Happy Sluicing
Nice looking legs! ON the sluice box. I've had the stock Keene work well for fines as well as nuggets. When the Keene is in the water it becomes very heavy due to water and concentrate weights added to the sluice itself making it Ugly/Awkward to take out of the water. I added a cross bar at the top of mine that acts as a top handle making removal out of the water and back to the shore much more stable/reliable.

You can see the two bars I added at the flare area, only the lower one is needed. Note the bucket being used with the A52 insterted all the way to the bottom of the blue bucket!! The A52 jam fits in a standard 5 gallon bucket and it can break the standard 5 gallon if not used carefully. The blue bucket makes it all so much easier.
Proper setup, the water should just be breaking over the riffle bars. When the box is level from left to right the water will naturally create a "V" then an "X" pattern in the water going down the sluice. With the right amount of water and sluicebox angle the sluice can run for hours before cleaning, this is what I'm told. If the riffles clog up with sand/dirt that does not wash away then the amount of water or angle of the box are not correct. The material on the down flow side of the riffles should be dancing in the water flow, this allows the light material to float away and heavies to take the place of the light material.
A magnet is a handy prospecting aid as it will pick up attractable material, iron mineral. I keep mine in a 35mm film container w/lid on and just an up/down motion of the container is enough to let the magnetic material fall right off, this keeps the magnet clean. Again, good luck!....................63bkpkr
After assembly of the flare to the box there are likely to be some gaps at the corners of the box to flare joint, a small amount of waterproof putty/silicone keeps the fines and pickers from being lost out the gaps.