AzoMittle Posted July 10, 2016 Posted July 10, 2016 I recently learned via a Lloyd posting that my ball mill needs significantly more media in it. I currently have Corbett's 3oz but it looks like that it is no longer being sold: https://www.amazon.com/Lead-Balls-Pre-tumbled-Charcoal-Pre-seasoned/dp/B00KLJMLIY?ie=UTF8&*Version*=1&*entries*=0 Can anyone recommend some media? Alternatively, could anyone cast some 3oz lead media for me? I have the Thumbler's Tumbler, using about 20 of the 3oz balls fills it around 1/8th of the way, I'm worried about straining the motor. https://www.amazon.com/Heavy-Duty-Rotary-Tumbler-Capacity/dp/B000BUXY0W/ref=sr_1_1?ie=UTF8&qid=1468115230&sr=8-1&keywords=thumblers+tumbler
otto Posted July 10, 2016 Posted July 10, 2016 Your 3 oz. media is pretty large for a jar that size. In addition to more I believe you would also benefit from smaller media. Much smaller. I have a similar size Lortone jar, a 20# capacity I think, that requires about 2600 .50 inch balls to fill half-way. At about 10 grams per piece it's over 58 pounds of media....... Smaller media is easier to come by (perhaps) and certainly a more efficient grinder to a much finer result. Think of multiplying the grinding surfaces times 8 or a little better. The little balls do their work very well. Check with Caleb on site. I understand he has some very nice media available. As for me, I pour my own........ And yes, if it's a stock Thumblers motor it will be taxed with a proper charge in the jar.
DavidF Posted July 10, 2016 Posted July 10, 2016 I don't understand the logic of using larger media when using a larger mill jar. It does not seem to me that milling efficiency can be 'scaled up' that way. If 1/2" media is 'ideal' for a 6" diameter jar (which I don't think is necessarily true), what size media would be best for a 12" diameter jar? Wouldn't any increase in media size simply be a step backwards in efficiency? If the media can do the job at (let's say) 3/8" diameter in a 6" diameter jar, by what logic would its size ever be increased, just because a larger jar was used? If anything, I would think that 3/8" media that worked well in a 6" diameter jar would work as well or better in an 8 or 12" jar. If it does indeed work better, wouldn't larger media work less better?
Mumbles Posted July 10, 2016 Posted July 10, 2016 I agree with everything you just said. The one advantage a larger size has is that if casting ones own media, it's less troublesome to pour fewer, larger pieces. If I'm buying though, I'm going optimal size. I don't know exactly where that is however. In my mind there's a trade off between ability to crush larger particles and milling speed or efficacy.
AzoMittle Posted July 10, 2016 Author Posted July 10, 2016 Yup, it is the stock tumbler/jar/motor/roller/etc. I don't know much about the theory/practice of ball milling and can't remember how I settled on the 3oz lead, but that's what I have at the moment. I know there has been a few threads regarding what the media is made out of but I have no idea what the optimal size is either (obviously), hopefully Lloyd will chime in on all of this. I really need to buy his book one of these days. So far, I have at least one vote for .50 balls, something like this: https://www.amazon.com/Traditions-ROUND-BALLS-490-100PK/dp/B0029LYYP0/ref=sr_1_1?ie=UTF8&qid=1468128525&sr=8-1&keywords=50+caliber+lead $250 for the tumbler + S&H is a lot of money for me, I want my equipment to last me for as many years as I can make it.
otto Posted July 10, 2016 Posted July 10, 2016 You can spend a good amount on a mill but often a proper amount of media can be as big (or bigger) investment. Do the math on 2600 balls @ $20 per 100. Yeah... Do check with Caleb. Here's a dated link but it will give you a better deal plus he's "one of us". http://www.amateurpyro.com/forums/topic/10999-lead-media-sale/ To get close to how many .50 balls you will need just fill your jar with water, measure how much there is and divide by 2. .50 balls occupy roughly 1 cc of space so if you can convert (or directly measure) to cc/ml you would be very close. As far as that goes you could weigh the water (in grams) and divide by 2, same deal. 1
AzoMittle Posted July 10, 2016 Author Posted July 10, 2016 Quick question, does more media = a higher quality BP? or, does more media = less milling time? or both?
otto Posted July 10, 2016 Posted July 10, 2016 Quick answer: I'd say both. Now you can probably make quality BP with less media if you're willing/able to let it run. There are issues with that: A.) It will wear the media you have faster with less product in return for the wear, B.) If your mill is outside (where it ought to be) the weather could complicate matters. Like rain before you're finished. C.) Lots of testing to determine when you're finished rather than knowing a mill with proper media and charge should be done in 3 - 5 hours. Once you get dialed in that number is even more predictable. I made a smokin' deal for an unbelievable mill. I happen to have been into casting lead for fishing lures for decades so pouring my own media wasn't much of a stretch for me. Despite that I spent around $150 for just over 100# of foundry type (very hard and a more efficient grinder). So I wound up with 3 20# jars and a 1/2 TEFC drive plus enough hard lead to fill two of the jars for about what you got just in your mill. And just recently I invested in a pile of zircon media. Very efficient, great BP in around an hour...... :-) Bottom line: BP is probably 80% of what anyone wants to do in pyro. I still have more time than $$ but if I were starting (and I still kind of am) your most basic tool should be your best one. Bite the bullet and do it right. I promise, you will not regret the investment. 1
OldMarine Posted August 5, 2016 Posted August 5, 2016 Caleb has lead media on his site: woodysrocks.com
Arthur Posted August 7, 2016 Posted August 7, 2016 I like alumina media for use in a rock tumbler. With lead media the motor will stall before the jar is full enough to mill well.
