Punch Plates Options

[tlcarrig]

Can anyone here give me a definative reason for the use of a punch plate in a sluice or rocker box. I can see using one in a highbanker or dredge but i don't see the need for one in a sluice. Am I off base here or am I thinking streight?

[russau]

using a punch plate helps screen off the larger rocks/gravels and keeps the finer material in the sluice from being displaced from the bigger gravels. Leonard has a good example on one of his videos or Dr. Sluice and his sluicing methods using a screen at the front of his sluice to remove the bigger gravels. and he does real good ussally sluiceing!

[redrum]

What is a sluice, but an unpowered dredge or highbanker? The key is CLASSIFICATION.
Classifying as close as possible to the size material you want to recover, within reason.
Larger rocks etc. create eddies and vortices that drag smaller material with them out the end of your sluice.

[CP]

I agree with the classification being needed for sure.......but I disagree with putting it in the sluice itself.
We classify before the sluice (in the bucket) and thus we do not interfere with the delicate flow set up in the sluice. Sluice boxes are designed to run a size of material......dredges and highbanker are as well but designed differently than a sluice design. Highbankers use the grizzly/crash area and dredges are designed to the hose size vs. flow and also have a crash/header area.
The idea when sluicing is the same yes but using natural creek flow you want to keep the controlled area (sluice box) as constant as possible for maximum recovery.......putting a punch plate in the box itself and then adding material has always proven to be disruptive in the sluice flow to us with just the natural flow in the creek set ups.
On the up side to classifying in the bucket........You get more useable/paydirt material to the box.....and you carry less of the rock weight.

CP

[tlcarrig]

I tend to agree with CP here. My feelings are that one is not really needed in a sluice or rocker box because (hopefully) your material will already be classified to a certain size. Usually 1/4- or 1/8- or smaller. In a highbanker with grizzly, a dredge with crash plate and a trommel, a punch plate is necessary because your material is being classified by the equipment. I might be off base here. What do ya'll think? I'm really trying to justify NOT putting one in a rocker box I am building. I plan to build a small high banker that will definately have one.

[Denise]

We have some great info in our Plans and Tips page about classifying.

Also instructions on making your own high volume bucket classifiers.
Ours works great...... and fast! I wouldnt go prospecting without it!