GGs Chain Flail Impact Mill

Thanks for the suggestion on the vortex mat. I have an extra 3 foot long sluice that can be used as a dedicated sluice for the powdered ore. It has an old red felt like type of material currently for the matting, about 2 feet long under the riffles. Should I run the vortex mat the whole length? Or use the header portion as the "slick plate"? I do appreciate everybody's suggestions and comments on this build. Having somebody actually build one and work out all the kinks, then post all that information, eliminates a lot of guess work and having to experiment. Can't wait to get the rest of the build material for the drum!

I would recommend slick plate and then vortex mat the whole length. Best to have the slick plate level with the top edge of the mat. You don't want any slurry going underneath the mat! and NO riffles.

GG~
 

Good forum post, interesting crusher. I too am sick of the 'one stamp mill' when prospecting. Why dont you come and sample run samples on my mine claims?

Seriously though, how long can your crusher operate, can you see it as a full time one man band mining operation or just sampling for an hour or so a week?
 

Good forum post, interesting crusher. I too am sick of the 'one stamp mill' when prospecting. Why dont you come and sample run samples on my mine claims?

Seriously though, how long can your crusher operate, can you see it as a full time one man band mining operation or just sampling for an hour or so a week?

Not recommended for constant use day in and day out due to requiring chain replacement on a regular basis.

For full time milling I would suggest a homemade ball mill instead due to less maintenance and much cheaper to operate in the long run. Although a ball mill is not as fast as the chain flail it would be better as a constant use method.

GG~
 

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I was wondering if you builders were balancing the shaft systems you created ? The other imput I would have is to try and find or buy some used log skidder chains , you can get them with up to 3/4" links and they won't have as much wear on the outside loops and they are the hardest chain I know of , you can take what you want and scrap the rest for a good price . The other things I've been thinking about were maybe adding a couple of small blower fins , and some bolt in wear plates using a counter sunk bolt like on a dozer blade . I sure that some company make small hardend bolt ,Fasinal would be my guess . After seeing your builds [ great job by the way ! ] I'm think of using a cart like off of an old generator , or something similar with a couple of ramp and maybe a nylon strap come along for loading it . This is definatly a great thread , please keep the pictures coming as well as more material ideas .
 

I have been trying several different chain set ups , the best I have came up with is cutting 1"x 1.5" cutting edges from any ground engagement blades ( cutting edges ) welded on each chain end , I built a 16" crusher , workers and last four hours , constant usage , depending on the hardness and size of rock , I crush quarts 3" and hard end rhyolite mostly . Very hard , now getting a bought 4-6 hours and I'm happy ,

Made two chain sets with iron between two chains like a swing . Kills the engine .
 

Not recommended for constant use day in and day out due to requiring chain replacement on a regular basis.

For full time milling I would suggest a homemade ball mill instead due to less maintenance and much cheaper to operate in the long run. Although a ball mill is not as fast as the chain flail it would be better as a constant use method.

GG~

I currently have a 2t / hour ball mill and 2 1450 5 stamp mills, I was just looking for something for more of a prospecting role that is portable. 3-4 hours per day.
 

That is exactly why I built my crusher , move and test at a fairly reasonable rate . Mounted to my trailer on the front , I carry 40 gallons of water in trailer in 5 gallon water cans , and rest of equipment I think I would need , not sure how to add pictures or I would send you a pix .
 

ImageUploadedByTreasureNet.com1452132615.220764.jpgImageUploadedByTreasureNet.com1452132647.200493.jpg
 

Great thread, guys. Wish I had the fab experience and skills to do builds like this. Very nice work.
I'll try to describe my setup and maybe post some pics later.
Mine is setup to run at home. Runs by 1.5 hp 220V elec motor with pulleys and belt at about 3000 rpm to the shaft. I believe tip speed on the chains is about 70 mph. It could be run in the field with a genny, but I enjoy scrounging ore afield and milling on occasion at home. The neighbors think I'm nuts, of course, and that's part of the fun. :laughing7:

I have the same crusher as in post #8. I believe the guy that made it is Richard Hansen.
It's a smaller unit, about a 8" drum. Mine doesn't have the welded chute added onto the output like in the photo. That output corridor (arm) is unique on these little chain flails and seems to work well - ends up being a wind tunnel on the output. I have a 10 mesh stainless screen on my output which feeds a 1 1/2" clear flexible hose (spa hose). That hose is routed directly into a 15 gallon enclosed tub that has a vent port outlet on one side with a long length of vacuum hose that is hooked up to a small shop vac. Obviously, I run the shop vac while crushing. With this setup, there is virtually no dust in my milling area (outside). The shop vac is venting fine dust some 30 feet away. I still wear a dust mask and eye and hearing protection.
My particular chain flail uses two separate lengths of chain in loops, not as single strands as is more common. The bottom link of the loop is the only one that will get worn and it is providing a good sweep as it rotates. Of course, the chains can be flipped for longer wear, but I had a welder add on what Jair recommended above… that is, cut-to-fit pieces of hardened steel cutting blades on the two striking faces. This works very well and the wear seems to be moderate. So far, I have only milled 200 lbs of material on each side of the links and it looks like the faces will take several hundred lbs more before needing replacement. Before, I was using the mill without the cutting blades and wear on the links was problematic.
The other thing I'm doing differently than before is I'm using a small 3"x4" jaw crusher (Golden Manf. Merlin, Or) as a primary. This knocks everything down to 1/4" minus and not only allows a more steady feed rate into the impact mill, but greatly reduces the wear on the chain flails (or hammers). The problem is that inexpensive jaw crushers are hard to come by and usually aren't portable. They are fantastic tools for crushing, though.
I believe someone wanted to know whether the chain flails need to be balanced. I'm experiencing excessive vibration while using my impact mill. I believe this is due to the custom work I had done on the flails. I need to unbolt the flails and weigh each one. Then, I'll have the welder get the weight balance of them closer. I had to put 100 pounds of weight on my stand to keep the whole thing from wanting to scoot. That extra vibration probably helps with output, but will certainly kill the bearings prematurely.

