4" dredge ready to roll

[panningjack]

Just completed my 4" dredge build. I trade my homemade high banker for this dredge. It is a old gold diver's built 4 inch. I had to buy new inner tubes, hoses, and matting. Check out the photos. I would love some suggestions and/or comments on what I could do to improve it or if anyone has any knowledge of or experience with gold diver's dredges. Thanks

 

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[HoneyPot]

Your set up looks pretty good, get some miners Moss and put it on top of your ruff top black Matt. You could even get two layers of miners moss and then have your black Matt on the bottom.

 

[russau]

well you have some nice components there. your venturi,vortex matting. dont use any miners moss on your dredge!!!! ive found out that it locks up and wont come unlocked when you slow down or stop your engine!secondly id seriously add some side flotation to keep it stable in rougher water. that will keep your material going down a parallel sluice from side to side. i took all of my miners moss out when i noticed the material locking up on me and NOT unlocking when i restart my 4 inch O/U dredge. i use Veranda carpet now on both levels of my dredge and i "might" have some vortex matting comeing to do a comparison between my Veranda carpet VRS. vortex mat.

 

[rebel003]

the dredge looks good, you will be happy with the vortex matting. I just not sure you will have enough pressure to create the needed suction from your pump to run a 4".
good luck.

 

[Fullpan]

Does anyone besides me see a problem with the 90 degree pressure hose connection?

 

[spillercanyon]

Yep, that 90 degree on the pressure hose flat out won't work and there needs to be a hole at the top end of the crash box for a rod to be used to knock out clogs in the jet tube.

 

[HoneyPot]

If your miners moss is "locked up" which I can only guess is packed full of material. Your pitch is to flat. If you don't have some kind of miners moss in your dredge you are making a huge error. You will have to play with your pitch to get it right. A lot of it will depend on the material your running. And the horse power you have on your pump and the gpm that it can provide. I agree with the floatation department the more stable your platform the better. As far a moss goes I might try that new Hog Moss. I like the look of it.

 

[dredgeman]

The power jet has no problems it is designed with multiple jets to run the tube. Infinity jets are expensive and work the best and last the longest. The 90 degree hookup is to the pressure chamber that runs the jets. The jet is usually adjustable inside.

The gold hog moss is just large loop open weave. Regular moss is small loop vinyl weave one and is fuzzy on one side. Large loop vinyl weave is flat on both sides.

 

[Fabrication Specialists]

Does anyone besides me see a problem with the 90 degree pressure hose connection?

Yes sir the "T"fitting will be an issue. The water from the pump needs to be directed up the pipe towards the hopper to maintain velocity and create a suction on you 4" line. As it stands the water from the discharge of your pump will essentially "crash" into the back of the "T" fitting and lose velocity. Then water will also head down your suction line and some will head towards the crashbox. The way it is now you won't have great suction if any and your sluice box won't have water flow to properly work. With that pump you need the water to flow the easiest way possible with the least resistance as that pump will be straining to push a 4" nozzle. The best bet would be a traditional dredge nozzle with the shortest hose possible for that pump as it would allow the pump to work the easiest with the most pressure. I would say run 2" off your pump and reduce it down to 1 1/2" for the nozzle as that would build a little more pressure. You need to keep the hose as short as possible also as friction loss in your hoses adds up relatively quick and will also eat psi (I'll attach a friction loss calculator below from my firefighting days when I was an engineer so you can see how much psi loss you have in different hose sizes). I want to say if you're running an 1 1/2" hose with a 150 gpm pump and 20 feet of hose you're losing 10 psi or so. That doesn't sound like much but if you only have 40 psi to start with you just lost 25% of your pressure before it even hits the nozzle. Those Chinese pumps are a volume pump (more water volume, less pressure) and not a pressure pump (more pressure, less volume). A pressure pump is what's really required to work properly on a dredge set up for the best suction.

Here is the link for the friction loss calculator. Nobody really thinks about this stuff (only reason I do is because I was in the fire service) but on lower pressure pumps it makes a big difference.

