I used to own an equivalent RP4 table. The big problem is running only minor amounts of gold and you do not get a clean con.
It is after all a displacement table. The gold displaces the black sand and when you have little gold you mainly end up with mostly black sand.
It was far more effective for ultra fine gold than the cube. In addition a lot of the fine gold ends up in the middlings.
This is why I sold my RP4 table and now only use wave tables which are far more effective for ultra fine gold.
Here is a discussion by GollyMcscience about the RP4 and fine gold.
" lot depends on the nature of the gold. A shaker table works well for continuous feed of relatively high volumes. Since most riffle designs rely on heavies filling the riffles and displacing the lighter stuff it is important that you have enough gold in the material to displace the rest of the heavies or your final con will not be as clean. Generally the way to deal with that is to run the first time and reserve the high grade. The middling is set aside and added to the next run to be upgraded. Each con is collected until the con volume can justify a run on the table and then you rerun the con all by itself with the hope/expectation that there is enough gold to get the displacement system perking. The mids from this run are added back to the mids barrel to be added to the next bulk run and around and around you go. You might still have to run your final high grade on a miller to get the last black sand out.
I find a well run shaker table can handle down to 180 mesh from a minus 30 split. If running meaningful amounts of minus 150 though its better to do a minus 30 to 80 or 100 and then a minus split run by intself just because the water and table motion are harder to fine tune if that wide a range of gold is on the table constantly.
The wave table produces a line of gold that needs to be sucked off the table but it has the advantage that it does not require gold to displace the other minerals. What gold there is will work its way to the top line and stay there. There will still be a middling line so quite often I will suck just the cleanest part of the line leaving the less concentrated section to just perk away as I add more material letting the gold line build up once again. If dealing with a lot of gold in the minus 150 range the wave table makes a good clean con if you are patient enough to wait for it to form a good line.
The regular shaker table has a real hard time running samples of only a couple of 5 gallon pails because the system has to get established and it is constant clearing stuff off the table to let new stuff on. The wave table can run smaller samples because the material is held in suspension on the table with only the lightest stuff actually moving down and off while the retained bed just keeps sorting whatever material it is holding in the wave bed at the upper end of the table. Thus a relatively small sample can be run because the sample might barely fill the retained bed but if you wait the gold will work its way out to the line at the very top edge."
George
George, you and others, make some really good points. I did level the table after I bolted it to the concrete floor.The sand is in buckets and is suspended from the lower portion of the table, not in bags. I plan to double check the table, maybe start over on the leveling, just to be sure.
As you noted, the fines are small and not frequent or rich enough to run a solid line. As a result I can see much small fines running under the black sand.The larger ones do run high into the #1 port. So then much is in the # 2 port. This is really frustrating as I then have to re-run # 2 etc. to get it down to anything close to real concentrates. I also took some concentrated material from a previous operation and ran it thru, it did a better job of holding the gold in line for the # 1 port.Due, I guess, to the amount of gold, as you and others have noted it would.
I wish I had a wave table to compare the one table to the other.
At this time I think I'll run my raw material thru my sluice set-up and then thru the RP-4. It is too much volume to run all thru the table first.My sluice is an A-52,the header or slick plate has shallow matting, the lower portion is lined with green felt, then Gold Hog matting, this then dumps into a shorter sluice, which has the lining and regular V matting, but is set with less slope.I clean it out frequently. I don't know how this would compare to a Gold Cube.The guys I know who run material at the beach had a Gold Cube, they sold it and went to Gold Hog matting in combined sluices.They say they get better retention.
I do know that much of this material is what would be known as micron gold, as it will easily drop thru a - 90 screen.It looks like orange sand when concentrated.But, there is lot of, of course it takes a lot to make up any volume. Every now and then I will find some flakes that won't go thru a 20 mesh screen.
Thanks again for all who have responded. It all helps me to better understand what is going on.
George, do you know anyone with a second hand wave table??
