(Once more...a better mouse trap?)
There's always some room for improvement in small-scale mining gear. Come to think of it, this is true in all aspects of our lives. That said, the humble sluice box is a pretty basic design in terms of design, function, and gold-trapping ability. But is there a better mousetrap in this regard? Therein lies the heart of this series of posts.
OK, let's continue our look at the comparison factors of a standard, single water flow sluice box, the A52 manufactured by Keene Engineering.
3. Ease of Set Up
Any sluice box (barring the Long Tom or sluice box in series) is a fairly easy set up. Let me qualify that statement a bit. I have to admit it takes some fussing and fidgeting to get a sluice box set properly and operating at peak efficiency. How long you fuss and fidget with that box is based on any number of factors, including water flow and relative ease of access. The A52 is easy to set up once you've dialed in the slope and pitch of the box, and have it firmly braced in place with rocks, etc. Most sluice boxes (manufactured or do-it-yourself) will float away on you in decent water flow so bracing is a must. The A52 is no different in this regard.
(The Keene A52 high-production sluice box.)
4. Feeder Tray/Header Box
Whether they're single or double flow, this is one key factor that most manufactured boxes are remiss with. Other than the A52 and a handful of models manufactured by other concerns, many manufactured sluice boxes today DO NOT employ a feed tray or header box and that's probably why you see so many YouTube videos of small-scale miners sluicing and feeding their boxes with a garden trowel or large serving spoon. I reckon this is all fine and well if you're crevicing or running other concentrated material, but if you want to shovel directly into the box without classifying your material or you choose to move boo-coo dirt, it's an exercise in futility to a great degree. Over the years I've shoveled unclassified material (rocks included) directly into my A52's fan-shaped feeder tray and I've also poured screened material from a five-gallon bucket directly into the header with excellent results as long as I had good water flow. This is a real plus of the A52 and truth be told, I don't understand why anyone would design or manufacture a sluice without a reasonably sized header box or feeder tray.
I believe that the dimensions of the Keene A52 sluice box are pretty much perfect (51" x 10" x 4.5"). Again, even in my greenhorn daze (days!) I fundamentally understood the workable dimensions I needed to make my first do-it-yourself (DIY) box a success and the dimensions of that wooden DIY sluice were very, very close to the A52's. Blind luck, again. Anyhoo, the A52's dimensions are robust enough to allow the box to handle large amounts of gold-bearing material while still maintaining a decent level of portability. It doesn't get any better than that methinks.
6. Gold Trapping Ability
Any sluice box's ability to capture placer gold (including fine or flour gold) is directly contingent on any number of factors, not the least of which are how well the box is set up (angle and pitch), water flow, and the number of riffles and their height and spacing. Again, I've been using my old timer's version of the Keene A52 off and on for over 35 years now and its gold retention capabilities are outstanding overall (again, providing you know the difference between your ass and a hole in the ground regarding set up). The A52 employs eight riffles (or riffle cleats) over the length of the box, minus the header tray of course. Underneath the riffle tray is a short section of expanded metal screen that I believe is 16-18 gauge with 1/2 inch diagonal holes (not absolutely sure of these measurements though). Underneath the expanded metal is a strip of indoor-outdoor carpet that runs the length and width of the box. Yes, I know that miner's moss is a big favorite these days, but the A52 is sold with carpet, like it or not. Over the years when using my older A52 I've noticed that gold of any size or weight (including nuggets, coarse pieces, and even small-to-medium flakes) will remain either in the header tray or behind the first and less often, the second riffle cleats. The A52's fine gold trapping ability is very good to excellent, but on occasion I have undoubtedly lost some of the fine stuff...it's just part of the deal. Remember, any gold lost when using a portable sluice box is not necessarily the box's fault or the result of a faulty design, but is more than likely a result of something I call "operator difficulty." You newbies and greenhorns out there take note.
(It's a miner and his equipment that tell the tale when it comes to fine gold recovery.)
7. Ease of Clean Up
Clean up with the A52 is a breeze. The hinged, one-piece riffle tray is simply unsnapped from the end sides of the box and lifted up, allowing you to remove the expanded metal, roll up the indoor/outdoor carpet, and then place same in a five-gallon bucket of water. Any remaining concentrates in the bare box length can then be flushed into your carpet bucket. If you've been around the small-scale gold mining block for a while this will take you all of five minutes, if that long. (By the way, I LOVE clean ups...don't you?) To get going again, just reverse these steps and get your A52 back in the water.
Am I partial to the Keene A52 portable sluice box. Damn straight I am. It's proven itself to me over and over and over again during the course of my checkered mining career and has never let me down. As I've said already, its taken some real punishment along the way and has proven itself strong, durable, and efficient at getting the gold. In other words, the A52 is a single water flow sluice box with a proven ability to get the job done without needless thrills, frills, or chills. There it is...
Next time we'll take a look at one of those new and improved "mousetraps," the Bazooka "Fluid Bed" Sluice. Until then, keep the faith and don't take any crap from anyone.
(c) Jim Rocha (J.R.) 2015
Questions? E-mail me at firstname.lastname@example.org