New Zealand Gold Prospecting & Metal Detecting Forums Archive

Does anyone know the right angle to set your ripple strips at......
Just watched the full series of Gold rush Alaska....so interesting

hi gohard
ive been making slice boxes for a good 40 years all different but my latest one seems to have worked the best
if you study the flows of river and water you will note that one needs to vary the flow to stop the gold falling over the riffles
if all riffles are the same them gold will move over each in turn if one changes slope and angles heights and shapes then the water will take on different charatoristics you also have to take into account the area working because different gold will sink or flow differently according to sise and weight

summary there is no hard and fast rules as far as im concerned
i have 12 riffles in the top half of my box and they are all diferent

Like Kiwikeith I have made sluice boxes for forty years and by the standards I see on the various forums they are all rather primitive and I really dont want anyone seeing photos of them as they are 'that' primitive BUT they work. Back when I was a kid the grand favourite for matting was Coir matting. Thhis came in different shapes and forms if I remember correctly. On large sluice boxes the old Coir front door mats were cracker and on smaller ones woven Coir matting was the order of the day.
We also used standard longer pile carpet. Other people used other material and I have even seen jute sacking used.

My first sluice boxes were wooden and heavy but later I made them from Aluminium. Today I only have one sluice box and its a short thing with sides about eight inches high, about eight inches wide and about four foot long - made from two sections of an old type main frame computer housing joined end for end with small angle iron riffles and woven Coir matting in the bottom.

One old guy in his 90s had a sluice box which I am looking at a photo of right now - It has the same width as mine more or less but is wood, not as high as mine and possibly longer as the photo doesnt show the end. The riffles are the same distance apart as their width and height half of the width. Now this guy DID know what he was doing. The photo shows what I believe is a days work, more gold than 99% of people in this forum will get in their lives - two to three hundred ounces and by guestimate the riffles each have in them from the top end 40, 30, 40, 40, 40, 10, 5, 4 then just a smattering of gold.

There is NO set rule for sluice boxes I dont think - it is what works best for you in the conditions and situation in which you work.

My underwater dredge has a sluice box section about seven inches high by about six or seven wide, the mouth of the dredge is six inches, the pump puts through 300 gallons per minute and the suction at the front is enough to possibly break or dislocate fingers if the hand was drawn quickly onto the entrance by the current - I know that I had hurt my fingers on several occasions. A friend once said that I would lose a lot of gold with the force of water that went though it and thought he would make a mint out of what came out the rear end - but he never found a thing - it seemed to work a treat.

Edited by user Thursday, 8 September 2011 10:52:26 PM(UTC)  | Reason: Not specified