otto Posted August 8, 2016 Posted August 8, 2016 I like alumina media for use in a rock tumbler. With lead media the motor will stall before the jar is full enough to mill well. C'mon man......Just get a bigger motor. Original probably isn't TEFC and you would benefit from that in the long term with the upgrade. Like I said in another post: BP is probably 80% of what you will do in pyro so make the right investment up front and you will never be disappointed. 2 cents - ka-ching!
AzoMittle Posted August 8, 2016 Author Posted August 8, 2016 C'mon man......Just get a bigger motor. Original probably isn't TEFC and you would benefit from that in the long term with the upgrade. Like I said in another post: BP is probably 80% of what you will do in pyro so make the right investment up front and you will never be disappointed. 2 cents - ka-ching! I'm interested in everyone's 2 cents, so please throw it at me! Do you think the motor in the Amazon post I originally linked to is 'good enough' quality or should it be upgraded? If so, why and to what? I'm strapped for cash right now so this would be a 'down the road' upgrade but all the same it is good to know. In case anyone is curious I took Mumbles advice, I tested some meal BP on a sheet of printer paper. I used the media and mill linked above, I milled 2kg of standard BP with the jar being filled (roughly) 25% with 3oz lead media, and milled for 6 hours. I placed roughly 2 or 3 tablespoons of BP in a pile on the paper and lit it, it burned in a single instantaneous 'poof' but did cause the paper to catch fire; it was hard to tell but I believe there was a very small amount of bubbling drag in the center of the pile. I have used this same BP for my burst and lift previously with good results.
Mumbles Posted August 8, 2016 Posted August 8, 2016 Just as a note, I don't use nearly that much. I test maybe a gram or so. You used, I dunno, maybe an ounce? I don't know if the quantity changes the results our outcome. It sounds pretty good though regardless.
otto Posted August 8, 2016 Posted August 8, 2016 Your stock Thumblers motor will be marginal with a proper charge of lead (50 - 60 lbs depending). That motor may stall on starting and you will likely need to give the drum a spin by hand to get it going. Even after that it will most certainly run warm or even hot shortening its life. Caleb has a similar setup (though not especially for "limited budgets") that you can get some ideas from. http://www.woodysrocks.com/store/p93/Rebel_Base_Upgraded.html He has upgraded to a 1/8 hp motor and while I have no first hand experience with that I'm sure it's a solid upgrade for the size. Upgrading on your own isn't necessarily costly if you have a few machinery modification skills. A quick search turned up this 1/4 hp TEFC on eBay: http://www.ebay.com/itm/Motor-1-4HP-Leeson-1725rpm-1Ph-60Hz-Fr48Z-TEFC-C4C17FZ5-5B-Missing-JunctionBox-/261869250326?hash=item3cf89fa716:g:rfwAAOSwmrlUsFkF The junction box is something you could adapt from most hardware store electrical departments. The (slightly) more challenging would be to find a 1/2 shaft with a keyway to fit the female access to the motor as well as the correct size pulley to match the remaining drive. All in all (there's other folks watching the item) $40 including S/H is a steal and would power that mill into the next century. Heck offer the guy $15 and see what happens. Now I'm even tempted to buy it...... I'm sure it could be useful somewhere down the line. Keep an eye on eBay and there are deals to be had. Make sure the motor will run on 110 - 120 volts so you won't need special a electrical source (disregard if you are not in the US) and that the motor is single phase.
