Expanded Metal Classifier - best design?

[Joel1316]

Hello All, I found some expanded metal on sale at a local hardware store for $13.00.
I think it was 24X36 with 3/4" holes. I wish the 1/2" holes were on sale too, but not...
I want to be able to shovel material and have the expanded metal classify out the large rocks/gravels. At first, I was just going to build a frame and lay it flat, but I would have to empty out the large rocks...
Now I'm thinking of building a frame, lay at an angle and have some sort of hopper at the top to make sure all material was able to tumble down for the whole length of the expanded metal. (The hopper would have a large hole).
Before I start building this, I'd like to get more ideas? I hate classifying!

 

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[Fullpan]

This is simple classifier I threw together for dry gravel - it worked great! But if I did it again, I would make it with two
sizes of expanded metal.

 

[Goodyguy]

Get used to classifying, it's the bread and butter of recovering more gold.

 

[Joel1316]

Classifying is here to stay, just trying to make it as painless as possible and reduce the required work : )


Fullpan, that looks like the area I usually prospect in. Does your classifier do a good job of tumbling the rocks enough to seperate dirt from rocks?

 

[Fullpan]

Yes, but that's on the "sunny" side of the canyon where the gravel gets bone dry in summer, and there's not a lot of clay to stick to the larder rocks. The pic
was taken years ago when I was a lean, mean mountain goat on the South Yuba River, about halfway between Washington and Edwards Crossing. I used to
average about two dwts a day, using this screener and a sluicebox.

 

[Goodyguy]

Classifying is here to stay, just trying to make it as painless as possible and reduce the required work : )

I hear you...... That's why I like using my trommel and my bazooka sluice.
And I even made an automatic classifier that uses two 18V orbital sanders as vibrators. (works wet or dry) Has 3 tiers. First tier has 3/4" expanded. second tier has 1/2" expanded and third tier has 3/16" punch plate.

GG~

 

[KevinInColorado]

GG you are amazing, that sounds SO cool!

 

[Joel1316]

I hear you...... That's why I like using my trommel and my bazooka sluice.
And I even made an automatic classifier that uses two 18V orbital sanders as vibrators. (works wet or dry) Has 3 tiers. First tier has 3/4" expanded. second tier has 1/2" expanded and third tier has 1/8" punch plate.

GG~

If I had the money and muscle to carry around a trommel, I'd kill to have CA Sluice's hand trommel.

GG, you just turned on a light bulb in my head. I owe you at least a soda! : )
Instead of sacrificing an orbital sander, could we make our own vibrating motor? 12V DC motor, mount a metal or wood disc (not centered) onto the shaft of that motor, then mount the motor onto what needs to be vibrated? I just need to figure out how big the motor needs to be and how long a 12v SLA battery can run the motor.

 

[walldo]

I like the small trommel idea. Here in Washington most places I go to are to far to pack something like that in. Still want one. Cool tool factor.

 

[jcazgoldchaser]

Hello All, I found some expanded metal on sale at a local hardware store for $13.00.
I think it was 24X36 with 3/4" holes. I wish the 1/2" holes were on sale too, but not...
I want to be able to shovel material and have the expanded metal classify out the large rocks/gravels. At first, I was just going to build a frame and lay it flat, but I would have to empty out the large rocks...
Now I'm thinking of building a frame, lay at an angle and have some sort of hopper at the top to make sure all material was able to tumble down for the whole length of the expanded metal. (The hopper would have a large hole).
Before I start building this, I'd like to get more ideas? I hate classifying!

Google "metal supply {town name}", you'll find better options than the HW store.

I sifted a lot of soil in the back yard with a 1/2" mesh 2'x4'. It was made like a coffee table. Toss in a couple shovels, shake it back n forth, then flip it over.

Picture 2 2x4 screens. 1 is highly sloped into the other which is mostly flat. Toss a load at the slope and it tumbles down onto the other. Then be able to flip up the bottom one. That way any material which didn't fall through the top, will fall through the bottom.

 

[Goodyguy]

If I had the money and muscle to carry around a trommel, I'd kill to have CA Sluice's hand trommel.

