Started building a 6" dredge

[omnicron]

Yes at 20" and no not at 24". You'll be fine at 20".... word of caution about rebending your sluice. Expect it to break. Expect it to crack when bending it back strait. Expect to have to buy another piece of alum. So with that said...use a torch to heat the metal when flattening out your bend. This is the best way to lower the chance of all the bad things I listed. You may get lucky based on the thickness of your metal, what kind of alloy the alum is and it will bend out flat.

You might not have enough pump. I'm running two P180's that can push 300gpm maxed out. That's 600gpm where that P350s does 500gpm when bolted to a 25hp engine. Your jet is going to have to be built perfect. If one part is messed you'll end up screwed and not have enough water/pressure...and then not enough water in the sluice.

 

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[principedeleon]

on keene website their 16hp engine with a p350s pump states 550gpm and 150' of head. it would mean i would have about 70gpm less and less pressure then your setup since each 6.5hp engine with a p180 produce 310 gpm @ 180 psi ... i hope a quad jet like i made for my 4" make up for it. on my 4" it wanted to suck the skin of my bones lol thats how i knew the suction was right and i had no plug up.

 

[Reed Lukens]

I'm running two P180's that can push 300gpm maxed out. That's 600gpm where that P350s does 500gpm when bolted to a 25hp engine. Your jet is going to have to be built perfect. If one part is messed you'll end up screwed and not have enough water/pressure...and then not enough water in the sluice.

They rate the P180's low Omni, unless something is wrong with yours and you've tested the gpm on them, then figure 380gpm each maxed out.

Principedeleon the dove tails work great and I highly recommend them in the upper box. Angle iron works also, so make as many configurations as you want. For the undercurrent, the water runs slow enough that only expanded over carpet or rubber is needed. You don't need anything else in the undercurrent because the gold stops when it drops below the punch plate.
If you're worried about it breaking at 20" then shoot it down to 18" for the 6" side wall. Keene runs twin 13hp motors on the 6" and one 13hp on the 5" dredge. So don't think for a minute that you have lots of water because with one motor you are really limiting your capabilities.

 

[principedeleon]

They rate the P180's low Omni, unless something is wrong with yours and you've tested the gpm on them, then figure 380gpm each maxed out. Principedeleon the dove tails work great and I highly recommend them in the upper box. Angle iron works also, so make as many configurations as you want. For the undercurrent, the water runs slow enough that only expanded over carpet or rubber is needed. You don't need anything else in the undercurrent because the gold stops when it drops below the punch plate. If you're worried about it breaking at 20" then shoot it down to 18" for the 6" side wall. Keene runs twin 13hp motors on the 6" and one 13hp on the 5" dredge. So don't think for a minute that you have lots of water because with one motor you are really limiting your capabilities.

I dont know i made a mistake what i was taking about was these V shape welded to the expended mesh . I seen you used it on one of your dredges in the under section. But , as i looked into the dove tail i now know thats the riffles used in dalhke dredges . I plan on using angle irons up front and finish it with dove tail . Should that be enough?

 

[omnicron]

P, I guess I'll explain pumps to you. Pumps cause flow, they don't make pressure. Resistance to flow is what causes pressure. So when a pump is rated at say 300gpm, that is what is known as free flow ie: no hose just the pump. When you see feet of head pressure, that is not saying the pump makes say 161 feet of head pressure. Once again pumps don't make pressure. What that means is it can pump 161 feet up hill. That's it's max that it can pump, at that distance you have almost zero flow. These pumps are made to have a very tight impeller to housing clearance. That allows them to have more flow against resistance. There is a such a thing of what's called pump performance curve. All pumps have them. Some companies don't release that info (trade secret maybe) but this curve tells you it's max performance ie: best flow and capability to overcome resistance. Hopefully this will help you in your understanding.

 

[Reed Lukens]

I plan on using angle irons up front and finish it with dove tail . Should that be enough?

