Idaho too. I don't think they understand what winter and spring runoff does to a stream bed. Any sign of dredging is WIPED away every spring lol.

Anything mechanized is banned. So if you had somebody pedaling a bicycle to power a pump it would be illegal. The only thing you're allowed to use is gravity. They'll probably have some scientist say that gravity is under that category just to ban it.. They have a lot of excuses for the ban.. They think that we're stirring up mercury, poisoning fish and frogs, and who knows what else.. I don't really care to know what they think..

Doitlaynstyle · Feb 27, 2013

N8Longly said:
I don't really care to know what they think..

You have to sometimes so you can fight back and show them the error of their ways. I sure hope you can get this figured out. It might take a LONG LONG LONG hose but I think you could do this. Good LUCK!

NuggetN8 · Feb 27, 2013

Doitlaynstyle said:
You have to sometimes so you can fight back and show them the error of their ways. I sure hope you can get this figured out. It might take a LONG LONG LONG hose but I think you could do this. Good LUCK!

Yeah I guess you're right. If they banned gravity dredging I'd probably do it anyways though. xD ill try to figure it out but that dredge hose is expensive.

strickman · Feb 27, 2013

doubt it would work with a Y or venturi.

TerryC · Feb 27, 2013

N8Longly said:
Anything mechanized is banned. So if you had somebody pedaling a bicycle to power a pump it would be illegal. The only thing you're allowed to use is gravity. They'll probably have some scientist say that gravity is under that category just to ban it.. They have a lot of excuses for the ban.. They think that we're stirring up mercury, poisoning fish and frogs, and who knows what else.. I don't really care to know what they think..

N8. recheck the state law. I (believe) it clearly states MOTORIZED units. A bicycle is not a motor. EDIT: The current moratorium originally established by SB 670 and extended by AB 120 and SB 1018 does not prohibit or restrict non-motorized recreational mining activities, including panning for gold. It also does not prohibit or restrict some other forms of mining, including, for example, practices known as high banking, power sluicing, sniping or using a gravity dredge, so long as gravel and earthern materials are not vacuumed with a motorized system from the river or stream. TTC

NuggetN8 · Feb 27, 2013

TerryC said:
N8. recheck the state law. I (believe) it clearly states MOTORIZED units. A bicycle is not a motor. EDIT: The current moratorium originally established by SB 670 and extended by AB 120 and SB 1018 does not prohibit or restrict non-motorized recreational mining activities, including panning for gold. It also does not prohibit or restrict some other forms of mining, including, for example, practices known as high banking, power sluicing, sniping or using a gravity dredge, so long as gravel and earthern materials are not vacuumed with a motorized system from the river or stream. TTC

Thanks for adding that terry. Good to know.

Doitlaynstyle · Feb 27, 2013

N8Longly said:
Thanks for adding that terry. Good to know.

Very cool. Sounds like you could just dig that hole out and run it through a highbanker !!!!!!

NuggetN8 · Feb 27, 2013

Doitlaynstyle said:
Very cool. Sounds like you could just dig that hole out and run it through a highbanker !!!!!!

I'm going to have to stick with my sluice to clear it out. Don't have a high banker.. Maybe some day..

Grav dredge would this work?

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Dredging in North Carolina

One step forward....

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