2 flails versus four?

[SaltwaterServr]

I had a flail crusher drop into my lap this weekend for a price I couldn't pass up. I got to thinking as I'm planning some mods to it, why don't folks run 4 flails instead of just two? You'll get twice as much life on your chains and if you have a double digit hp motor, it should put out enough torque.

One of the reasons I can see is starting the engine without an idle pulley on it would be tough. Second you'd most likely need twin belt pulleys too. A little weight difference but considering the weight already, 10-12 extra pounds is worth double the time between chain switch outs.

Any thoughts on it?

 

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[kcm]

One thing to consider is how long the chains are. You don't want to have chains that can possibly hit each other after deflecting from a rock. This could cause undue wear on the chains.

Some units use bars or rods instead of chain. As long as the bars/rods were mounted offset, I think it would work fine. By offset, I mean to have 2 bars, then move over a couple inches and have another two bars. they could be mounted next to the first set or offset 90°.

I have no experience with those type units, but you asked for thoughts.

 

[desert-rat]

Mine has two teeth off a back hoe bucket and about 8 chains per side. its pretty heavy to get started but not bad. if you over load it and kill the motor you have to take the drum apart and clean it out to start it which is a pain and a major no no after you have done it a time or two. The chains wear way to fast to be profitable to used for sampling. I bought the best 3/8" chain I could find and it still doesn't run but about 750-1000 lbs of ore before its shot. im probably going to make a blower hook up to help it clean out that seems to help a lot from what little ive played with it. if I can get my hands one some sort of hardened material I will attach it to the end of my chains to improve life span. I even tried using running water with the material to make it dustless which worked but took way to much water and was pretty messy. my output port is just slits cut with the thinnest cut off wheel I could find and my material comes out from -100 to -150 with about 10% of it being 50+. I may add a port to give it the ability to process more material as I think this is the biggest thing slowing me down. hope this helps

 

[bobw53]

I've been thinking about this... And the biggest reason I can think of is the KISS principal... 2 sets of chains off of a shaft is relatively easy to do... 4 sets
and you are adding parts and complexity.

As for reducing wear on the chains.. I'm curious on that one... I guess it would depend on how and why the chains wear out.. Each chain may get less BIG impacts,
but each chain is still swinging around through an abrasive fog of crushed rock.. I think life would increase, but I don't think it would double..

Be an interesting experiment... Chain life of 2 sets vs 4 sets...

 

[Goodyguy]

I assume you meant 2 chains on each side of the shaft vs 4 on each side?

Flail units with 8 total chains are twice as wide, will work with larger or more ore at a time but require a larger engine with more HP and the chains wear out accordingly.

The main reason for going with an 8 chain unit over a 4 chain unit is to process ore faster.

Mine is a 4 chain flail (two on each side) and will take ore up to 4" diameter.





GG~

 

[bobw53]

I assume you meant 2 chains on each side of the shaft vs 4 on each side?

I know what I was talking about... But I went back and read again, and I'm not sure we are all talking about the same thing...

What I thought we were talking about is adding extra sets of chains... What you have there (and its a purty one) I would consider 2 sets, even if you double the
width and go with 4 chains wide, I'd consider that 2 sets.. I thought we were talking about adding in two more rows(sets), so the chains were 90 degrees apart instead
of 180 degrees.

 

[kcm]

I was under the impression that BOTH additions were being discussed, as there was never any specifics mentioned.

 

[Goodyguy]

I know what I was talking about... But I went back and read again, and I'm not sure we are all talking about the same thing...

What I thought we were talking about is adding extra sets of chains... What you have there (and its a purty one) I would consider 2 sets, even if you double the
width and go with 4 chains wide, I'd consider that 2 sets.. I thought we were talking about adding in two more rows(sets), so the chains were 90 degrees apart instead
of 180 degrees.

Ohhh Now I get it. Sorry for the misunderstanding.
You did not mean go wider, but in between. Hmmm never seen one with that configuration before, be interesting to see the results.
One thing for sure it would be more balanced.




