2021....

[Moneybox]

Backhoe here....

https://www.daviesinternational.com.au/product/580d-case-4x4/

Thanks for that but I think I would be just taking on another project. I'll buy something that's up and running and my price range leaves me with a Chinese special. I know in the long run it most likely won't outlast the used better brand but I really want to get this show on the road. Building the dryblower has worked into a much bigger project than I planned on (no planning really) but I'm well on the way to putting the big bits together now.

 

[Mackka]

Can't wait to see it in action mate as i am sure a lot of others are also.
Cheers
Mackka

 

[nucopia]

Too right !

 

[Moneybox]

The whole job would be a lot quicker and easier if I had a plan to follow - however, any dryblower I've looked at seems to have enough problems that copying one would only repeat problems. I'm trying to make changes as I understand they should be made. The problem is that I'm not experienced in dryblowing for gold but some things they've done on the machines I've seen don't seem to add up. When it breaks or doesn't work they just repair it instead of redesigning it. Of course I might be making some mistakes in changing things but until it runs we'll never know.

I've spent the best part of two days welding and have used a full 4.5kg roll of wire.

That's 9kgs of welding wire since the start of the job and I've got quite a way to go.

With the bellows mounted into the frame I've started on the riffle trays. There are a lot more bits and pieces than I realised looking over a finished machine. I'm glad I didn't quote the build for somebody else .

I'm starting to link the bits together so at least it looks like I'm getting somewhere.

The little Cat is stretched to the limit lifting the bits and pieces so I have the seatbelt on and the blade right on the ground :8

 

[Mackka]

Fantastic

 

[Dewalt]

Amazing stuff, what would you estimate the weight to be at so far ?

Will you be lifting the finished project with what you eventually buy to fill the hopper ? The skids should make it easier to move around on site though.

To have something like that made to your specifications would cost a pretty penny id say.

 

[Goldtalk Leonora]

more opinions...but only because I respect what your doing.
You talk about not following other peoples poor design.....I agree 100% and almost every dryblower out there will fail.
I believe that it is all about how you present the material to your recovery decks. Catching gold is not that hard actually but what stuffs it up for us is the gold nuggets and/or small particles are encased in or have attached to them bits of dirt/clay/snot etc. What this does is change the Specific Gravity and the surface area.....basically, little bits of gold that you "should" be able to catch wind up floating off the end of the decks. This matters because you will be very unlikely to be working rich dirt of 2GPT or higher. If you get 0.5GPT dirt your doing well. This means..to be economic...you have to get all those little bits you can. In turn (and again, it's only my opinion), I believe the key to dry gravity concentration is to scrub the dirt before you present it to the recovery decks. Basically...if you tip your dirt into the hopper and it runs directly out onto the decks then you are loosing gold. How you bash up the dirt is up to you! Hope you don't mind my comments.

 

[Moneybox]

more opinions...but only because I respect what your doing.
You talk about not following other peoples poor design.....I agree 100% and almost every dryblower out there will fail.
I believe that it is all about how you present the material to your recovery decks. Catching gold is not that hard actually but what stuffs it up for us is the gold nuggets and/or small particles are encased in or have attached to them bits of dirt/clay/snot etc. What this does is change the Specific Gravity and the surface area.....basically, little bits of gold that you "should" be able to catch wind up floating off the end of the decks. This matters because you will be very unlikely to be working rich dirt of 2GPT or higher. If you get 0.5GPT dirt your doing well. This means..to be economic...you have to get all those little bits you can. In turn (and again, it's only my opinion), I believe the key to dry gravity concentration is to scrub the dirt before you present it to the recovery decks. Basically...if you tip your dirt into the hopper and it runs directly out onto the decks then you are loosing gold. How you bash up the dirt is up to you! Hope you don't mind my comments.

Your comments are welcome as long as you realize I'm very poor at following where others try to guide me. I have led my life doing what I can a little differently then most sometimes to my detriment but still that's what makes us who we are.

The best thing here is a wet plant. I know the recovery rate is much higher and some of the reason for that is that scrubbing you talk of is much more easily achieved. In our case I think we will just have to accept a considerable loss but put through the tonnage to compensate. We cannot easily run a wet plant because as you know water is hard to come by and the environmental roadblocks are more difficult to negotiate. I'm sure even a dry trommel would make quite a difference but it's another chunk of machinery to build and maintain. Yesterday I had a bloke ask me if I was running a conveyor to dispose of the classifier runoff. I thought, what a good idea but that means another drive, another conveyor belt and another job I'm not ready to start.

Perhaps when I get going I'll learn enough to make those changes but for now I'm aiming for the basics and we'll suck-it and see

 

[Moneybox]

Amazing stuff, what would you estimate the weight to be at so far ?

Will you be lifting the finished project with what you eventually buy to fill the hopper ? The skids should make it easier to move around on site though.

To have something like that made to your specifications would cost a pretty penny id say.