Fire Hose Friction Loss Calculator

Just some food for thought if you want the best possible dredge. As I've said before the pump IS the most important part of a successful dredge, this is one area where a little more money spent pays for itself over and over with the best possible operation and a minimum of issues.

Thanks, Chris

 

[dredgeman]

Yes sir the "T"fitting will be an issue. The water from the pump needs to be directed up the pipe towards the hopper to maintain velocity and create a suction on you 4" line. As it stands the water from the discharge of your pump will essentially "crash" into the back of the "T" fitting and lose velocity. Then water will also head down your suction line and some will head towards the crashbox. The way it is now you won't have great suction if any and your sluice box won't have water flow to properly work. With that pump you need the water to flow the easiest way possible with the least resistance as that pump will be straining to push a 4" nozzle. The best bet would be a traditional dredge nozzle with the shortest hose possible for that pump as it would allow the pump to work the easiest with the most pressure. I would say run 2" off your pump and reduce it down to 1 1/2" for the nozzle as that would build a little more pressure. You need to keep the hose as short as possible also as friction loss in your hoses adds up relatively quick and will also eat psi (I'll attach a friction loss calculator below from my firefighting days when I was an engineer so you can see how much psi loss you have in different hose sizes). I want to say if you're running an 1 1/2" hose with a 150 gpm pump and 20 feet of hose you're losing 10 psi or so. That doesn't sound like much but if you only have 40 psi to start with you just lost 25% of your pressure before it even hits the nozzle. Those Chinese pumps are a volume pump (more water volume, less pressure) and not a pressure pump (more pressure, less volume). A pressure pump is what's really required to work properly on a dredge set up for the best suction.

Here is the link for the friction loss calculator. Nobody really thinks about this stuff (only reason I do is because I was in the fire service) but on lower pressure pumps it makes a big difference.

Fire Hose Friction Loss Calculator

Just some food for thought if you want the best possible dredge. As I've said before the pump IS the most important part of a successful dredge, this is one area where a little more money spent pays for itself over and over with the best possible operation and a minimum of issues.

Thanks, Chris

Really With all the knowledge you hand out and you have never seen an infinity jet.

 

[dredgeman]

Agree pump is iffy

 

[bill-costa rica]

kinda hoping hoser john would jump in with some old photos i think would give you more ideas. the way it is set up it will be a little tippy. i looked for the photos and couldn't find them. you have a good dredge !! just needs a little floatation help.

bill/cr

 

[dredgeman]

kinda hoping hoser john would jump in with some old photos i think would give you more ideas. the way it is set up it will be a little tippy. i looked for the photos and couldn't find them. you have a good dredge !! just needs a little floatation help.

bill/cr

What bill said. Wheres Oates at he has all the neatest pics

 

[Fabrication Specialists]

Really With all the knowledge you hand out and you have never seen an infinity jet.

I have seen only 1 in my time (I'm a desert prospector, been dredging a few times, but have a fair amount of knowledge when it comes to pumps, engines, psi and flow rates) and the 1 I saw kept leaking from the seam in the middle and was a royal pain for the owner as water was squirting out of the top of it. Now I realize this is a maintenance issue, but I like to keep systems simple, the less things that can leak or fail the better. A dredge nozzle has no moving parts, no seals (other than hose gaskets) and is fairly indestructible unless the operator has messed up big time or backed over it or something of that sort. It's been my experience that everything works great until you hike or drag you equipment out to the middle of nowhere and then all of a sudden something is leaking, broke, won't start, etc. Personally I just like to keep things easy to work on, no funny parts or oddball items. Say you're in Alaska somewhere and your infinity jet suddenly start leaking from the middle seam. You can't run to the local hardware store and get a gasket and you may end up having to making a gasket for it (if you can find gasket material). That is a far fetched situation I know but you get the idea. Those things takes time and can be annoying to the casual prospector who has limited time to prospect as is and doesn't want to waste a day heading to town and trying to find parts. I've found over the years that simpler is better when it comes to some things and one less part is one less thing to fail at the most inopportune time.

