building a dredge...sluice question

[n.h.gold]

Hi all! New to all this, I have done much reading and have started building my dredge-highbanker..I have a p-180 pump powered by a Honda. The sluice I am building is 14 inches wide and 4 feet long. The sluice has 3 levels, first on the floor has converyor belt (looks like vortex mat to me) covered by raised expanded covering it with 4 riffles at the end. There is an inch and a quarter to the next level which for the first 2 feet is 1/4 inch punch plate, then a solid bottom which has conveyor belt covered with mesh then 4 riffles. An inch and a quarter above that is 3/8 inch flat expanded which ends above the 2nd level riffles...I have a crash box in the front. My question is do I want to run the screens to the head of the crash box, or make a false floor so that all the material has a floor to hit then hits the 3/8 expanded and the material classifies down thru the screens as it flows down the sluice? I plan on having an Alaskan damper over the 3/8... Also, how do I know when I have the water flow to the levels correct..I believe I will be able to regulate the flow by changing the length of the punch plate-solid floor..I live in new Hampshire where the gold is both sparse and fine. Thank you so much. Any suggestions are appricated. Parker

[russau]

thats a lot of sluice width!! 42 inchs wide total for 3 levels! if you can see the mats/riffels/etc. look to see if the material is "danceing" behind the riffels and clearing the bigger stuff and NOT building up a bunch of material.i have a over undersluice for my dredge with that eng/pump configuration and its a balanceing act for it but with 3 levels............have fun and good luck keeping them clear!

[n.h.gold]

The width is 14 inches wide and 48 inches long. I am sure I will be making a lot of modifications as I go...finding out what works. Any wisdom for the collective years of experience here is much appricated.
Thanks, parker

[russau]

yep i understood that each sluice is 14 inchs wide times 3(sluices) equals 42 inchs of sluice width. youll need a lot of water to make it work!

[n.h.gold]

Got it..that's with input I'm looking for..I'll know more when I try it ...

[Hoser John]

Convalution is not the solution. When you put expanded metal,or any such objects,that make it impossible for the riffles to seal FLAT you are just blowing gold down the box and out. Take a flashlight in the dark and shine it on the riffles,ifn' ya see light coming under ?THAT is where the gold will escape as MUST seal. A very simple over/under with a rubber difusion curtain will do what ya want without 3 layers of stuff,which when added up requires a huge amount of water to fill all those levels. Multiple level feedins would be needed .Forget that crash headerbox and any powerjet as creating a frothing mess and remixing whats been classified in the hose is the absolute worst scenario in microfines retention. Keep it simple and prosper....John

[n.h.gold]

All right..if I don't use a crash box or power jet what do I use to transition from hose to sluice? So under riffles go with miners moss? Thanks, parker

[russau]

use a suction nozzel.

[n.h.gold]

With a jet flare to transition to the sluice box? Just about have the new power jet finished. Might as well build a suction nozzle as well...the old power jet I built this winter has no reduction from the 2 one inch feed lines into the log...(did not know it was necassary)
The p-180 makes a lot more suction than the pacer pump did using this power jet..but what a bunch of bubbles (I just have the end of the jet stuck in the end of the sluice with a damper)...really overwhelms the a-52 sluice with flow...learning as I go...I was surprised to see that the little Keene was concentrating garnet and black sand even with the massive volume of water running thru it...I love hearing those rocks crash thru the sluice.

[Hoser John]

A-52 is a small sluice with shallow sides,you have NOT mentioned what size dredge your trying to make-??? As it will barely handle a 2 1/2" flow withiut overflowing the sides.. John