Building A 9'x3' Sluice Box For An Old 8" Dredge in Gold Panning, Sluicing, Dredging, Drywashing, Etc Posted October 10, 2020 On 10/9/2020 at 7:43 AM, Steve Herschbach said: Sounds like you’ve done your research. The Poling and Clarkson reports are great. Fine Gold Recovery of Selected Sluicebox Configurations 1989 Gold Losses at Klondike Placer Mines - Gold Recovery Project 1989 An Analysis of Sluicebox Riffle Performance 1990 A review of placer gold concentrate recovery and upgrade options 2011 I’m a carpet under miners moss guy due to Clarkson. Thank you Steve. Some of those I haven't read before. Great reads for sure. I've never seen actual 90 degree angle iron run in a dredge before. Its always been a modified type dredge riffle from Keene or Proline with more of a 45 at the top running flat with the box. The riffles in this old Dahlke are the same with the addition of 1 1/2 flat bar in some areas. The way this box is set up with the header going from 24" wide to 34" wide over the first 3 feet would seem to me to be the best location for un classified 1 1/2" riffles for bigger gold. Then run a 3/4 to 7/8 wire mesh screen over smaller riffles and expanded for the next 3 feet. Last 3 feet run 1/4 mesh over small expanded.