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Geo2
09-23-2012, 10:17 PM
Hi, I've been thinking for quite time about an idea that for us (hobbyists' and the like) can try,
What I propose is this: can a billiard table used as a concentrating table -slate one I mean - ? I know I am not the first may be who thought about that :p

I recently came about a great topic by Bill Bohan
http://www.akmining.com/forums/showthread.php/803-eight-ball-in-the-corner-pocket-Check-out-my-prototype-slate-table

that idea is very similar to what I am building :cool:
I wonder is it possible to use the whole billiard table or part of it?
it is long : 8 ft (2.4 m) !
The surface is made of solid slabs of slate with some scratches on it. What is best length of a slate table that works on fine grained ore (hard rock crushed and screened to -100 mesh) ? I intend to paint it with chalkboard paint.
Any suggestions here? :confused:

AK Nugget
09-25-2012, 08:27 AM
Has anyone tried Solid Surface material, ie. Corian®? It's relative flat and can be surfaced to most any type of finish from rough to highly polished.

Neal

bmborum
09-25-2012, 05:34 PM
They are very efficient for very small gold and fine stuff, not designed good for any big stuff. If you paint it with chalk board paint you can use anything fairly smooth, like corian, slate, glass, etc. the trickiest part is getting it painted without it running. The biggest key to them working (and they work very well - far better than a wheel) is a smooth even flow of water across the entire table

Geo2
09-26-2012, 09:37 AM
Has anyone tried Solid Surface material, ie. Corian®? It's relative flat and can be surfaced to most any type of finish from rough to highly polished.

Neal

Hi, Neal. This the first time I heard about this material.Could possibly be a good alternative.Un-fortunately it is not available in my area. :(
Thanks anyway.

Geo2
09-26-2012, 09:44 AM
They are very efficient for very small gold and fine stuff, not designed good for any big stuff. If you paint it with chalk board paint you can use anything fairly smooth, like corian, slate, glass, etc. the trickiest part is getting it painted without it running. The biggest key to them working (and they work very well - far better than a wheel) is a smooth even flow of water across the entire table

Thanks bmborum for the info :) And yes painting is a key to fine gold recovery on smooth material. By the way , is length of the table has any special role in recovering fines ? what is best length do you recommend? I intend to use a 12 Bilge pump.

N2Au
09-27-2012, 05:16 AM
Tips for a Miller table... (NOTE: I do not consider myself an expert, as such, these coments are probably worth about what you paying for them...

Principle of Operation..
In a sluice box, gravity is the primary force that separates the gold from the other materials... On a Miller table, Friction is the primary force at work... (Gravity plays a part, but friction is force to be managed)

1) Gold can not absorb water, so, water will not "stick" to its surface like it does on almost everything else in your concentrates (like beads of water on a freshly waxed car). So, in the water flow, the surface of the gold particles will have a lower drag coefficient (friction) than anything else in your concentrates.
(The shape of the gold particles does come into play, but dealing with this is balancing diminishing returns.)

2) The "trick" is to balance the friction forces (find the sweet spot) so there is enough friction to move everything but the gold...

Water Flow...
When Miller tables are discussed, most of the conversation is about the table's surface (which is important), however, in my opinion it is a "properly controlled" water "flow" that will determine how well the table works. (By water "flow", I am referring to all aspects of the flow, not just the volume of the flow.

As it is the water flow that creates the friction, you must be able to control the various aspects of the water flow precisely... The water flow should be uniform across the surface of the table, even, smooth, and non-turbulent, think of this as a "single" sheet of water "sliding" down the surface of the miller table... it should look as smooth as glass on its top surface... (it will get a little "rippely" as the water accelerates down the slope, but that’s ok... if it is running right, most of the "capture" action will occur within 6 inches of the infeed point...

I use a gate valve rather than a butterfly valve to control the volume of water. I control the rest of the flow attributes by starting with feeding the water into a small "header tank" (the width on the table) to stabilize the head pressure across the width of the table. The header tank discharges on to the Miller table through a full width x 2-inch long x 1/4 in thick section of corrugated plastic sign board. The small square channels create an even, non-turbulent, laminar flow.


Length of table...
In my opinion, most Miller tables are much longer than they need to be (even my own). I made mine 1 foot wide, and 3 feet long... I wish it was 3 feet wide and 1 foot long ! A miller table's "action process" has only one speed ... SLOW, it cannot be speed up or slowed down... (You can only do more of it, i.e. … a wider table)

3) In feed of concentrates...
I often see Miller tables feed with a spoon... well.. that works... but it is not very efficient. This approach reduces the effective working area of the table, and, it creates micro-turbulence... Slowly sprinkling a thin layer of (pre-wetted) concentrates into the flow works better for me.. (I use a pulsed vibratory full width feeder, because I am lazy)

4) A fine bristled, 1-inch paint brush works great to manually move material around on the table's surface while it is running, but when you get is set up perfectly, you should just let it run..