GG, you just turned on a light bulb in my head. I owe you at least a soda! : )
Instead of sacrificing an orbital sander, could we make our own vibrating motor? 12V DC motor, mount a metal or wood disc (not centered) onto the shaft of that motor, then mount the motor onto what needs to be vibrated? I just need to figure out how big the motor needs to be and how long a 12v SLA battery can run the motor.

Not much of a sacrifice..... they cost 7.95 ea. at Harbor freight without batteries. I just connect them to a 12v deep cycle power chair battery and they will run all day.
The problem is the noise from all the vibrating.

Plus if you are going to run dual sanders the off sets need to be synchronized or else they may balance each other out.
They must also be tied together where the batteries would go as well as being screwed down to the mounting plate.
(unscrew the sanding plates and discard them then use the same screws to mount the sanders through the mounting plate.)


Now you can connect the whole unit to anything that needs severe vibrating.

 

[Goodyguy]

I like the small trommel idea. Here in Washington most places I go to are to far to pack something like that in. Still want one. Cool tool factor.

You can build a lightweight one for $50 here's the plans: Mike's Hand Trommel

 

[TerryC]

I hear you...... That's why I like using my trommel and my bazooka sluice.
And I even made an automatic classifier that uses two 18V orbital sanders as vibrators. (works wet or dry) Has 3 tiers. First tier has 3/4" expanded. second tier has 1/2" expanded and third tier has 1/8" punch plate.

GG~

Hey GG, not to highjack the thread but I truly would like to see a pic of your machine... and any tips if you can. Tnx. TTC

 

[Goodyguy]

Hey GG, not to highjack the thread but I truly would like to see a pic of your machine... and any tips if you can. Tnx. TTC

The automatic classifier I was referring to is the top half of my Gold Daddy
Classifies into two 5 gallon buckets

The chute empties the minus 1/2" to plus 3/16" gravels into the outside bucket for nugget inspection.
Works either wet or dry.



Since the photos were taken I have welded valve springs to the legs at the base and dual vibrators to the top
I changed out the 1/8" stainless mesh on the bottom tier to 3/16" punch plate.
I also added a chute below the top 3/4" expanded tier to empty tailing gravel off to the side.
(The 1/2" expanded center tier empties off the back side)


My advice is if you build one make sure all parts are solidly and ridgedly connected for maximum vibration transfer.

* a tray runs under each of the top two classifiers stopping 6" from the bottom end of each.
The bottom 3/16" punch plate has a dual hopper under it to funnel the concentrates into each of the two buckets.
The classifiers are set to 3" of drop to the foot (approx 15 degrees)


GG~

 

[Joel1316]

Not much of a sacrifice..... they cost 7.95 ea. at Harbor freight without batteries. View attachment 712995 View attachment 712996

That is great! Thank you for the pictures! I will have to check out my local Harbor Freight for those sanders. I searched high and low for just vibrating motors and could not find any decently priced motors. Thank you for sharing your idea

 

[rodoconnor]

GG, Have you ever read KVM's Vibrating Gold Cocentrators? If not you should. You might glean an idea or two. Good job BTW

 

[Goodyguy]

GG, Have you ever read KVM's Vibrating Gold Cocentrators? If not you should. You might glean an idea or two. Good job BTW

Could not find an available copy other than one in a library 1000 miles away....... still looking

 

[Fullpan]

GG - It looks like the sanders can be mounted right onto a sluice box or highbanker sluice also. Maybe that's what KVM's book is about?

 

[jcazgoldchaser]

GG - It looks like the sanders can be mounted right onto a sluice box or highbanker sluice also. Maybe that's what KVM's book is about?

Simple axle with offset weight, such as a pulley with some holes drilled in 1 area...

 

[Goodyguy]

That is great! Thank you for the pictures! I will have to check out my local Harbor Freight for those sanders. I searched high and low for just vibrating motors and could not find any decently priced motors. Thank you for sharing your idea

I should state that even after adding the second sander I still only use one at a time. One is really all that is needed as long as the battery end is connected to the plate, something I only discovered after mounting the second sander. But now I have a spare for backup if needed.