H&F909ORO
If you decide to make your own, there's a couple of important things to keep in mind. The single most important of these is water flow. Think about how and where you plan on using your sluice. If you're going to go for a re-circ system, you have to make sure you have a pump that can move enough water for it. The wider you make your sluice, the larger the pump you're going to need. While a 5-1/2 inch wide "Long Tom" style running carpet for matting can get by with around 750 gallons per hour, a 12 inch wide is going to need something in the 1250-2000 GPH range to work effectively. It's always best to get the largest pump you can afford. You can always add a valve to cut back on the water if needed. If you're going to use it as a stream sluice, the same thing applies. You're not going to want a really wide sluice if the stream you plan on using it in doesn't have the flow needed for it to work right. If the water flow on either system isn't enough, your riffles will get packed up with materials and before you know it you're flat boarding your materials and loosing gold out the end. If they're packing up you will need to do one of three things. Get more water going through it, increase the drop of the box, or slow down on your feed rate.
Another thing that is going to come into play when it comes to how much water you will need is what type of matting you're using. Simple ribbed carpet will need less water flow than something like "Miners Moss" or the Gold Hog matting. Different types of matting will also have different requirements when it comes to classifying your materials. Some won't work well with larger sized materials unless you have a lot of water to move the materials through the box.
If you go for wood construction, your best bet it to use a good marine grade ply-wood. Even then you're going to need to seal it up with several heavy coats of polyurethane or marine spar varnish . Solid wood has a tendency to warp once it's been soaked and allowed to dry even if you've sealed it. Once it's warped, there's not going to be any straightening it.
Of course if you don't have access to a shop area to make this sluice, you may be better off buying one from a shop or fellow miner. I've always made my own sluices but since I just picked up a claim I'm thinking of getting something like a Gold Hog Viper Highbanker so I can move a lot more materials.