Honestly, I would put 4 dovetails on the back end and a few ¾" angle irons up front. Then you can put in some 1" angle irons but I really like the upside down & slanted J style because they really catch the flat gold that usually flows out of other boxes, they look kinda like a question mark - ?-?-? but slanted a bit and then the flat top angle riffles are great as well. I have nothing but good to say about the Keene riffle system so put in as many different styles as you can. Angle iron is old fashioned but it works & then expanded metal that they use for flooring or grating in factories works great also. You should be able to come up with some of this style pictured from the boneyard of any old factory so put in a foot if you can get it.

 

[principedeleon]

Honestly, I would put 4 dovetails on the back end and a few ¾" angle irons up front. Then you can put in some 1" angle irons but I really like the upside down & slanted J style because they really catch the flat gold that usually flows out of other boxes, they look kinda like a question mark - ?-?-? but slanted a bit and then the flat top angle riffles are great as well. I have nothing but good to say about the Keene riffle system so put in as many different styles as you can. Angle iron is old fashioned but it works & then expanded metal that they use for flooring or grating in factories works great also. You should be able to come up with some of this style pictured from the boneyard of any old factory so put in a foot if you can get it. <img src="http://www.treasurenet.com/forums/attachment.php?attachmentid=999118"/>

I wish i could find mesh like that i never seen something like that around here.. Just punchplate and the normal .5" expanded metal nothing raised just straight flat.

I was looking at dahlke website and their sluice on a 6" with a 13hp motor and a dp500 pump are running a 24" single stage sluice box. Cant i accomplish a good enough recovery with a set up like theirs or it might be worth it rebending it and going over & under?

 

[principedeleon]

P, I guess I'll explain pumps to you. Pumps cause flow, they don't make pressure. Resistance to flow is what causes pressure. So when a pump is rated at say 300gpm, that is what is known as free flow ie: no hose just the pump. When you see feet of head pressure, that is not saying the pump makes say 161 feet of head pressure. Once again pumps don't make pressure. What that means is it can pump 161 feet up hill. That's it's max that it can pump, at that distance you have almost zero flow. These pumps are made to have a very tight impeller to housing clearance. That allows them to have more flow against resistance. There is a such a thing of what's called pump performance curve. All pumps have them. Some companies don't release that info (trade secret maybe) but this curve tells you it's max performance ie: best flow and capability to overcome resistance. Hopefully this will help you in your understanding.

Yeah i kinda figured but by me knowing the psi i know if is wise to create too much resistance because if not it will result in a huge lack of gpm

A pump with higher head could pump at a higher pressure without much of a lost then those with lower pressure or head.

I did noticed how thight the impeller come to the housung on p350s pump compare to the ke201 pump i had on my 4" ; i even thought it was stuck but it spins freely.

 

[Reed Lukens]

Are you building a single stage or an over/ under°°° ¿ What is good enough? Dahlke pumps are not the same as Keene and having not seen a picture or having any idea how good your quad jet works leaves the end product up to you. An over/ under with dovetails & all kinds of riffles with twin 18hp motors is good enough for me. Will a 24" single stage box work? It's questionable with 1 motor and having no clue about how good your jet works, that is the point. Do you want to take the chance that it doesn't? I am one of the few people who after owning an extremely poorly built dredge from Dahlke, will never ever be a Dahlke fan. He makes good pumps and good air tanks but that's as far as I will go because the rest is not grade °Å°

 

[principedeleon]

Thanks reed.. Over and under it is!

 

[principedeleon]

Okay so im working on things.. I saw some 1/4" punch plate and 1/2" woven mesh for the clasifier. I like woven mesh more then punch plate but the holes are too wide. So if i go with the 1/4" punch plate then will the regular expended metal trap 1/4" material? The expended metal is thin and im doubt it would work right; this is what i keep finding. .. And i unbent the sluice box with out tearing. No heat was applied since he didnt have a torch; luckly it came out well.

