suction dredge newbie

[digger pat]

So I'm building my own suction dredge. budget is pretty much non-existant. so far this is what I have. I would like opinions on wether or not what I'm putting together will work?
I have a Keene A52 sluice box, A 5.5hp honda 3" pump that I'm going to reduce to a 2.5", due to the fact that all the free hose I have is 2.5". I am currently trying to build a flare out of heating/ac duct. 30" long, flattened down to 8" at the sluice end. and 2.5" where the hose will come in. The Suction nozzle is going to be 2.5" stainless. with the pressurized 1.5" line being reduced from 2.5" at the point of hose and nozzle. I havnt yet started on floatation or frame.
any tips, opinions are welcome!! I'll take all the advise I can get. I just want to get this thing built and get it out on there!
thanks!

[digger pat]

Another question...what is the correct angle that the flare be comming into the sluice at?

[digger pat]

Another question...what is the correct angle that the flare be comming into the sluice at?

[Hoser John]

Red traffic cones make ez 2 do flares,just squish. Flare angle of input dependent on water depth,adjustable degree of induction is the best but anywhere from 15 to 30 degrees seems the norm. Tooo long and you get into water depth hassles,too short and cavitation, and laugh my arse off straight in like rwonder = missing the box purt' near completely-John

[digger pat]

How do the traffic cones hold up to the material running over it?
Does it wear out fast? if they do weve got plenty of construction goin on around here! lol
man.....I get questions popping up all the time.... how much drop should there be from the
end of the flare down to the sluice box? if the end of the flare is a little higher,
it should create a small eddie before the black ribbed mat. correct? is this helpful or does it interfere
with fine gold recovery across the black mat?

[Hoser John]

you'd be absolutely amazed at the abuse they'l take