Home sampling finally started

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The crusher sold by Reeds is pretty much a direct copy of my mill which was made by Johnoela Engineering in FNQ some 30 years ago. A very good design which is still going strong.
 
The bearing has a bit of play in it now and I can't find my grease gun either (packed in one of the many boxes and crates in the shed) but I fixed the handle coming loose issue by putting a washer and thick O ring between the handle and mounting bracket, fired it up and seems to be running ok but I suspect the bearing needs grease now so won't crush anymore until l buy another GG tomorrow.

On the up side, the CC packed it in when I was crushing a sample of host rock/quartz I'd just reduced in the dolly, I got the sample yesterday while out looking at a creek (I was meant to be working) that was flowing to hard to sample pan, I drove around for a bit then noticed a spot in the bush that looked like a depression in the hill side, it was an old working and a quick walk up I noticed there were several quartz leads still in the vertical crevices but it looked as though the main reef had been dug out long ago.
I grabbed a fist sized sample of host rock with quartz attached that was just laying on the ground and ran it through the dolly when I got home and decided to fire up the CC, that's when things turned for the worse.
I had a hunch on this spot so I put my rock sampling gear in the van this morning and went to my first job the "long" way and got 10ltrs of soil, quartz and host rock from in and under several of the crevices.
When I got home today I put the partly crushed sample from yesterday through a fine kitchen sieve so I could pan the dust and put the rest (90%) aside for when the CC is good again.
Result from about 3/4 cup of dust = 5 small specs that I could get with the tweezers :D
Keen to crush the rest now and see what's in the bulk of the first sample, then put the 10ltrs aside (labelled) with all the other buckets for when I get the shed sorted.
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Ah no, it is the speed needed to keep the quartz suspended and the crusher to work effectively. I am talking tip speed not rpm. If you slow down the machine the particle size of the quartz discharge increases. It also stops the machine bogging if the inlet feed is too big. I am talking production not sampling with the discharge fine enough to go over a table.
 
Hi Bill
It is clear you did not read the link

With 25 inch blade at 3600 rpm would have a tip speed of 19000 ft per minute,but at at 3400 ft "SEC" you would have 204000 RPM, impossible
I would not like to be any near it.

I have worked around machine to long,and at quarries.

From old Sparky

Frank
 
Puddler Bill said:
The crusher sold by Reeds is pretty much a direct copy of my mill which was made by Johnoela Engineering in FNQ some 30 years ago. A very good design which is still going strong.

Yeh looks a very good design PB, and a nice principle for tertiary crushing units i reckon.

I dont own one as such because im more of a loam sample taker and generally dont crush random rocks to sample until i get to the costean/sinking stage of a deposit where its important to mill all samples 'going down' for best results.

Have been working an area for the past year or so now and my results show im getting very close to where i think this deposit may be, so I may need a decent crusher to develop into the next stage of sampling and then hopefully some ore refinement.

As a maintenance supervisor in the quarry industry for a short time, I have had experience with the larger VSI units in tertiary, but not with the smaller sampling type mills.
Our Primary was a jaw, secondary a cone.

How do you find the VSI for your crushing needs on a smaller scale?

Any experience you can share with me on them as compared to other mills, would be fantastic mate.

Thanks and Cheers ;)
 
oops, my mistake, I meant 3400rpm.

I run my mills a little faster than big mills run as I do not use a ball or rod mill to finish the crushing and grinding stage.
 
New grease gun and grinder realignment with handle issue fixed = CC now running better than ever.
Crushed the rest of that first sample (20 something scoops) = no more gold.
This tells me that the 5 pieces of gold from the first lot of powder had separated in the dolly pot since I only CC'd about 6 of 30 scoops yesterday, then panned it out along with the powder from the dolly.
That's interesting to know and surprising at the same time.
 
Good to hear you got her aligned Pete... thats a shitter about the dolly.. ive fallen for that trap many a time but i never want to wet my dolly when im sampling and never remember to wash it after a sample
 
I've done similar too, contaminated my samples and then wondered where my gold came from. Silly thing though, I still do it and haven't learnt :D
 
I must have worded it wrong.
I initially crushed the first sample in the dolly, dolly was pretty clean as nothing prior has shown colour and no visible material in the bottom before I started, then put all crushed material into one pan, then I ran 6 half scoops from that into the CC and put the powder aside. When the CC decided on a smoke break I decided to sieve all the sample so I could pan out the powder from both at least while putting the rest aside again. The host rock was slightly damp when I dollied and softer than the quartz, it compacted in the bottom of the dolly and I had to scrape the bottom to loosen the powder up.
The 5 specs came from the initial dolly crush on this sample, I noticed in the loupe it was rough and thought it was odd thinking it had come through the CC, after crushing the rest of the sample tonight for no colour I think the gold had released from the host rock in the dolly...........if that makes sense?
 
I might experiment with the other 10ltrs, try and dolly right down v's the CC, you've given me something to think about now.
 
Hi Bill
Nothing to worry about,everybody gets those "oops"moments.
Enjoy reading you post,you have a lot to offer in experience,so keep at it.

Regards Frank
 
All good Frank. My first seniors moment. I do find that with the hammer mill the gold does not grind fine. In fact it rolls up into small balls and drops through the screen. Keeps the gold coarse while the quartz is fine.
 

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