My best estimate of the weight will come from my steel invoices when I get around to adding them up. Then there's a $1000 or more in bearings, conveyor rubber, engine, shafts & gears etc. It's not a heavy machine although all bits add up like all the little things you load into a camper when you're going away that eventually put you over the load limit. My current guess is it'll come in at between 1200 and 1500kg. I'll have a couple of rear wheels under the back of the frame and a tow hitch to get it to site and whenever I need to move it far. The skids will handle all the movement about the minesite. It will never be lifted or moved when loaded with dirt.

The cost? Well it goes up every week. The materials cost cant be printed here because Mrs M sometimes reads what I write The labour cost is showing in my age lines and fatigue level. Hopefully some of that can be reversed when I see the fruits of my labour :lol:

 

[Goldtalk Leonora]

Hi Phil, quite right....no guidance intended...only comments based on my own experience. Your right about wet plants.....great idea in the right circumstance but only when the tonnage is there (water bore) or a convenient mine to de-water is nearby. I believe that scrubbing is critical to any dry plant....one thing I saw on a plant similar to yours appears to be was a heap of chain running top to bottom on the grizzly. The chain was loose and so when the grizzly was shaking so too was the chain....with the idea of it breaking up some of the dirt. I never saw it actually running dirt and so can't comment as to it's effectiveness or not but may be a consideration down the track? I use a trommel scrubber myself so the rocks etc do the work.....material comes out like talcolm powder and the gold has nowhere to hide!

 

[Moneybox]

Hi Phil, quite right....no guidance intended...only comments based on my own experience. Your right about wet plants.....great idea in the right circumstance but only when the tonnage is there (water bore) or a convenient mine to de-water is nearby. I believe that scrubbing is critical to any dry plant....one thing I saw on a plant similar to yours appears to be was a heap of chain running top to bottom on the grizzly. The chain was loose and so when the grizzly was shaking so too was the chain....with the idea of it breaking up some of the dirt. I never saw it actually running dirt and so can't comment as to it's effectiveness or not but may be a consideration down the track? I use a trommel scrubber myself so the rocks etc do the work.....material comes out like talcolm powder and the gold has nowhere to hide!

A very interesting concept. Imagine how many metres of chain you'd need to make it effective.

 

[Nightjar]

MB, Looking forward to seeing the results from your dedicated build. Good luck.
It is a certainly probable that gold will slide off your top screen. We have never operated machine fed dryblowers but spent hundreds of hours with a shovel and at the end of the day we flattened out the oversize piles and run a detector over with the occasional nugget found that didn't fit through the top screen. Nothing escaped the riffle boxes.
Also years back we found an area that had been done over with a large scale dry blower. We bagged up about 50kg out of one of the fines heaps and took it back to the camp and run it through one of our small dry blowers. We were very surprised with the amount of very fine gold we found. We next took our dryblowers out to the area and spent a day there demolishing one of the heaps. One heap gave up an ounce of very fine gold, not a bad days work.
It is obvious the past operators weren't interested in retrieving the fly s**t.
Not interested in teaching an old drake new tricks, however one bit of advice.
Tweak your dryblower before getting serious. Add a number of snips of lead, flattened shotgun pellets will suffice.) to a batch of dirt and put it through, checking after each run to see how many lead pieces were retrieved. When I built my little puffer, was fortunate enough to have access to a lathe and material to machine multiple sized pullies and experiment with ratios to get the ideal puffer speed. Too slow it bogged down, material including fine gold flowed over the top of riffles. Too fast and material including once again fine was thrown over the riffles.
Took time and experimentation but the end result was even mustard gold was retrieved.
Unfortunately time has caught up with my old bones and with much regret I sold my machine a couple years back. Was gobsmacked when a fella rocked up and gave me extra cash from what I was asking. (His Mrs didn't look as happy.)

Anyway, once again MB, your bigger scale end result will create a lot of interest with out any doubt.
Happy New Year to you both.

Peter

 

[Moneybox]

MB, Looking forward to seeing the results from your dedicated build. Good luck.
It is a certainly probable that gold will slide off your top screen. We have never operated machine fed dryblowers but spent hundreds of hours with a shovel and at the end of the day we flattened out the oversize piles and run a detector over with the occasional nugget found that didn't fit through the top screen. Nothing escaped the riffle boxes.
Also years back we found an area that had been done over with a large scale dry blower. We bagged up about 50kg out of one of the fines heaps and took it back to the camp and run it through one of our small dry blowers. We were very surprised with the amount of very fine gold we found. We next took our dryblowers out to the area and spent a day there demolishing one of the heaps. One heap gave up an ounce of very fine gold, not a bad days work.
It is obvious the past operators weren't interested in retrieving the fly s**t.
Not interested in teaching an old drake new tricks, however one bit of advice.
Tweak your dryblower before getting serious. Add a number of snips of lead, flattened shotgun pellets will suffice.) to a batch of dirt and put it through, checking after each run to see how many lead pieces were retrieved. When I built my little puffer, was fortunate enough to have access to a lathe and material to machine multiple sized pullies and experiment with ratios to get the ideal puffer speed. Too slow it bogged down, material including fine gold flowed over the top of riffles. Too fast and material including once again fine was thrown over the riffles.
Took time and experimentation but the end result was even mustard gold was retrieved.
Unfortunately time has caught up with my old bones and with much regret I sold my machine a couple years back. Was gobsmacked when a fella rocked up and gave me extra cash from what I was asking. (His Mrs didn't look as happy.)

