4" over/under dredg build

[Bill_saf]

4" over/under dredge build

Hello,

I have some question's for the guys or gals that have built or own a dredge.

some info on the mat that I will be moving sand and gravel some clay and silt, Sand is from 20 mesh down to talc, Gravel is from 3" and down, rocks from 3" and up

to stuff that i cant move by hand. I don't Know how far down bed rock is I tried to find it with a 2" combo had a hole about 10'x 4' deep and had heavy rain's come in

and fill the hole in twice. the Gold that I am finding is fine gold

1 how tall do the sides need to be?

2 for the top part of the dredge what kind of riffles mod clarkson's ,Hungarian Riffles how tall, how wide of a top

3 how much water would a tri-jet move vs. a couple-jet ( I have info on couple-jet and can build one if need to)

Thanks for your input

 

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[goldgit'r]

I will offer my advice and say buy a good used, unmodified dredge.
It is cheaper to buy used than to build in most cases although building equipment has its rewards.
There are some posts on here by Reed Lukins about building dredges if you do a search I'm sure you can find them.
Good luck!

Wes

 

[Bill_saf]

well I don't roll like that! LOL

The sluice box that I want is not a stock Box and the couple-jet by Gold divers is no longer made and the riffles will have to be custom made to fit the box so it has to be made by some one as in custom! And I can do the work and not have to Pay someone else. Don't get me wrong there are some things I don't have the equipment to make the pump, engine, hose and don't wish to. Think about this if it wasn't for the 49er's we would not know about sluice box's if some one didn't think of a fluid bed we would not have Hydraulic riffles. I have seen all of Reed's video's on you tube and sill I have some question's that I asked in my post. so the short answer is not go buy a good used dredge. Just my 2 cent's

 

[Jason in Enid]

With all fine gold, you need expanded over matting, not riffles.

 

[goldgit'r]

I offered my advice based on my experiences.
I too am a fabricator and have or have access to machinery to make about anything I want.
I spent my first three years in prospecting building equipment and testing and rebuilding said equipment and spent very little time actually processing material.
I finally came to the conclusion my time was better spent recovering gold than attempting to reinvent the mouse trap.
The way your questions were worded it made be think you have very little knowledge of how recovery equipment is built and why it is built that way, I may have been mistaken and did not mean to offend you.
Good luck with your project.

Wes

 

[Jason in Enid]

I offered my advice based on my experiences.
I too am a fabricator and have or have access to machinery to make about anything I want.
I spent my first three years in prospecting building equipment and testing and rebuilding said equipment and spent very little time actually processing material.
I finally came to the conclusion my time was better spent recovering gold than attempting to reinvent the mouse trap.
The way your questions were worded it made be think you have very little knowledge of how recovery equipment is built and why it is built that way, I may have been mistaken and did not mean to offend you.
Good luck with your project.

Wes

I think you are exactly correct. Lots of ideas, but no real-world experience which is why he is asking for advice.

There is nothing wrong with building your own, but you have to remember that the people who invented these things did so with tons of experience and lots of wasted time and energy before they got them right. You are better off buying a factory dredge and playing with modifications to it. don't re-invent the wheel, find a way to make it lighter, faster, stronger!

 

[Bill_saf]

Wes,

you didn't offend me in anyway some if not most times on boards like this the written word is taken the wrong way you cant hear the spoken word or the tone of ones voice. I sorry if I came across as being Brassy.

Jason,

your right on one thing lots of info in my head right now and need to sort through it. I do under stand how and way the dredge works I have spent many hours reading clarkson's riffle study, and the study's before him the one thing is they for sluice box's for wash plant's like shacker's, trommle's they do not address suction dredge's witch is a different animal. or is it?

Bill

 

[Reed Lukens]

1 how tall do the sides need to be? = Tapered from 9" down to 6" at the out flow

2 for the top part of the dredge what kind of riffles mod clarkson's ,Hungarian Riffles how tall, how wide of a top 16" to 18" wide box depending on gpm then you need to use different angles and widths on the riffles.
http://www.treasurenet.com/forums/d...1-how-build-over-under-dredge-conversion.html

3 how much water would a tri-jet move vs. a couple-jet ( I have info on couple-jet and can build one if need to) depending on the pump even a single jet log will work fine.

Thanks for your input

Or make your upper riffles like we did on the 6" in the video.

 

[Bill_saf]

Thank you, Thank you, Thank you, Reed that info is just what I needed

Bill

 

[russau]

yep you can count on Reed for a correct answer. hes got the knowledge / experience to give the answer! Theres a lot of very knowledgeable people here that also qualify the same way!

