Ball Mill Project

Wow so you mean EXACTLY 0.5 HP seems a bit extreme given the difference would cost a whopping 2 pence an hour

So how about this one....

http://www.ebay.co.u...c4#ht_613wt_952

lol it was just my opinion, you dont have to take it at face value, although they do suck up juice under load, heres a 1/4 hp mill i made, i changed the motor for a 1/2 hp as it ran hot, and would stall on start up

Edited by dr thrust, 28 June 2012 - 09:44 PM.

Wow so you mean EXACTLY 0.5 HP seems a bit extreme given the difference would cost a whopping 2 pence an hour

So how about this one....

http://www.ebay.co.u...c4#ht_613wt_952

Just to throw another idea in to the mix, I made this for my lad for Christmas for polishing stones, it's running a 12v motor that has a reduction gearbox built in, the motor costs less than a tenner and will turn over 2kg total weight.



I also got him a solar panel from Maplins for £20 that tops up the leisure battery that runs it so effectively it costs nothing to run!

Ha! I'm loving the idea of running one eternally by solar power. Nice work!

I think I will go for the more powerful of the motors I saw. There is nothing in the price and I'm not concerned about the additional 2 pence an hour. I'm really not going to be running it that much and it's mainly to make small amounts of BP which is good enough for lift and break. I also like the idea that it won't be too heavily loaded and will run cooler.

All my other chemicals are either bought at the right mesh or I grind in coffee grinders until they are fine enough.

To throw another spanner in the works and make your choice even harder, you might consider an inverter and 3 phase motor setup.
The second hand equivalent of this can be had for around £50 - £60 if you are patient on ebay. (I know of someone who bought a local 3 phase motor for 99p! and a 2.2 Kw inverter for about £50)
The benefit of this setup is virtually infinitely variable speed control and its very easy to implement start, stop, reverse, jog, and speed control via a light duty cable remote control.
No buggering about with gears or pulleys, no loss of power.
If you think carefully about how you design and build the mill you can use the same bits to drive a star roller when you discover you want one of those.

Arghhhhhhh

OK last try and getting a consensus of advice. It seems people don't all the threads before posting so let me summarise again.

• I only want to build a small mill.
• I don't mind paying for good quality components.
• I will only be doing the occasional run of small amounts of around 100g.
• I would prefer it to be quick and efficient as I don't want to leave it unattended.
• I buy almost everything else I need pre-milled.
• I've got a 3 litre jar with 1kg of ceramic media so far.
• I've ordered 20mm rollers and pillow block bearings.

I just need advice on what motor to buy. I think single phase for now would be fine and I will gear it accordingly.

Is 0.5 HP exactly what I need or is this really for people doing larger amounts of milling? I don't want it to get hot if it's being thrashed etc etc so if larger is safer then I'm all up for that.

If I can do this on the smallest motor I mentioned previously then great, I'll order that one.

ceramic media?!!!!!, haven't you seen the "ball mill explosion" threads, id rather put my D@~k in a mouse trap, lead or brass for bp, milling efficiency will be a product of correct speed, correct media size for your jar size and how full you charge the jar its all there on the ball milling thread.
but realistically there's no quick fix these things are left to run for a few hours at least, i have a simple household timer on mine the sort of thing you'd have for switching on lights/lamps if you where away, that way i don't have to sit on the thing all the time and get constant results which is essential in my bp rocket propellants, i may need 3hour bp not 3 and 3/4 hour bp lol.

so to round up, this is my experience of the matter and ive been milling for five years now.
for small amounts( 100g) lots of people use rock tumblers, i myself used one for a year or so with 12.5mm round brass bar media in a one liter jar with good results.
next i decided to make myself a mill, luckily i found a pillar drill at a car boot and used the components of that, the motor was of a cheap chinese construction as the whole pillar drill would of been worth £60-70 new, it was rated at 300 watts, i found this struggled at bit and got hot with lead media, properly because in was a cheapo motor not enough to burst into flame though lol.
the motors your looking at are better quality and as with all "continuously rated" they have a cooling fan blade system built into the rear of the motor housing as these things are designed to run non stop.
sometimes if there's not much airflow around the motor people add computer cooling fans nearby.
the motor choice may be up to you and your media you'd get away with the smaller motor with brass media, but not lead, maybe you secretly want a 0.7 hp motor? its pretty powerful you can use them to run small lathes like the myford, one thing though if you did decide to build a bigger mill, and this usually happens 9 times out of ten, you've got the motor for it

I know this has been covered before,but as long as you use the correct ceramic media,(ie,cyclebs)which are made for the job then they are perfectly safe, (as can be).

I believe that Gareth (Digger)uses this media so if its suitable for him there really should be no problem.

Ah, well there you go then.


Cyclebs are dangerous!

There is a direct relationship between using cyclebs and driving into trees.

Hey Sparky, I've used a sewing machine motor for the past 3 years and I use lead media. I made it as a temp but it's never faulted so I'm still using it.

It's like this one but I swapped the foot peddle for a light dimmer switch, "simples"



http://www.ebay.co.u...=item35be1a4bc8

Thanks Dean

I'm currently putting together the roller part of the mill. I've got a jar, media and all the pieces except the motor. I think once I've got everything ready I'll be able to work out what is most suitable and available and in budget :-)

I think mine is going to be quite posh though compared to what I've seen around

think about running costs?, using more motor than you need for hours and hours

Em, well being the type that smiles when feeling a cool motor i was thinking of a .75 kw motor lol.
Its interesting to see how people do things in different ways, ie "V" belt vs Timing belt, driving both rollers rathe than one + idler its all good.

Reading about it seems about 80 rpm is optimum, does anyone use two barrels and share the charcoal between the other two ingredients

and mill separately then either mill together for a short period or sieve together?

Ok my mill is coming along nicely now and I've actually ended up making one a little bigger than I first planned. Mainly due to the act I want to be able to mill my own charcoal and it will do small BP batches too.

For the larger stuff I have a 3 litre jar from Cooperman with a 20cm diameter. My questions are for this one how much media and what size should I use and also how fast should it rotate in RPM. I was heading for about 80 RPM.