Keene 3 stage sluice tuning

[Bonaro]

I have a Keene 5" dredge with the 3 stage sluice. I like it and I have been tweaking on it to improve efficientcy but I want to hear from others to see what they have been finding.
I have a lot of heavy black sands in the spot I dredge and the undersluice loads up badly. I run a steeper angle and the plate wide open but I am not satisfied. I have several other mods in mind but what have you guys done?

 

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[Bonaro]

I was thinking that, after a project like that, tuning this new 3 stage should be a walk in the park. Now I'm thinking that the amount of heavies your into would probably give any recovery system fits.

Anyway thanks again to you and the others who shared their experience on the old forum. The discussions that happened there were invaluable to a lurking newbie.

Here is a short clip showing the simple lift kit I made for the 4" dredge. Rectangular alum tubing wasn't the ideal dimensions, but priced right as local rems.



If I did this over again I would lift it 3" instead of 2" though.

I have ridden in this rodeo a while now and I have already pretty much figured out what I need to do to overcome the heavy black sand I encounter.
However, I would be foolish to believe that I know it all...which is why I asked the question here....I knew I would learn something new.

 

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[Gelmac]

Sorry, I went back to the archive on 49ermike.com and could not find the posts I made, that was almost 10 years ago...all I have now is pics.
Anyone with good fiberglass casting skills is already familiar with how to build this, all they they need is the design. It took considerable trial and error to develop this shape but it finally worked and worked well.
fyi - I have had quite a few people ask me to build one of these for their dredge. After I penciled it out I found it was FAR too time consuming to build them for hire unless I tooled up for some commercial grade molds.

Thanks Bonaro, that is Awesome ! with a raised up flap it looked like some of the sci-fi ships just jet ski with that one , and you could win the first prize !
What size of that space ship, lol, by the way? is it a four incher?
Sorry you lost the posts, may be someone that have part of the old archives of the forums, think Reed may be? I know he used to be a Moderator there , but not sure if he kept some of the content of that great forum

 

[Bejay]

I have ridden in this rodeo a while now and I have already pretty much figured out what I need to do to overcome the heavy black sand I encounter.
However, I would be foolish to believe that I know it all...which is why I asked the question here....I knew I would learn something new.

It sounds as though you have chosen to raise the system so the end does not submerge into the water. if I am understanding your intentions correctly, in order to achieve the "raise" I inverted the whole frame and turned it over.....bottom side up. That raises the whole sluice system. Then one must alter the Motor/Pump mount by adding a metal tube/box frame that bolts to the existing frame. The jet then passes underneath and through the added tube/box/frame. Pretty simple to do!

Bejay

 

[specksandflecks]

It sounds as though you have chosen to raise the system so the end does not submerge into the water. if I am understanding your intentions correctly, in order to achieve the "raise" I inverted the whole frame and turned it over.....bottom side up. That raises the whole sluice system. Then one must alter the Motor/Pump mount by adding a metal tube/box frame that bolts to the existing frame. The jet then passes underneath and through the added tube/box/frame. Pretty simple to do!

Bejay

Pics or it didn't happen! Just kidding. That sounds like a perfect solution.

Seems like I faintly remember pondering something like that but decided against it. Maybe it was my lack of a wire machine. Stick machine+my crappy welding skills= difficult to get decent welds on that size square tubing keene uses for the frame. It would have been less work than what I ended up doing and I'd get to raise my flare more!

I have been wanting to raise the engine platform on mine an inch or so just to get my flare running a bit flatter. As it sits now the top of my flare hits the bottom of the frame where the engine mounts :/

 

[Bejay]

I am not take pic guy and post to a computer....don't know how. Easiest explanation is to picture, if you will, 2 individual square " frames" (like picture frames made out of the same size tubing on your existing dredge frame). Then bolt the existing two new (tube pic frames) frames where your motor currently mounts (of course on the underneath spot sense the frame is inverted). Then mount the motor/pump to the top of the frames...then the whole unit forms what you might consider to be a open box frame. The flare jet passes thru the open box frame under the motor/pump. You can get someone to weld a set up if you don't weld yourself. I use a few good bungies to hold the pontoons to the frame sense the pin system fails to lock/secure....merely by going from one side to the other underneath the sluice.

Bejay

 

[Bonaro]

One of the other things I have learned the hard way is to simulate the modifications you want to make without cutting the frame apart. My buddy and I use to joke about having to completely cut the dredge into little pieces and weld it all back together again every year and waiting until June to start it....no more...lol
I think I will try raising the box with a 2x4 and if I need more slope I will stack rock on the tail. If that works I will cut and weld next winter

On the subject of black sand clogging the riffles - I had a lengthy conversation with Pat Keene about tuning this 3 stage sluice. His recommendation was a smaller screen for the under, more angle and increased cleanup interval. All that is pretty straight-forward.
One of my ideas I discussed with him was to weld some strips of metal to the vertical rails on the top of the lower riffle tray. This would make the cookie sheet sit higher off the bottom riffles. Relocate the upper riffles to match and that should dramatically increase the water flow to the lower. My target on this would be about 3/8". He thought this may work but was reluctant to endorse it probably because it would be easy to fubar the sluice if you fumbled this.
He also talked about magnetic removal of black sands prior to the first stage. He disclosed the development of some sort of rotary magnetic separator that fit as an attachment to the flare. I am excited to see what this is about and several conveyor belt type designs have been bouncing round in my empty head.

 

[Bejay]

I never cut the frame!

Simply turned it over and bolted on (using existing motor mount holes) two tubular bracket frames that raise the motor/pump.

Bejay