Riffles and sluices

[stretch]

stretch

Has any one tried drooped riffles And rubber matting?

If some has did you make your drooped riffles or buy


them? Also how deep and how wide are they? I'm

thinking of making my own and using vortex matting.Any

Ideas or suggestions I would really appreciate.

[russau]

Stretch over on www.treasurenet.com Astrobouncer has made them and posted pictures and dimensions of what worked for him.

[Sierra Sam]

What exactly is a drooped riffle?

[micropedes1]

I machined drop riffles 1/2" deep into Lexan polycarbonate. Riffle spacing at 1.5". Downstream taper at 15 degrees. Panels are 30" wide by 36" long. Just right for my 8" dredges!

I actually machined individual riffles into 1/2" stock. Then attached them to 1/4" support plate. Pics are coming soon.

[bill-costa rica]

glen
when are you headed to alaska ?

bill-cr

[Sierra Sam]

Ohhh... so it's dropped, not drooped?
Well, I guess droop works at that...
as in negative (recessed), vs. positive (raised)?

Glen -Gotst any pics of yer wurk?

[micropedes1]

I gotta put together one more before I head north in the next few days. I'll try to shoot ya some pics as I put it together.

Sure do wish you were going with this year, Bill. I need some experienced company!

[bill-costa rica]

way to cold for me, i like these nice warm rivers

bill-cr

[micropedes1]

I started with 1/4" polycarbonate. Cut to 6" width. Then glued 2 of them together to get the 1/2" lamination. You can then use a GOOD table saw to rip the 15 degree taper on each edge. Then cut to width. (I cut mine 2" wide). See 1st pic


When ya get a supply of tapered stock, then you can start to glue it down to a smooth sheet of polycarbonate using standard PVC heavy duty cement. Start with about 12" of slick zone prior to riffles. I alternate slick settling area with riffles. See pic 2.

Looks rough til you block sand the tapers. Or size it to your sluice and let the gravel do it for ya.

[russau]

now theres imagination and inginuity in progress!