 

[Sticks]

Just about everything that I build weighs twice as much and works half as well as something someone else has perfected. Typically costs the same as factory by the time I get it dialed in, not to mention lost time and trouble packing it in and testing it. Gas is down now but it's not free yet. I guess that the real difference would be do you have a good guide to go off of? Case in point Good Guy is a member here and has a great thread on building a rock crusher. If you follow his instructions you can build your self a fine crusher at a great price. With out those directions and just an idea in your head it would surely wind up costing more and be full of bugs. I mean no offence at all, but my back yard is littered with machines that I built that will probably never work. Time for me to make a scrap run. Yet at the same time I will follow this thread intently hoping that you get it figured out for us. I would love to add an over under sluice to my circuit, and that is not a normal thing you see for sale any where. Best of luck to you Sir.

 

[Bill_saf]

Sticks,

no offense taken I have a thick hide and a head to match. lOl This is not a over night thought I have read every study from ( Peterson-1986 )
(Mcdonald), (poling), Clarkson1989-1990 the one thing that they all have in common is that the sluice box study's where on wash plants, (shaker's and Trommle's) not dredge's. Yes they all us water and screens, expanded metal to classify sand and gravel in a dredge it has to do all of the classfying in the box with a large amount of water and flow to float larger stone/rock through the box. that is where a dredge sluice box and a regular sluice box differs we all know what angles high bankers, river sluice box's need to run and the guy's that run dredge's know the angles for a dredge. I'm not trying to reinvent the wheel the box that I want it not a stock box in size (Proline, Keen) or others don make as stock off the shelf so here comes custom fab well I can build it myslef and save the custom price is it going to cost money YES but I have what I want and not add to the box. will I have to do some mods to fine tune the box to run the material that is here most likly. and if I us it some where else Ill have play with it again. Bottom line the box will not run the same way on the west coast as it will run here just because of the material will be different. as far as hauling it far I don't see it happening right now it will only be going about 100 yards to the water and go to work.

sorry for the long wind to next time Bill

 

[Sticks]

not sure if this helps you or not, but the best fine recovery I ever got was on a simple beach box that I built from plywood and ran deep v ribbed rubber. 24" wide 5' long. I always wondered if that would be a good thing to run in the bottom of an over under sluice. I read one of those studies that you cited years ago and recommended a slick plate then low profile riffles then high profile riffles all three in 8' sections if I remember right. Echelson study I think? It was the best thing they found for the fine beach gold and platinum on the Oregon Coast. If I remember it right the most important part was that there was no drop between sections. Meaning the slick plate was at the same height as the top of the low profile riffles (expanded metal) and the low pro riffles were at the same height as the high profile riffles (hungarian) The gold was allowed to travel along the same plane through the system only dropping out when it encountered deeper water (low pressure). The whole system had a drop of 1" per 1-2' adjustable. If you could cut out your fines through a -20 screen at the top of your coarse box and feed that to the lower box I think that you would be pretty happy. Water flow would be the main problem and with an over under you can't see what all is going on. However the coarse box(upper) would not need to be as wide as the lower one. I would want to be able to adjust the pitch of both independently. I don't know if you'd get the same results by shortening this down to fit a dredge. It seems the slick plate is crucial. Maybe 2' sections of riffles behind a 4' slick plate. Best......

 

[Sticks]

Before you let anyone tell you slick plates don't catch gold, remember the study. The slick plate was essential in allowing the gold to travel along the bottom while the black sands rode higher. You all have seen this feeding a simple river sluice.

 

[Reed Lukens]

Before you let anyone tell you slick plates don't catch gold, remember the study. The slick plate was essential in allowing the gold to travel along the bottom while the black sands rode higher. You all have seen this feeding a simple river sluice.

This is very true, the good old DFS sluice was a good example of the use of a slick plate along with the Bazooka Gold Trap sluices. In the over/ under dredge box the jet flare acts as the slick plate so the gold separates and slows in the flare while it's widening out and drops out directly into the undercurrent box. The Heckler study goes into the use of a slick plate and covers it really well.
http://www.hecklerfabrication.com/files/sluice-build-partIII-2.pdf

 

[Sticks]

This is excellent, that Heckler study is so full of great information a must read for any one in this industry. Great post Reed Lukens.

 

[Sticks]

Gold Trommel Wash plants & Commercial sized Highbankers Heckler Fab click on the highbanker page then click on brochure and pricing options in there you will see a stage four sluice that is an over under that will probably do what your looking for. They also do custom work and additionally have all the parts to build your own. Hope this helps you out. Link is highlighted at the beginning of this post. If link fails search hecklerfabrication.com

 

[Bill_saf]

Thanks sticks and reed I have their web page in my book mark's and I forgot to say I have there study uploaded about 2 month's ago.
Here is a pic of what I got this year its nothing to write home about but it dos show that I do have it here and the size of it and I did it with a home built 10" combo and a 2" pvc nozzle. That's a 1oz bottle

 

[Sticks]

Nice gold Bill! I really like the fines. Just about anyone can catch pickers but fines are a bit harder, good job and nicely done photo. Kudos to you on doing it with homemade equipment too. Quite industrious of you. Hope your bottom turns yellow.

 

[Gelmac]

Those are pretty nice pickers and also fines !