All of these things are just for your consideration.. a super-simple, not-complicated miller table will work... a more sophisticated miller table will work better, but is not absolutely necessary.. (I got by for years with a super-simple, spoon feed set up... but as the volume of my concentrates grew.. I needed a better, more efficient solution.

I have tried a lot of other things.. and then came back to the miller table… they are not fast.. they are not sexy… but , in my opinion, it’s hard to beat a properly operating miller table for separating micro-gold from concentrates…

chickenminer
09-27-2012, 10:58 AM
Might want to read this thread..

http://www.akmining.com/forums/showthread.php/2236-Miller-Table

tenderfootminer
09-27-2012, 11:11 AM
I recently bought a black magic table for my boys to play with "the fines" it works great and was cheap not slate but a stange rubber compound....as with any table or wheel jet dry is a big key breaks the water tension so it lays out on table like glass and you can turn back the flow http://i372.photobucket.com/albums/oo165/tenderfootminer/blackmagic.jpg

Geo2
10-01-2012, 12:03 PM
Might want to read this thread..

http://www.akmining.com/forums/showthread.php/2236-Miller-Table

That's an Interesting thread ! Thank you

Geo2
10-04-2012, 01:51 PM
Tips for a Miller table... (NOTE: I do not consider myself an expert, as such, these coments are probably worth about what you paying for them...

Principle of Operation..
In a sluice box, gravity is the primary force that separates the gold from the other materials... On a Miller table, Friction is the primary force at work... (Gravity plays a part, but friction is force to be managed)

1) Gold can not absorb water, so, water will not "stick" to its surface like it does on almost everything else in your concentrates (like beads of water on a freshly waxed car). So, in the water flow, the surface of the gold particles will have a lower drag coefficient (friction) than anything else in your concentrates.
(The shape of the gold particles does come into play, but dealing with this is balancing diminishing returns.)

2) The "trick" is to balance the friction forces (find the sweet spot) so there is enough friction to move everything but the gold...

Water Flow...
When Miller tables are discussed, most of the conversation is about the table's surface (which is important), however, in my opinion it is a "properly controlled" water "flow" that will determine how well the table works. (By water "flow", I am referring to all aspects of the flow, not just the volume of the flow.

As it is the water flow that creates the friction, you must be able to control the various aspects of the water flow precisely... The water flow should be uniform across the surface of the table, even, smooth, and non-turbulent, think of this as a "single" sheet of water "sliding" down the surface of the miller table... it should look as smooth as glass on its top surface... (it will get a little "rippely" as the water accelerates down the slope, but that’s ok... if it is running right, most of the "capture" action will occur within 6 inches of the infeed point...

I use a gate valve rather than a butterfly valve to control the volume of water. I control the rest of the flow attributes by starting with feeding the water into a small "header tank" (the width on the table) to stabilize the head pressure across the width of the table. The header tank discharges on to the Miller table through a full width x 2-inch long x 1/4 in thick section of corrugated plastic sign board. The small square channels create an even, non-turbulent, laminar flow.


Length of table...
In my opinion, most Miller tables are much longer than they need to be (even my own). I made mine 1 foot wide, and 3 feet long... I wish it was 3 feet wide and 1 foot long ! A miller table's "action process" has only one speed ... SLOW, it cannot be speed up or slowed down... (You can only do more of it, i.e. … a wider table)

3) In feed of concentrates...
I often see Miller tables feed with a spoon... well.. that works... but it is not very efficient. This approach reduces the effective working area of the table, and, it creates micro-turbulence... Slowly sprinkling a thin layer of (pre-wetted) concentrates into the flow works better for me.. (I use a pulsed vibratory full width feeder, because I am lazy)

4) A fine bristled, 1-inch paint brush works great to manually move material around on the table's surface while it is running, but when you get is set up perfectly, you should just let it run..

All of these things are just for your consideration.. a super-simple, not-complicated miller table will work... a more sophisticated miller table will work better, but is not absolutely necessary.. (I got by for years with a super-simple, spoon feed set up... but as the volume of my concentrates grew.. I needed a better, more efficient solution.

I have tried a lot of other things.. and then came back to the miller table… they are not fast.. they are not sexy… but , in my opinion, it’s hard to beat a properly operating miller table for separating micro-gold from concentrates…

Very informative post ! regarding the length of the Miller table I might consider reducing my prototype length. Thank you N2Au