Overall, I'm happy with this setup. Milling and recovery of values from hard rock is not something I thought I'd get into, but after enough years of small-scale placer mining, it just seemed to happen naturally. I can't say I'll be doing a whole lot of it, but it's something different to experiment with between placer mining.
Personally, I wouldn't bother milling and processing anything on a micro-scale like this unless gold values were at least a couple oz/t. Most of the ore I have milled produces gold in the 100 minus mesh size. This is a pita, but the values are extremely high, so it's worth the effort.
Screening the milled ore by hand is the worst part. I screen to four fractions using 30, 50 and 100 mesh screens. 30 mesh plus gets a fast panning. 30-50, 50-100, and 100 minus gets run through two simple cleanup sluices fed with small, vibratory feeder. Sluices are just regular ribbed mat in the first, and California sluice (his business is for sale) drop riffle in the second, using 750 gph 12 volt recirc pump. 85% of the 100 minus gold is captured on the first run. The larger fractions, of course, behave a little better.
Whole setup probably cost about $1,500. I run both crushers off the same elec motor.
Light snow falling outside, so thought this would be something worth sharing.
Happy crushing. :thumbsup:
 

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I thank you for sharing , and glade you were able to make your chains last longer also . That was my frustrations , changing chains so often . Now they last a lot longer . Well worth the time to fab and test .
 

my prospecting buddy from work is going to get the materials to build one of theses in the coming weekends. thanks for posting this helps me a lot in deciding what and how to build what I want.:thumbsup:
 

I thank you for sharing , and glade you were able to make your chains last longer also . That was my frustrations , changing chains so often . Now they last a lot longer . Well worth the time to fab and test .

I'm in the initial stages of building a chain crusher too. I'm making the crushing chamber out of 10" flat bar, 3/8" thick, welded into an octagon with 1/4" plate back and front plates.

It'll give me a 24" high crushing chamber. The one thing I'm going to do to decrease wear on the chains is make chamber 12" deep. I figure there are more chains to spread out the impacts per link. Going with a 16 hp gas motor with a 3" to 5" reducing pulleys. It'll mount on a 2" square tubing stand. She'll be heavy as all get out, but should be able to handle 4" rock.

Some of the ore we've found.

lode 1.jpg

lode 2.jpg

lode 3.jpg

Kind of off subject with respect to crushing, I've been told that dirty looking quartz like that is what I should be after. Something along the lines of what a bbq'ed chicken should look like if its been coated with barbeque sauce prior to cooking. That sound about right to y'all?
 

Kind of off subject with respect to crushing, I've been told that dirty looking quartz like that is what I should be after. Something along the lines of what a bbq'ed chicken should look like if its been coated with barbeque sauce prior to cooking. That sound about right to y'all?



Rotten/decomposed/stained quartz is a good indicator and crushing will tell the rest of the story. Not all rotten quartz contains gold but it's worth a try because when the iron staining (gossan) appears it's a good indicator.

Of course visible gold is THE best indicator but in lieu of that you have to follow your best clues.

I would suggest you do a google search on "Gossan"
Gossan is rust produced from sulfide minerals that sometimes contain gold and silver.

When it comes to hardrocking, remember the old saying that: "gold wears an iron hat"


Go for the Gold
GG~
 

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Rotten/decomposed/stained quartz is a good indicator and crushing will tell the rest of the story. Not all rotten quartz contains gold but it's worth a try because when the iron staining (gossan) appears it's a good indicator.

Of course visible gold is THE best indicator but in lieu of that you have to follow your best clues.

I would suggest you do a google search on "Gossan"
Gossan is rust produced from sulfide minerals that sometimes contain gold and silver.

When it comes to hardrocking, remember the old saying that: "gold wears an iron hat"


Go for the Gold
GG~

I've done a little bit of reading up on mineralogy and have familiarized myself with gossans and their precious metals content. The next step in my education is getting the crusher running so I can better judge what looked good in the field versus what looks good in the pan.
 

I've done a little bit of reading up on mineralogy and have familiarized myself with gossans and their precious metals content. The next step in my education is getting the crusher running so I can better judge what looked good in the field versus what looks good in the pan.

Did you get your crusher running yet?
 

Hey Goodyguy, how is that impact mill design working out for you? I was looking at the layout of the base you built and was curious to know if you would of changed anything
 

Did you get your crusher running yet?

Oh yeah. Did some redesign of the flange bearing layout and it runs dang good. Waiting on my welding machine to come in so I can do some more changes with it.

I've got two samples crushed, sitting in buckets outside on my patio. I haven't done any pan testing on either, yet.
 

Hey Goodyguy, how is that impact mill design working out for you? I was looking at the layout of the base you built and was curious to know if you would of changed anything

I can always think of things that I would change or tweak but the overall layout of the base seems to work fine as is. What are your thoughts of changing?

The only thing that really needed to be changed on my prototype design was the discharge port. Needed to drop it straight down from the drum instead of at a 90 degree angle. Other than that I was satisfied with the build.

Did you see how jair addressed the discharge port issue on his build later in the thread?


GG~
 

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