As far as needing an idler pulley goes. Mine starts easily with one or two pulls because there really isn't that much drag as the drum is empty when you start out and the shaft holding the chain is on ball bearings.

GG~

 

[jair]

I think you would need a larger engine , more chains means more contact not giving the engine any brake at all .
But could do a faster brake down on the material ,
I'm sure you would only be able to crush 1-1.5 " hard rock and need more chains on hand when replacing the chained , they may last longer ,

 

[SaltwaterServr]

Ohhh Now I get it. Sorry for the misunderstanding.
You did not mean go wider, but in between. Hmmm never seen one with that configuration before, be interesting to see the results.
One thing for sure it would be more balanced.


View attachment 1321464

As far as needing an idler pulley goes. Mine starts easily with one or two pulls because there really isn't that much drag as the drum is empty when you start out and the shaft holding the chain is on ball bearings.

GG~

That's exactly the configuration I was thinking of, chains at 90° to each other. The one I bought has 3 sets per side offset at 180° right now. My engine is 11hp, but if my mining partner can't rebuild it, I'm going to go up to a 13 or 16hp.

I've got a continuous feed ball mill to build in my near future too. Probably this coming winter.

 

[kcm]

If I may suggest, try going with an even larger size engine. One reason is that it won't bog down. Another is you can set it up with pulleys that allow the engine to run at a lower speed while supplying the same horsepower. And last, a larger engine can better handle the blows and vibration of the job. As for expense, you can always buy a low-end riding mower and have new parts left over for other jobs.

 

[SaltwaterServr]

If I may suggest, try going with an even larger size engine. One reason is that it won't bog down. Another is you can set it up with pulleys that allow the engine to run at a lower speed while supplying the same horsepower. And last, a larger engine can better handle the blows and vibration of the job. As for expense, you can always buy a low-end riding mower and have new parts left over for other jobs.

This papoose here might fit the bill for $300.00

DuroMax 18 Hp 1'' Shaft, Recoil Start Engine

I wonder if getting a length of 500B abrasion resistant flat bar in 1/2" thickness and building hammers in place of the chains would give a better service life? The contra of course is having to cut the hammers to length and drilling the mount hole. Might be less hassle to just go with more chains.

 

[kcm]

This papoose here might fit the bill for $300.00

DuroMax 18 Hp 1'' Shaft, Recoil Start Engine

I wonder if getting a length of 500B abrasion resistant flat bar in 1/2" thickness and building hammers in place of the chains would give a better service life? The contra of course is having to cut the hammers to length and drilling the mount hole. Might be less hassle to just go with more chains.

From what I've read, the DuraMax products seem to either work or they don't. That's the brand water pump I bought - the pump is faulty, but the engine ran like a charm! Then suddenly, without warning, the engine stopped working. Haven't tried to get it running again since, so it "may" still work. But lots of reviews seem to suggest that it's not uncommon for a unit of theirs to not work. ...But then that's the Mead in China approach. They save money because they have little if any quality control. Therefore, everything is disposable. When all good parts come together, it's a great product. However.........

 

[SaltwaterServr]

From what I've read, the DuraMax products seem to either work or they don't. That's the brand water pump I bought - the pump is faulty, but the engine ran like a charm! Then suddenly, without warning, the engine stopped working. Haven't tried to get it running again since, so it "may" still work. But lots of reviews seem to suggest that it's not uncommon for a unit of theirs to not work. ...But then that's the Mead in China approach. They save money because they have little if any quality control. Therefore, everything is disposable. When all good parts come together, it's a great product. However.........

About like anything bought from China, consider it immediately disposable and compare it to American made prices/quality. For what you'd spend on a Honda or Briggs and Stratton, you can get three of those DuroMax's.

I forgot that this Australian fellow had his crusher set up as a hammer mill with four hammers. He says he gets around 2000-3000#'s of rock run before the hammers wear out. He shows the hammers pretty much close up in the first minute or so.