635 replies to this topic

[Pyrogeorge]

i glue inner tube on the roller and now is better but the jar do some "shakes"
maybe i will put inner tube to the jar too..

Now is better

It's easy not to spill anything when the drum is empty! When the drum is full and has 12 hours to run it's almost impossible to go long without a dust of something showing.

If and when the mill jar wears out and the contents spill on the motor.......

Arthur i will mill for 1 hour max time..I make very fast BP in this time so why to run the mill for 12 hours?
Also i made airfloat charcoal in 20min.
The mill is very efficient and i am very happy

[Pyrogeorge]

My Ball mill in action

[E-tech]

http://books.google....d Uses#PPA95,M1

Interesting book:
"The History of Grinding"
Has a lot on evolution of the science of reducing materials to powders.
No specifics, but the general info may help come up with better/more economical ways of milling whatever you
happen to have.

[Pretty green flames]

I have a question, maybe a tad weird one but anyway. Does anyone have any experience with wooden ball mill barrels, this seems like a pretty good idea as a hexagonal shape is pretty easy to make and is more efficient than a standard round one. The thing i'm interested in is how the barrel would hold up to a couple kilos of lead tumbling inside.

[phildunford]

I have a question, maybe a tad weird one but anyway. Does anyone have any experience with wooden ball mill barrels, this seems like a pretty good idea as a hexagonal shape is pretty easy to make and is more efficient than a standard round one. The thing i'm interested in is how the barrel would hold up to a couple kilos of lead tumbling inside.

Don't have my books with me at the moment, but I'm pretty sure Shimizu mentions wooden barrels in lancaster's book.

I would think if well constructed (maybe out of a hardwood) such a barrel would stand up pretty well. I'm guessing the wood would bruise a bit, but then be pretty tough, especially if the outside was held together metal rings.

[Arthur Brown]

If you are attempting a mill with typical dimensions a kilo of lead will mill about 50g of compound! So for a large mill look at 50Kg of lead or more.

While there may be satisfaction in deep DIY there may be value in buying a second user plastic drum. -see Cooperman's big mill drum jars. However 10 kilos of lead balls would just sit in the bottom od one that big, you really would need a reasonable amount of media to start milling. (Then you wouldn't want to lift the mill jar off the rollers)

[digger]

If you are attempting a mill with typical dimensions a kilo of lead will mill about 50g of compound! So for a large mill look at 50Kg of lead or more.

While there may be satisfaction in deep DIY there may be value in buying a second user plastic drum. -see Cooperman's big mill drum jars. However 10 kilos of lead balls would just sit in the bottom od one that big, you really would need a reasonable amount of media to start milling. (Then you wouldn't want to lift the mill jar off the rollers)

Ceramic is a must for large jars, still not light but far easier on the back than lead.

[cooperman435]

I'm a purist though and still would try to use lead simply as the weight actually does the work faster and better surely?

[digger]

I'm a purist though and still would try to use lead simply as the weight actually does the work faster and better surely?

I agree you can argue that. However I have tried both and I have not seen a significant difference in milling times. Lead is much softer so the impulse energy of ceramic may even be higher due to its unyielding surface.

There are some arguments on lead contamination of BP too, but that is for someone else to debate.

If you have a large milling jar say 400mm in diameter and 300mm wide the you would need around 150Kg of spheres to half fill it, that is crane territory.

[Arthur Brown]

For safety when lifting 10 kilos is reasonable and 25 kilos is definitely too heavy to handle manually safely. Remember that you would need to pick the drum up and tip it into a stack of sieves even just to separate the balls from the product.

Trying to work on a firing site with a bad back due to bad lifting rather takes the fun out of fireworks!

[cooperman435]

Arthur ya should come see me at work!

2 weeks ago I was re plastering a 4th story bedroom and I reckon it was close to 1/2 of a ton of stuff uphill and about the same to drag out too :-( 35kg is standard unfortunately for me

Thats not even starting on last weeks 105kg shower tray or the 234kg steel beam we put in the same house (though admittedly I had help with those)

Edited by cooperman435, 25 February 2009 - 12:24 AM.

[captainuk]

My ballmill is made out of a toilet cistern float that screws on to an winscreen motor and runs from a 12volt power supply you only need about 6 or 8 balls in and it does the job well i put it on when i go to work when i came home job done it has a long lead so its out in the garden for safety i would put up a photo but cant work out how you do that its asking for a url?

Edited by captainuk, 19 May 2009 - 10:35 PM.

[Mortartube]

The Spanish use wooden ball mills. In fact if you saw the programme on TV a couple of years ago, where a concrete full sized parliament was made (of Guy Fawkes' day) and they blew it apart. their powder was made in wooden barrels that rotated and they had large hardwood wooden balls inside, like the type found on top of a newel post on a stair bannister.

I believe they were powered from a water wheel.

More commonly though, edge runner mills are used like this in large scale production.

http://wpcontent.ans...l_Equipment.jpg


http://www.youtube.c...feature=related

If you watch the above from 3.35 you will see the barrels used to mill BP.

Edited by Mortartube, 20 May 2009 - 12:09 AM.

[Arthur Brown]

Perhaps we could have Richard Hammond and Sydney Alford to be guest speakers at the next AGM please.

[Greenman]

People. Today i have been so fortunate of succeeding a planetary ballmill from my job. They were going to trash it, and asked if anyone had use of it. The problem was that only two of the four jars worked, and it had malfuctional closing lid so it was very noisy.
From what i have tried, it is incredibly faster at milling jobs, than my older mill! I tried my first batch today and i did a perfect milled tigertail comp. after 30min of milling. Has anyone any experience with these mills, or by any chance owing one? I was just wondering how safe it was to mill BP for example? The TT batch seemed to work wonders.

I understand that private people owning planetary mills are few, because of their excessively high price.