Anyway, once again MB, your bigger scale end result will create a lot of interest with out any doubt.
Happy New Year to you both.

Peter

Thanks Peter. Yes I hope we get better results than some of the old dryblowers. Sandra has done well on those piles with the SDC pulling out dozens on tiny nuggets around 0.05g and even up to 0.5g. But on the other hand they were very likely retrieving a lot of one gram and multi gram nuggets that we are unlikely to get. My leases are less than 3km from the Cue caravan park so they've seen a lot of eastern states detectors swinging across them after the local guys had had enough. It surprises me that we can still walk over there and pick up the odd nugget with the 4500 and quite a few with the SDC2300. I think we might detect small patches before loading the top layer into the dryblower that way we should get the few bigger ones that the dryblower would reject. The problem for the metal detector is the old cans and junk that's been left behind in years gone by. They'll even be a problem detecting what falls off the grizzly.

Changing the bellows frequency might be difficult beyond adjusting engine speed but I have made allowances for easily adjusting the bellows stroke. It'll take me time to learn what sort of flow works best. I have a swinging gate at the bottom of the bin. That will constantly shuffle back and forth metering the flow into the riffle trays. I'll be able to easily adjust its travel as well.

 

[Goldtalk Leonora]

Hi Phil, quite right....no guidance intended...only comments based on my own experience. Your right about wet plants.....great idea in the right circumstance but only when the tonnage is there (water bore) or a convenient mine to de-water is nearby. I believe that scrubbing is critical to any dry plant....one thing I saw on a plant similar to yours appears to be was a heap of chain running top to bottom on the grizzly. The chain was loose and so when the grizzly was shaking so too was the chain....with the idea of it breaking up some of the dirt. I never saw it actually running dirt and so can't comment as to it's effectiveness or not but may be a consideration down the track? I use a trommel scrubber myself so the rocks etc do the work.....material comes out like talcolm powder and the gold has nowhere to hide!

A very interesting concept. Imagine how many metres of chain you'd need to make it effective.

no idea...as I said...I never saw it actually work....but chain will cost little if you gain a % return. I run most components electric and so can control just about everything via vfd's. I also run constant and not belows....so gate valves easily control the air running through the decks. I personally believe anything you can do to increase your % return is worth it...also coming down to what machinary your running as fuel is the greatest expense. Getting the small stuff is the bread and butter and what I work on...the days of good size lumps running to overs is long gone...you have to dig deep for those. Your only going to be running the top 200mm or so I would guess...and the good stuff has gone..but the little bits are what will pay the bills.

 

[Nightjar]

Goldtalk, Can't comment on your machine size & capability, but I do know, that the small motorised hand shovel fed bellows dryblowers, beats the constant air feed types hands down.
A rep for a popular "constant air" told me I was talking oop:
When we finally set up a test, the "coldies" he put up front slid down very smoothly.
AND, we kept the couple of grams retrieved with the bellows from their constant air fines at the end of the session. :money: :goldpan:

 

[Moneybox]

Goldtalk, Can't comment on your machine size & capability, but I do know, that the small motorised hand shovel fed bellows dryblowers, beats the constant air feed types hands down.
A rep for a popular "constant air" told me I was talking oop:
When we finally set up a test, the "coldies" he put up front slid down very smoothly.
AND, we kept the couple of grams retrieved with the bellows from their constant air fines at the end of the session. :money: :goldpan:

This is like the old Holden & Ford debate. I spoke to a guy here at our Christmas eve party who mined the Cue area for many years. I reckon he's in his late 70's or early 80's and is still actively mining with a big ball mill and wet plant north of here. He built and operated several large dryblowers over the years swapping between bellows and constant air. I asked him about the difference in retrieval rate. His one word answer was "None"

 

[Moneybox]

I bought some little SS over centre latches to hold my riffle trays down then this morning I thought "How much does it really take to hold that air back"?

I have 800 inches of the riffle tray exposed to the air pressure on each tray. If my bellows were to pump psi then I'd have 400 lbs of lift on each tray
Then there's my poor little Honda lifting each 800 inch bellows, two at a time, so if it were to develop psi then 800lbs of force to lift. I guess the cloth releases most of the pressure when the trays are empty but there must be a fair amount of energy needed to lift that dirt?

All too hard for my little brain to work out so we'll just have to see what happens

 

[Jaros]

Wouldn't the leverage supplied by the lifting cams take care of that weight?

 

[goody2shoes]

Doing a great job there Mr moneybox...

Your wife will not be able to keep you away from it when you have it up and running

 

[Davent]

Im looking forward to seeing it up and running Phil.
Congrats on the win Sandra!