Home made riffles. Do's and Dont's.

Knocking up my latest sluice box, I thought I was at the easy stage of making and fastening the riffles, Man I was wrong!
Loved the idea that you see so often, where all the riffles are welded in a lift up hinge type set up, seemed perfect and so simple for clean up time. Then the down side hit me and I cant get past it!
The whole idea of your sluice and all the riffles is, and providing your angles are right, A large percentage of your gold will be caught at the first or second riffle, by the last riffle if your not using carpet to trap the supper fine gold, there should be nothing, and if there is your running to big an angle or to much water!
So where's the problem? The problem is sealing each riffle to the bottom of your sluice etc, so No water can bypass underneath! Any gap underneath will allow your gold to go from one riffle to the next. Vibration's alone will allow this confusing scenario! When you stop to do a clean up and find you have lots of gold near the end of your sluice, what's the first thing your going to do "Reduce the angle" Your next consecutive clean up's will be a nightmare because most of the waste hasn't washed out and you still have gold near or at the end of your sluice box! Or No Gold at all?

Hi Someday,

I probably missed something, but wouldn't that be what the carpet is for under the riffles?
Besides snagging little gold, it's a compressible cushion that takes up the space between the riffles and the bottom of the box
thereby stopping water flow completely under them.
Or are you planning on making a box without a carpet?

All the best,

Hi Flakmagnet. I'm not convinced at all, that carpet or even rubber could guarantee no gaps under riffles when riffles are attached to a movable frame? In my view only the last riffle could come close to guaranteeing no gaps! Maybe I'm wrong, Unless every thing is built out of 1/2 inch thick steel, I cant see it happening?

someday wrote:Hi Flakmagnet. I'm not convinced at all, that carpet or even rubber could guarantee no gaps under riffles when riffles are attached to a movable frame? In my view only the last riffle could come close to guaranteeing no gaps! Maybe I'm wrong, Unless every thing is built out of 1/2 inch thick steel, I cant see it happening?

Someday mate it all comes back to how there locked down. I use a hinged setup on my gear which locks down very well indeed. { the idea was passed on by a very good mate of mine} I wish i had more time to take a photo of the setup but i don't sorry mate but they do lock down very well. cheers

I'll take your word on that one! I've gone back to the old fashioned way of bolting each riffle down separately! Maybe I just saw to much into the process ?

I think you might be a touch too deep in the process...
not that there is anything wrong with that but somewhere along that path
you hit a point of diminishing returns.

The riffles on the four dredges and the innumerable sluice boxes I have used,
all had one-piece riffle systems that hinged and locked down onto carpet.
The only time I can remember getting material under it
was when, as James101 mentioned, the hinges were not fastened down properly...human error.

Once material hits well-angled riffles and a good carpet, as long as the box is at the right angle
and is not being overloaded with material or flooded with too much water, the gold stays put.

Some people can start getting pretty focused on micro-gold.
That seems to appeal to a certain very precise mine-set,
I opt out at that level...must be my a.d.d. or something

All the best,

I wouldnt worry too much about a small gap under it. My riffles are on top of expanded metal , and under that is ribbed matting. The metal is 2mm thick and i guess the ribbed matting is 1.5mm. I have been running it for 15 days out of the last 21, with a large bucket under the end of the sluice just to make sure, and i didnt lose a micron. Aftre panning the heavies in the bucket.
I have one wingnut holding down the second riffle that i was worried about water disturbance with, but its not an issue..
After the riffles i am running a door mat with round holes with carpet under that for the fines. I will post a pic of the gaps i have in mine. By the time you drop your first shovel in the gaps are filled with little iron stone pebbles , and even without the gap filled you still get a low pressure behind the first riffle.
The weird part is not one piece even got to the first riffle in my sluice, other than the very very fine micron gold.

I guess you guys are right, I'm looking too deep, and yes Flackmagnet Supper fine gold is in my blood and I would hate with a passion to not see it remain in the sluice, there's just so much of it ,to waste it! The way I see it, water is supposed to go over the riffles to have any effect in concentrating gold?
My old sluices were made out of timber, which was easy to fasten down riffles! Making a sluice from beer can material is proving a different problem!
My hope is, the riffle section will have almost nothing to do with my gold recovery, but until I'm satisfied with my adjustable bits, I need to be sure the riffles are going to do their job!

Mate i am home for a few days i will post a photo of my setup for you. cheers

Thanks James, would be good to see!
I guess my main concern is volume without having to check! If I can't put in an hours worth of full time shoveling without worrying what maybe lost, then I'm not happy with the setup!
Cheer Chris.

Chris
Mate this is the best setup for working pepper gold, we have been using it now for years. The matting which is used well that comes back to personal choice they all work much for muchness. What I like about the wing nuts is you can control your cleanup by sections. Cheers mate



P.s check
https://golddetecting.forumotion.net/t3854-updated-banjo-highbanker-plans#43623 for the hinged riffles. cheers