Another Rock Crusher

After a recent prospecting trip I brought home a conglomerate type of rock that I picked up from an area where deep lead mining had taken place. I crushed the rock in my small dolly pot and was blown away to find a few nice little chunky bits of gold in it. I thought this was very interesting as these rocks are everywhere at the old diggings and I figured if it was consistent enough....and I could crush it...then it would pay handsomely.

I set about researching and looking at other rock crushers on the market but on my small budget it meant that I would have to build my own. So when I had a spare few minutes at work I started making it. I decided on the hammer type rotor with fixed blades of steel made out of 40 x 10 mm flat bar instead of the more popular chain type crusher.

The biggest problem I faced was what type of grate to have on the bottom to allow the crushed ore to filter out. The slotted style appealed to me but I thought fabrication of that with narrow enough slots might have been to tricky so I just drilled 2 mm holes in the drum. I countersunk the holes thinking it would act as a funnel to allow the material to better find its way out but after an initial trial I found this only allowed larger rock chips to get caught in the 'funnel' and block the holes. I ended up cutting the drilled section out and fabricating a slotted mesh, the slots measuring about 1.5 -2mm in width. This seems to work fine as it does not clog up and the dirt falls out easy. The only down side is perhaps the crushed dirt is not as fine as you may see on a commercial crusher.




The rocks in question??

the rocks pre crushed ready to go in the crusher

the crushed rock

some little chunky bits of gold

Now after crushing some of these rocks I have found that some have good bits of colour in them and others are completely barren. I have to sample and figure out which ones by appearance have the colour and which ones are worthless. I may end up just crushing the whole bucket load and running the dirt through my dry blower to concentrate it down a bit. Will keep you posted.

Cheers,

Good looking rig mate

Hey MJB

Thats an excellent little crusher you have there.

Its already paid off by producing those bits of colour for you.

I would run every bit of that rock if i were you could be more little goodies inside any one of them.

Great post. keen to see how the rest of it goes.

Darryn

now thats heavy duty great work would like to see pics of the internals of this little beauty

heavy duty alright.....it weighs a tonne :|

After I run the rest of the bucket through I will strip it down again and take some pics of the internals. Its got a fairly tight tolerance on the inside which makes it tricky to set back up again.

I may look at fitting an inspection hatch on the side so I can have quick look in there to see if there are any little nugs jammed in the screen

Cheers

Mate i wouldnt be making any changes to your screening process if your crusher is smashing conglomerates and giving you gold that coarse, i have a 1mm screen on my crusher and all it dose it roll those little nuggies into small easy to loose balls

What's inside these things to do that ??

Here is a pic of the rotor inside..


Basically they are offset pieces of 40x10 flat bar welded to the shaft.

After running the bucket through I will have to inspect it and see if they need to be Hardfaced to make them last longer.

DWT, what type of crusher have you got? I'm interested to see other crushers and how they work so I can maybe make some possible future improvements to mine.

Cheers

Looks mega heavy duty mate! I still would probably prefer a hardened chain setup which can be replaced easily if one broke. Is it possible for you to harden / temper the ends of the flat bar? Get them to a nice yellow using a torch or fire and quench them in some oil. I don't really know if you need improvements unless it is not working as well as you expected, to me it looks like it would be a great beast of a machine to use and reliable

Very nice design , do you have to take it apart to get the crushed Rock out or is there a hole in the bottom

She is a bit big for portability but it dose the job, the large pully drives a primary jaw crusher, and the smaller pulley below it drives the high speed disintigrator, the disintigrator, is basically like looking at the paddle wheel of an old steam paddle boat, it consists of 4 of these type of paddles which is made from 125mm x 10mm plate, the leading edges are all hard faced to stop excess wear, below it is a grate about 200mm in length and 75mm in width, this is made from 6mm solid square bar with 1mm gaps in between each bar, nothing escapes until its been pommeled into next week, the only problem being that gold being soft just gets rolled up into balls or long cylindrical shapes until it gets forced out, i have made different sizes to stop the mistreatment of the precious little blighters but not the time to test it, still havnt got it around home and set it up out the back with a sluice box yet, hopefully within the next month i should be up and running, when i do i'll put a video up on it.

front view whilst running, this is where the 10' plus sluice box will be attached, plus the water will help keep the dust down, "dust dont make old bones"

Hey AtomRat,

I did toy with the idea of the chain style crusher but I figured I would try this type first with the possibility of making the chain one later if needed. I have access to a mig welder with hard facing wire so if the impellors start to wear I can build them up again. The hard facing wire has alot of impact resistance properties making it ideal for this sort of application. Like you say though, if its working fine why change it?