 

[Reed Lukens]

Yes the ¼" pp will work fine . Really 3/16" works best but I would also use the ½" woven wire an inch above the punch plate and run it a couple feet down the box an inch higher than and over as many riffles as you can up to half of the box. Keene used to run the woven wire over their box that way and it works really well. You can see how they run the woven wire over the punchplate and riffles really well in the picture. I ran this way for years and it works great over any sluice configuration.

 

[principedeleon]

Okay so lets say i use two feet of punch plate; i then run 3 feet of woven mesh over the punch plate and then over 1 feet of riffles ? Like in a 3 stage?

Also You didnt tell me if that expended metal would trap the gold that would go through a 3/16 or 1/4 inch punch plate .. I was thinking on using the drop riffles mean while to i can order some vortex matting and some expended metal from the US. Im scare the water will wash away the bigger size material going inside the under current . But i dont know you should know more then me.

 

[principedeleon]

Okay so heres a update on things, i just got pump mounted and the gast air compressor apart from a electric motor it came attached too. Floatation is 75% finished. About to start working now on jet and flare.

 

[Reed Lukens]

Okay so lets say i use two feet of punch plate; i then run 3 feet of woven mesh over the punch plate and then over 1 feet of riffles ? Like in a 3 stage?

Also You didnt tell me if that expended metal would trap the gold that would go through a 3/16 or 1/4 inch punch plate .. I was thinking on using the drop riffles mean while to i can order some vortex matting and some expended metal from the US. Im scare the water will wash away the bigger size material going inside the under current . But i dont know you should know more then me.

Before the 3 stage they had an over under with the woven wire over both. It's a great system. The larger gold that drops down will usually just sit where it drops. It can move down the box some but it will get caught by the expanded just fine. I've never had a drop riffle in an undercurrent but it should work fine. You will see that 99% of the gold just stays where it drops through the punch plate and onto the v-mat or whatever mat that you have directly beneath it.

 

[principedeleon]

Just thinking about it its almost like it was to be the double clasification sluice from Dave.

Just the mesh wont be adjustable.

I havent really started out the sluice i will next week after i finish up with the flotation and jet and flare which i will start to work on tomorrow.

I want to make the jet oversized but i dont know any simple way of doing it.. Like the one quick clamp style but not sure if i might make it air thight; if not ill lose suction.

 

[omnicron]

You don't need to make the jet oversized if your building a tri or quad jet. They don't have the issue that jet logs do. Also you have a major design flaw just like I do. Your going to need to move your middle tower forward, shift your sluice forward also. This is going to allow room for your rear tower to support the flare and jet. Otherwise the water will catch your jet and hose and twist your sluice. It's not just a small issue but a major problem. The stronger the water flow the worst the issue. Also your going to need something from the top of your tower on each side to attach to your sluice to lock it in place once you get the pitch set. Also going to need something from the side to you sluice to hold it in place side to side. If you don't, everytime you pull your hose your sluice is going to jerk around possibly changing the angle or twisting the sluice.

 

[principedeleon]

I was thinking of using piece of angle iron under the sluice for it wont slide down as i tilt the box. As for twisting it wont have much room too since i made the inside diameter 23 inches wide so it haves verry little room .. Plus i was deciding to give around 33" to the jet and about 43" to the flare and It will be all just one piece like i did with my 4". It will hang out of the flotation about almost two feet . If i use something stiff to hold the jet and flare it wont move much.

My motor mount will be adjustable i will be able to slide the motor front and back.

 

[omnicron]

You can either take my advice or ignore it, your choice. I'm just telling you what I discovered and issues I still have. I have one inch on each side of my sluice and also didn't think it would twist but it does, up to 2" inches.

 

[principedeleon]

You can either take my advice or ignore it, your choice. I'm just telling you what I discovered and issues I still have. I have one inch on each side of my sluice and also didn't think it would twist but it does, up to 2" inches.

well if you did the modification; take a picture for you to show it to me for i can do it while is in the shop..
ill appreciate it.!