Dorsey’s attempt to explain the Wave Table

I had the privilege of using the Action Mining Wave Table this summer at the mine. This is a highly effective but extremely touchy tool! Its effectiveness can not be matched when all the variables are right but this can be quite problematic in the Alaskan outback. It would work better in a lab environment.

Here is how it works… The table is a tray that has a precisely engineered weights and springs to create a bump back and forth that creates small waves on the table. These waves as they pass over the ore (sand) actually fluff the material and separate the heavies (black sand or magnetite and gold flake) in a principle called the standing wave. The gold sinks to the bottom of the table and actually walks up the opposite way of the slurry flow (water and tailing material) by a process called skin effect. The ore must be first classified by size to be effective and the better job of classification (separating by particle size) By the way all of gravity separated systems work best when you classify by size and is the first thing you do when even panning.

From what I can recall writing this blog there are several factors that you must consider when running a wave table.
1. Size of ore (not less than 1/20th of an inch) so THAT IS WHY THE NUGGET WENT in the RERUN tailing pile that Jack called the ground! It was screened by my own hands and actually never was on the table. Also, I cannot recall ever seeing a flake that size while I worked at porcupine! This could have been a “pick up” which I will talk about in a later blog!
2. Amount of ore, you must feed the table at a constant rate or risk of “packing” this is when the sand is not in “suspension” which is where the ore is fluffed in the water. To check this you just put your finger down in it. You can feel packing.
3. The ratio of ore to water or slurry ratio.
4. Angle of table
5. Bump rate (bpm for all you DJ’s out there)
6. Bump velocity (this might be wrong but I don’t know how to word it, you add weight which makes it bump harder
7. Water quality, Alaska has a high amount of organics which is I guess not good. It is best to have clean water.
8. Ratio of black sands to gold. Constantly pulling out the magnetics is important to prevent packing and keep the table from flushing all the floatable gold because of steep table angle(yes I have seen the small stuff float to the surface)
9. There is probably three more variables I am missing. You need a vacuum cleaner that will suck the gold off of the table but lets not even get into that…

I read the manual about 15 times to internalize the information, watched the dvd five times and had a lesson at John Schnables by the inventor Mike. He even showed up at our claim which no one would give him five minutes to teach them how to run the table but me.

Why didn’t ours work for us? First we needed a auger to lay down the material consistently and we did not have a constant feed of water with the correct volume. We really needed 20 gpm in my opinion and it was recycled poorly which had pipe clogging clay in it. Also we had issues with the bolts that were cemented in the ground. They were a new design which just didn’t give the table a solid footing. The table must be dead weighted S-O-L-I-D! If you have any sway or movement in the foundation of the table the waves do not work correctly. I suggest some type of square tubing straight into concrete or something. I never had a chance to solve this one without someone screwing with it. The guys in the video above I think will have the same problem by bolting the table to wood like they did. That just isn’t going to work with anything but a hand fed small amount of gold bearing material.

A word about the Hoffman’s. They did not read the manual or really have any idea behind WHY the machine works. You must understand principles of why it works to understand how to manipulate the variables to get even satisfactory results. Nothing works perfectly in Gold Mining unless you have millions to spend on equipment but for $7000 I am going to use one on my next gold mine this summer. I am just going to have the auger this time!

View the original article here