Centrifuge Project - Possibility.

Originally Posted by sawmilleng

Alloy,

That is pretty nice Fraser River gold! I've done panning and sluicing years ago as a kid but probably further down the river than your photos--they've gotta be from the Quesnel area where the big stuff comes from.

I was doing my panning in the Lillooet area but the gold there is referred to as "colours"; fine powder that is overwhelmed with black sand. Never did find out what the black sand assayed out to, but it was supposed to have a little platinum in it as well. Not worth chasing when its that fine!

I remember watching an outfit that did some testing work in the area--they washed the gravel down to the fines and ran it through a device like a cone shape, with the pointy end down, and the inside of the cone having flat rings around on the circumference, like the riffles in a sluicebox. I can't remember if it vibrated or rotated. I think it rotated, not very fast, and the fines and water were introduced in the center of the bottom and worked their way up the insides of the cone, over the riffles. Presumably the light material washed out and over the top edge. Maybe you know what I'm talking about...could have even been an early attempt at using centrifugal force to help separate gold.

I remember them all drooling over the black sand they recovered after a day of using this magical sluice. They packed up the next day and never came back.

Jon.

Jon when your looking down into the bowel the way the rings are cut and welded into place make it looks like an inverted cone.

By chance do you remember what colour the machine was painted, all of Don's were painted blue.

From the specifications I gave in my first post you will note that the rotating bowel produces 70 G’s at 640 rpm.

The manufactures remaining in business have abandoned AR ( abrasion resistant ) plates in favour of a injection moulded poly cone which is subject to wearing out much quicker adding to the cost of operating the machine.

I would love to post a picture of the 12 inch unit but the picture has someone standing beside the machine who wouldn't want the picture published. I have to respect their request for privacy. Anyhow this does not stop me from giving a description of the machine.


The 12 inch centrifuge is mounted on a mobile cart, and has a classifier, vibrating deck that feeds into the bowel. One modification I'm going to make is the use of a variable frequency controlled IP67 ( wet service ) 3 phase stainless steel phase electric motor which almost everyone has switched over to. They however to keel manufacturing costs down have opted out of using the higher cost stainless steel cased motor.

Then another modification of my own design to the rings that will permit a much faster clean up.

I see your in the Kootenays if you have a claim nd would like to hook up for a week or two to fool around with one of the centrifuges once I have a machine completed PM me with your contact details.

You need a materials engineer, someone who knows what certain parts need to be manufactured from for maximum durability. Even at 70g has nobody considered the use of coatings? Silicon carbide can be "coated" to a variety of high strength metals. If you manufacture from plastics, the obvious choice for abrasion resistance and natural lubricity would be Delrin.

Delrin is the wear pad material found on forklift sideshifter mechanisms, crane wear and stage pads, delrin is also often used to prototype because it is quite strong.

Originally Posted by armygreywolf

You need a materials engineer, someone who knows what certain parts need to be manufactured from for maximum durability. Even at 70g has nobody considered the use of coatings? Silicon carbide can be "coated" to a variety of high strength metals. If you manufacture from plastics, the obvious choice for abrasion resistance and natural lubricity would be Delrin.

Delrin is the wear pad material found on forklift sideshifter mechanisms, crane wear and stage pads, delrin is also often used to prototype because it is quite strong.

This centrifuge has an 18 year history behind it to back up its performance which has proven out time after time to do as it was claimed to do. There have not been any new machines built since around 2003 but you'll still find them in the field recovering gold along with the odd one showing up for sale.

So I'm not about to dumb it down with plastics to save a few dollars over purchasing the more expensive AR plate.

If I needed a materials engineer I would contact the University or use google scholar to search for whitepapers related to a questionable material.

Abrasion resistant plastics, http://scholar.google.ca/scholar?hl=en&q=abrasion+resistant+plastics&btnG=& as_sdt=1%2C5&as_sdtp=

What would be in my best interests would be to hire someone with a good track record in global marketing to generate revenue from sales.

Your concerned with 70 G's of artificially produced gravity then my small 6 inch centrifuge would have you running for the hills with it's 500 G's generated from a bowel spinning at 2500 revolutions per minute. And this bowel was made from poly.

On a side note: Delrin is also used in hip implants and heart valves.

This is valuable and interesting content for those of us who refine and even for the maximum recovery members. I think it is time for a recovery and refining section. maybe only make it available to members. Reason one would be to keep potently dangerous info from the hands of those who don't take the time, or effort, to fully educate them selves. I for one appreciate A2s knowledge and willingness to share but I see coming down the line some one with lessor knowledge or care posting some very potentially dangerous info regarding recovery and refining to those less educated or less caring.

Let me rephrase: I had made an assumption that you planned to manufacture or source a manufacturing house...which led me to believe you wanted to engineer it for maximum product life over lowest cost to manufacture. Correct me on that if I am wrong here.

My concerns and yours are probably the same, I was using the effectively generated force as a reference, the same as you would from light versus heavy pressure on a piece of sandpaper. These are probably out of the scope of the product, things like coating and certain kinds of plastics. That is found more in specialty manufacturing where precision and longevity are the main factors. Still, I'd appreciate a little less condescension, you may google it, I studied it and earned a degree. I was honestly trying to tell you that a consultation by a firm might save you thousands (or hand over a foot here...) possibly improve your product over it's predecessor. I know how these things work, wouldnt be nice to increase material processing rates without increasing machine size...or cost. More clients, more effective word of mouth in an industry that's alot like forestry, guys get set on using a particular process, manufacturer etc. Just my idle banter on that subject, was trying to help.

((Got a PM explaining who you were, I never saw alloy2 before so made the assumption he was a newer guy and wanted to ensure the forum was getting it's due service. My apologies))