AzoMittle Posted August 9, 2016 Author Posted August 9, 2016 (edited) Your stock Thumblers motor will be marginal with a proper charge of lead (50 - 60 lbs depending). That motor may stall on starting and you will likely need to give the drum a spin by hand to get it going. Even after that it will most certainly run warm or even hot shortening its life. Caleb has a similar setup (though not especially for "limited budgets") that you can get some ideas from. http://www.woodysrocks.com/store/p93/Rebel_Base_Upgraded.html He has upgraded to a 1/8 hp motor and while I have no first hand experience with that I'm sure it's a solid upgrade for the size. Upgrading on your own isn't necessarily costly if you have a few machinery modification skills. A quick search turned up this 1/4 hp TEFC on eBay: http://www.ebay.com/itm/Motor-1-4HP-Leeson-1725rpm-1Ph-60Hz-Fr48Z-TEFC-C4C17FZ5-5B-Missing-JunctionBox-/261869250326?hash=item3cf89fa716:g:rfwAAOSwmrlUsFkF The junction box is something you could adapt from most hardware store electrical departments. The (slightly) more challenging would be to find a 1/2 shaft with a keyway to fit the female access to the motor as well as the correct size pulley to match the remaining drive. All in all (there's other folks watching the item) $40 including S/H is a steal and would power that mill into the next century. Heck offer the guy $15 and see what happens. Now I'm even tempted to buy it...... I'm sure it could be useful somewhere down the line. Keep an eye on eBay and there are deals to be had. Make sure the motor will run on 110 - 120 volts so you won't need special a electrical source (disregard if you are not in the US) and that the motor is single phase. Awesome, thank you for the detailed write up! I put in the $15 offer like you suggested. I can do the 1/2" shaft for sure but I have no electrical engineering experience. What would I need to do in order to get this thing wired up? (I'm in the US and would have access to a standard wall-mounted electrical outlet.) Edited August 9, 2016 by AzoMittle
memo Posted August 9, 2016 Posted August 9, 2016 azo I use 3 0z. lead balls about 200 of them in a rebel 17 jar. the weight is about 38 lbs. it will mill a kilo of bp in 2 hours. it is tuning about 60rpm I have a home built mill 3/4 steel rollers with 3/4 clear plastic hose over the steel. I use the cheapo pillow block bears from china about 5.00 ea. I built mine to handle 2 jars. I am only running 1. buying another jar and lead is in the future. it sounds like you are on the right track and getting a tefc motor is a must. I bought a new 1/2 hp telf grizzly motor , it was about 150 bucks. good luck and keep us posted. memo
otto Posted August 10, 2016 Posted August 10, 2016 Awesome, thank you for the detailed write up! I put in the $15 offer like you suggested. I can do the 1/2" shaft for sure but I have no electrical engineering experience. What would I need to do in order to get this thing wired up? (I'm in the US and would have access to a standard wall-mounted electrical outlet.) Keep a close eye because it's a good deal it will likely go at some point. If seller doesn't take your offer don't let $4 stand in the way of your upgrade, just buy it. Wiring is easy. I can get you through that. Electrical engineering degree not necessary.....
AzoMittle Posted August 17, 2016 Author Posted August 17, 2016 Keep a close eye because it's a good deal it will likely go at some point. If seller doesn't take your offer don't let $4 stand in the way of your upgrade, just buy it. Wiring is easy. I can get you through that. Electrical engineering degree not necessary..... azo I use 3 0z. lead balls about 200 of them in a rebel 17 jar. the weight is about 38 lbs. it will mill a kilo of bp in 2 hours. it is tuning about 60rpm I have a home built mill 3/4 steel rollers with 3/4 clear plastic hose over the steel. I use the cheapo pillow block bears from china about 5.00 ea. I built mine to handle 2 jars. I am only running 1. buying another jar and lead is in the future. it sounds like you are on the right track and getting a tefc motor is a must. I bought a new 1/2 hp telf grizzly motor , it was about 150 bucks. good luck and keep us posted. memo UPDATE! The motor showed up today. It looks to be in new condition. So how can I get this thing wired up safely? I'd definitely like to add some redundant safety measures and if possible a speed control, so where do I go from here? I haven't bought the key shaft yet, I saw a few on ebay and I know McMaster-Carr sells them too though, I want to make sure the motor itself actually works before I get that stuff.
otto Posted August 17, 2016 Posted August 17, 2016 Hah! It was you that got it. Good deal... Wiring is easy if you've done any wiring at all. There are six wires coming from the motor. They should be identified T1 - T5 and T8 (usually). The diagram is right on the motor spec plate. It would look something like this: You will want the low voltage configuration. On this diagram (check the diagram on your motor, it may be different) you would twist T1, T3 and T8 together for one and T2, T4 and T5 together for the other. Twist in you leads from the power cord, it really doesn't matter which goes to white and which goes to black. Secure the connection with proper size wire nuts. Don't forget to connect the green wire from your power cord to a ground on the motor case somewhere. Often there will be a hex head screw that is painted green for that. Note that this basic configuration will have the motor rotating Counter Clock Wise (CCW). To get it to spin the opposite direction swap leads T5 and T8 and proceed as usual. Be advised if you don't find a small junction box you will lose the sealed of the motor and can risk explosive dust entering where a spark could ignite it. Additionally a junction box will have some sort of a cord restraint so your connections aren't constantly flexing with the risk of a wire nut coming off and being exposed to a shock hazard.
otto Posted August 17, 2016 Posted August 17, 2016 (edited) OK, I got a pic of your actual motor plate: It looks a little different but what I said in the previous post works for your motor. Also check the circled area for the ground connection: As for a junction box, you could check the area for a place that repairs electric motors. They may have an unrepairable one that could be scavenged for parts. Or if you're on good terms with the maintenance department where you work it might be worthwhile asking them if there's something laying around..... Edit: That was weird. Got an error that I can't post too quickly together and I have to wait "14 seconds" and try again. When I did it recopied everything into the same post. I deleted the doubled information. Edited August 17, 2016 by otto
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