Mustang...
Your first run should be to JUST cut the black sands from the blond sands.. then start cutting the black sands down...This way you'll be able to seperate the heavier magnetic sands from the good sulfide and teluride sands...Save the mags.. as often the platinum group metals and rare earths are often locked up in the mags.. have these processed professionally..... Like all clean up machines.. screen your material..and run like sized material for any cutting process...Yes I also get a collection of gold before the first screen...a sucker bottle picks up easily though...
Russau...
There are so many close tolerance angles, a straight edge won't work...You'll know it is warpped by the way it works.. not able to seperate the different sands and gold ... and there is NO repair once it is warpped...the construction technology and the extreme close tolerances of the table will no allow for any repairs to be completed with any significant amount of success...
It does take some time in the sun to warp.. I keep mine covered at all times except for use... I picked mine up new in Oregon.. and it was in the back of my pickup uncovered all the way to south central Arizona with out any warping during spring time weather and tempatuires...but during the summer months, especially in the southern latitudes.. you might have a problem with warping if a full day in the sun was allowed...as long as there is moving water on it.. it works just fine.. but without water or tarped, after a while it will warp...then you're done...
Klondike..