BathurstGold, there is a slotted screen fitted in the bottom of the drum to allow the crushed dirt to fall out. I have fitted another bit of RHS to which a hose can be attached to better direct the dirt into a pan if need be but I just put a 20L bucket under it to catch everything...works a treat but dusty as hell, a dust mask is a must.

Dwt, that is an unreal machine and I bet with those paddles it must make one hell of a racket. I can't wait to see your vid of it in action. Paired with a sluice that would be deadly on gold big and small...great stuff! How does the jaw crusher work?

Cheers

standard cam shaft style jaw crusher mate

Bloody awesome build MJB have you tried running her off a geni yet? i reckon you could do some damage in the field with that baby.

Thanks Goldigg@,

I don't have a geni but yeah your right, its small enough to throw in the back of a ute...not my little Hyundai though :8

I pre crushed the rest of my 20 L bucket last night to a size that can easily feed into the crusher and that was hard enough. I think in the field I would need a larger Dolly pot and 6' crow bar to break the bigger bits up a bit first.

On the other hand, DWT's crusher with the jaw crusher and then the normal crusher would be the bomb! I'm drawing the line though, I'm not building a jaw crusher...where do i stop

I will be crushing the bucket on the weekend, dryblowing it and then panning off the concentrates. I might do a little vid of it all in action.

Cheers

MJB said:

I'm drawing the line though, I'm not building a jaw crusher...where do i stop

Click to expand...

When it comes to Au, one should never stop, dont be shy MJB, hook in!!! :lol:

There is a "Thing" called a "Trailer".
There is another "Thing" called, "I can Do This"
So simple but a thing called a "Genie" could be involved here. LOL and PMSL
Go for it mate. If I had half the inclanation to get the job done.
Just do it...

dwt said:

She is a bit big for portability but it dose the job, the large pully drives a primary jaw crusher, and the smaller pulley below it drives the high speed disintigrator, the disintigrator, is basically like looking at the paddle wheel of an old steam paddle boat, it consists of 4 of these type of paddles which is made from 125mm x 10mm plate, the leading edges are all hard faced to stop excess wear, below it is a grate about 200mm in length and 75mm in width, this is made from 6mm solid square bar with 1mm gaps in between each bar, nothing escapes until its been pommeled into next week, the only problem being that gold being soft just gets rolled up into balls or long cylindrical shapes until it gets forced out, i have made different sizes to stop the mistreatment of the precious little blighters but not the time to test it, still havnt got it around home and set it up out the back with a sluice box yet, hopefully within the next month i should be up and running, when i do i'll put a video up on it.
https://www.prospectingaustralia.co...1411964691_sat_5_april_2014_005-optimized.jpg
front view whilst running, this is where the 10' plus sluice box will be attached, plus the water will help keep the dust down, "dust dont make old bones"
https://www.prospectingaustralia.co...1411964691_sat_5_april_2014_012-optimized.jpg

Click to expand...

All your ideas are valid Tathradj, maybe once I have sourced a bit of colour to help fund a genie I will look into it further. First, I need a new car capable for the job, my 97' Hyundai Lantra just aint up to it and then I will needone of them trailer thingies you talk bout to tow behind said upgraded car and then....where do I stop

I need to get SWAMBO on board first...maybe that's where it stops.

DWT, maybe if I can find some plans for a jaw crusher I will give it a go.

Cheers

Looks awesome MJB! i Dont think i have seen another with that 40x10 arangement for a small crusher

Dan84

heres mine i thorght i would share i am replaceing the hammers