As far as the "all my knowledge I hand out" statement, I just try to help people out and get them headed in the right direction with the least resistance and issues. I'm sorry my knowledge of infinity jets isn't nearly as great as yours clearly is, but I truly just want to help people enjoy this hobby and try my absolute best to give high quality advice.

Chris

 

[Fullpan]

I stand corrected - just got back from a link to the infinity jet. Seems it is some folks version of superior technology, and I was ignorant of its existance. Sorry!

 

[panningjack]

Great debating going on here. The Venturi is an infinity jet made by gold divers from Hawthorne, CA. The water is pumped into the body and exits 360 degrees via a gap between two pipes with one having a 12-15 degree bevel to direct the pressure. The size of that gap can be increased/decreased using a piece of all thread and nuts that you see welded to the bottom pipe thereby allowing you to tune the pressure. I am hoping that because of this adjustment my pump will work. I'm going down to the river for a test run this weekend. I do think I will be using some moss. I had a section of miners moss in my Keene mini 4" last summer and never had any problems with it. I ran in areas with tons of black sand and some with hardly any. I do like the looks of that hog moss. I might just go with that. As far as floatation, I plan on running in a small creek the first couple of months this year, so I don't think it will be needed. Plus I love the ultra portability of the inner tubes. However, I hadn't thought much of it being tipsy when I go to the big river later in the summer/fall. Good call. I do want to have 2 frames, one for portability and one for fast/big rivers. I've thought about doing 15 gallon jugs, but I want to keep the drag as low as I can, as I will be dealing with some pretty fast current.
Any ideas on pontoons? Even crazy ideas are welcome.
Any thoughts on the double classification system? It is 3/16 punch over 1/8 with a gap between the two tapering from nothing under the crash box to 1" at the end. Then the same gap between the 1/8 punch and the vortex mat.

I added a picture of the whole thing broken down. To show how portable it is

Thanks everyone for the input

 

[Hoser John]

Gold Divers was manufactured in Moundhouse Nevada east a carson city by great ol' Alfonso. Comple 360 degree jet negates the 90 degree feed in and never could get him to change it,BUT still one of the top 2 of all time for creation of suction. That units over 25 years old so construction is proof. Trouble with pics files after upgrade and still working on fix when not mining. I'll bet that antique will outsuck ANY JET MADE BY ANYONE TODAY. Our PESCO test was the proverbial slick bowling ball pickup test,same pump engine just different jets...ez to do as we tied quite a few times with our tri-jet pressure chambered iduction system,but today nobody-John

 

[Hoser John]

Gold divers was located in Moundhouse east a carson city nevada. Great ol'Alonso the jet genie came up with that 360 degree induction sysyem back in the late 60s. It will,even being 25+ years old,outsuck ANYTHInG PRODUCED BY ANYBODY NOW. That feedin hurt a bit but still passed my bowling ball suction test-HARDEST object on the planet to suck up and hold. Pics are not happening as new update screwed up my pic posting,working on a fix,but mining is first on my agenda. Only jet that ever even tied it was my PESCO pressure chamber fed tri jet and what a pain to construct,and that gdjet was a mother too. John

 

[spillercanyon]

Gold divers was located in Moundhouse east a carson city nevada. Great ol'Alonso the jet genie came up with that 360 degree induction sysyem back in the late 60s. It will,even being 25+ years old,outsuck ANYTHInG PRODUCED BY ANYBODY NOW. That feedin hurt a bit but still passed my bowling ball suction test-HARDEST object on the planet to suck up and hold. Pics are not happening as new update screwed up my pic posting,working on a fix,but mining is first on my agenda. Only jet that ever even tied it was my PESCO pressure chamber fed tri jet and what a pain to construct,and that gdjet was a mother too. John

Driving home last night, I wondered if I had spoke to soon because that coupling did not look normal. Thanks Hoser, learned something new today. You are a wealth of knowledge!

 

[Hoser John]

Jus' keep fingers away from that nozzle as she bites!!!John