DIY Miller Table

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Boulders

Theo Nestora
Joined
Dec 15, 2016
Messages
172
Reaction score
103
Location
Sydney, NSW
Even though I have a Spiral Wheel I still have problems in separating the black Sand from Fine Gold.

I was about to get started on the Blue Bowl when I looked over to my desk and there was a sad lonely paper / document tray sitting there screaming to be made into a Miller Table. I had a piece of Cutting mat there also and a few backup aquarium pumps lying around.

So I went downstairs and started drilling away, got a couple supplies from Bunnings for a total of $7.00 and away we went.

I had a can of Contact cement sitting there which i used to glue the mat to the tray. Here is the finished product. I did a quick video also to see it in action.

I still need to fit some adjustable legs and drill the holes out a little bit more in the spray bar but all in all it works well for a first attempt.

Here are some pics and a link to video:

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[video=480,360]https://youtu.be/FR75v-bV3pU[/video]
 
Just noticed when i shut it down the gold has a tendency to pick itself up and start sliding. Any way to avoid that? Thinking of changing the cutting mat over to rubber cupboard lining sheet.

Any thoughts or suggestions?
 
Yeah I might give that a go. I might use the stuff you gave me.

Here's a pic of that cupboard lining stuff that has a diamond shape in them.

Any opinions on this stuff.

1483080209_20161230_173830_resized.jpg
 
not sure about that one and i think the stuff i gave you might be to big of a v in it have a look around for some finer stuff
going back up there tomorrow to finish that hole
 
Hi Boulders

did you end up finding a good solution for the separating mat?

considering something like this as well at some point.

Regards
 
Yet to test it out yet but from what I have learnt is that the angle of the table and the flow of the water is very crucial in getting it to work correctly and has very little forgiveness if one or the other is out slightly.

Classifying the material is also crucial in getting it to work right

I have recovered almost a gram of flour gold that the Spiral wheel just couldn't pick up but I must admit it is pretty time consuming
 
Also if you are planning on making one put the water intake along the back in the middle and then 'T' it off. It will give you more even water pressure along the pipe. Mine seems to have more water flowing from the intake side than the plugged side. I'm going to try and compensate a little by drilling larger holes on the plugged end of the spray bar.
 
Just a couple of things you could try;
Lightly paper (1200 wet & dry) the document tray until the water flows unbroken across the face
lightly sandpaper the cutting mat surface
change to flat rubber surface
a weir may help resolve uneven flow across the table

Apparently slate is the preferred surface but it is hard to find in a nice flat piece.

I have tried chalk board paint, it works but has 2 issues, it needs the correct substrata or the paint flakes and it is difficult to get a perfectly flat paint surface. Tried vee mat but could only find 2mm stuff, it held too much Haven't tried that stuff used in caravans to stop plates moving.
Blue bowl, you need to rerun several times because there always seems to be very fine gold in its tailings which requires water flow adjustment.

The diamond mat held too much black sand and was hard to get flat when I tried but maybe I was not creative enough.

Be great to see your solution.

Barry
 
Great info there Barry. The cutting mat seems to grip the fine gold pretty well as is.

I'll definitely give it a light sand and see how it goes and make a weir.

Good advice mate. Thanks
 
So I've added a little mod. Printed out a bracket for a motor mount to vibrate the table. Had an unused RC motor lying around so I hooked it up to the table.

Will post results after I give it a wet run. Here's a couple photos of the motor mounted with an offset weight to create vibration.

Once I do the couple mods that I think it needs and have it running as it should I'll do a proper video on it in operation.

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I gave it a quick squirt. Definitely needs either some grooves up top to hold the Gold or a hole with a catch can underneath to brush the Gold into.

Here's a little dodgy video of the concept. The vibration actually pushes the Gold back up the hill so it has potential.

Also need to play with water flow and get a weir in there for even water distribution.

Still in prototype stage so no editing.

[video=480,360]https://youtu.be/KJu-7Abs91E[/video]
 
Damn you are pretty handy Boulders, getting some nice colour there too.
That cupboard lining is interesting, kinda looks a little like that Martin Gold Stop Mat.
Also Rinse aid is a surfactant that reduces the surface tension of water, a drop or 2 will help with floaters and maybe the drag you are experiencing from when you shut the water off? In the US/Canada its that Jet Dry not sure if we have the stuff here, but dishwasher Rinse Aid is the same thing.
 
You have a great idea there, but maybe try mounting the motor 90deg to what you have done.
The way it's positioned now it appears to provide sideways jogging.
When you tap a gold pan it's from the top directed down. So if you mounted that motor 90deg to what you have done, those shock waves will travel down the board, instead of across it.
It may or may not work better, worth a try.
Something else to consider would be a motor mounted away from the miller table and only contacting the back of the table when the eccentric is at it's furthest extent. Thus creating that TAP motion, rather than a continual vibration from a device fixed to the board.
 
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