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Ball mill media


hochroter

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United Nuclear is out of stock of their 1/2 lead media...they haven't gotten back to me on future availability.

 

The ebay media looks kind of trashy, unless someone can chime in on their experience.

 

Sky lighter is also out of stock, id rather not since they are so expensive.

 

Im kicking myself in the arse for throwing most of my pyro stuff out years ago :angry: :wacko:

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Go to where you buy tires from and get some wheel weights. This will be the cheapest way. Do not heat over 600 deg. F.

http://www.ebay.com/sch/Round-Ball-Bullet-Molds/71118/bn_1938908/i.html

Edited by dynomike1
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Most tire stores will NOT convey lead weights to 'ordinary citizens' anymore, even though they must PAY to recycle them.

 

If you have a local small shop, they might be able to fix you up.

 

Beware that not all wheel weights are lead, anymore. You'll have to hand-sort them. Also, get thyself some linotype alloy with which to harden the lead.

 

Lloyd

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Some day, some day, I'm going to make a small foundry that can do 3000F, make a graphite mold, and cast my own brass milling media from scrap brass.

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Don't miss the fact that copper compounds won't hurt BP milling, but might be undesirable if you were milling (say) a chlorate or perchlorate.

 

Lloyd

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Most tire stores will NOT convey lead weights to 'ordinary citizens' anymore, even though they must PAY to recycle them.

 

If you have a local small shop, they might be able to fix you up.

 

Beware that not all wheel weights are lead, anymore. You'll have to hand-sort them. Also, get thyself some linotype alloy with which to harden the lead.

 

Lloyd

 

Yeah I found out years ago that wheel weights are usually 75% lead and the other is tin...probably not a good idea.

 

Oh yeah thanks for the link lloyd spot on!

Edited by hochroter
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Heres a great link explaining wheel weight composition and how to tell if they are lead, steel, zinc etc. I was lucky enough to run into a few hundred pounds of linotype 10 years ago so I used it for making my media (also for reloading), I believe its 12% antimony and its hard as can be.

 

http://castboolits.gunloads.com/showthread.php?139839-Guide-to-Hand-Sorting-Wheel-Weights

 

 

 

Almost forgot, copper was used for years to add some hardness to some "type setting materials". The amount is probably minuscule but worth noting here.

Edited by uncrichie
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Yeah I found out years ago that wheel weights are usually 75% lead and the other is tin...probably not a good idea.

 

That's really not a problem. The problem is that a lot, more and more, wheel-weights, are zink, which melt at a similar enough temperature to be a problem, if your not careful.

B!

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If you need lead you need to befriend a plumber! Most old homes and businesses have leaded cast iron drain lines. Though I do little residential repair anymore I still come up with several hundred pounds of lead every year. You can get more good quality lead from 10 4" cast iron joints than from a bucket of wheel weights.

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Do you alloy that stuff with Linotype or antimony Patrick? I can get all the soft lead (lead pipe, joint filler, roof flashing)I want from work, but never knew if it would be worth it to alloy it, and make it hard enough for mill media. I guess at the worst I could use it for the .50 call muzzelloaders.
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I realize that part Lloyd. What I meant was if it was worth it financially. I can get Linotype ingots (which I use for my current media) for about $15-$18 for 5lbs. Or a 30% antimony alloy for about the same price. Just wondering if its worth the hassle to alloy it myself.

Do you recommend a hardness or alloy to shoot for Lloyd?

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I think if you talk to the guys manufacturing commercial amounts of 1/2" media you'll find they use 50/50 lead to linotype which would produce lead with 6% antimony which is hard enough. I used 100% linotype (12% antimony) when I made my media and its very hard and puts a lot of undue stress on your mold and is miserable to cut the sprues off the ball but produces excellent media. Pure antimony can be added to molten lead but takes a certain amount of flux and must be done at about 600 degrees for good results. A process probably best left for a smelter. That's the reason people use linotype or other "type set" metal for the antimony content, the alloying work is already done for you . I can tell you after pouring and cutting off sprues for 100 lbs of media my hands cramped up and hurt for about a week (I'm an old guy). It was a fun learning experience but I'll never do it again. After you consider your time, materials, blisters and lead spills on the garage porch floor, you'll find the price these guys charge on the forum and elsewhere for the finished product a real deal and worth every penny! Kurt

Edited by uncrichie
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Unc,

 

I feel your pain. I cast my own media a year or so ago. I got 50 lbs of Linotype, a 12 place mold, and a bottom pour melter. I said it then that if I had to do it again Id just buy it. I used straight Linotype for that run. After I got the hang of using the mold the media turned out great, but I have alot of wear on the mold. I was just curious, since I have the tools, and can get the soft lead pretty much free, if it was worth trying to get some high antimony alloy, and make up some spare media.

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Chuck, when I was pouring my own I got an ingot of antimony from eBay and alloyed it myself and then my brother got me some Linotype. What I did not have was a mold that would pour 35lbs of media in one fell swoop so I broke down and bought the rest!

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Chuck, oh yea its always worth it. It saves time not having to clean out old media for a different mill run. I would probably do it again 5-10 pounds at a time in between bullet casting (another hobby). I originally used a gang mold like the one you describe but didn't have the hand strength to open the handle to cut off 12 sprues when using pure linotype so I only used 6 of the cavities which helped. Then I found using a fishing sinker mold with 12 cavities worked better but the balls were all connected to each other by a network of sprue channels that had to be cut off with diagonal cutters. I had to keep switching hands for the cutting process. What we won't do to try and save a buck, and usually don't.

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Lol yeah I spent more money then if I would have bought it from Caleb. But its fun to try new things. And I still have the tools. Me and my friend have .50 cal muzzelloaders too, so I could always use the mold, and soft lead for free bullets.

 

Patrick,

Did you have a hard time getting the antimony to melt and alloy with the pure lead? Vie heard that can be a problem. Also a bit of a health risk.

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No' I have a bud who pours fishing lures for a living and he can ramp the heat up in his bottom shot pot to ludicrous degrees. I broke the bar up in the vise and it looked like Gollum going down in the lava. He poured it into one pound increments for me then I came home and decided it sucked too bad to mess with!

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Chuck,

I'm not an expert on alloying lead media. It's best to get advice from folks like Unc, who've done it enough to know.

 

I have cast a LOT of pure lead media, but have always purchased hardened media.

 

Lloyd

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Alloying the metal is pretty straightforward and not hard, Take respiratory precautions and be sure you wash your hands before sucking your fingers but otherwise just get the lead plenty hot and stir your antimony in with a metal rod while tossing in sawdust and beeswax to keep the top fluxed. You'll see when the metals alloy and then you add more sawdust and wax and stir for a few more minutes then done!

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Thanks everyone. I've only done it once with pre-alloyed Linotype. I've just been thinking about setting up a few more jars for milling other chems, without having to clean the contaminated media between runs. Having a cheap supply of pure lead handy got me thinking about alloying my own (thinking again) so I thought Id ask. If I do it I think Id get the pre-alloyed 30% antimony/70% lead ingots and mix with pure lead accordingly. I could make up about 20 lbs of 10% antimony lead with one 5lb bar or super hard alloy and 15lbs of soft lead. For $20 or so it might be worth a try.
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I think if you talk to the guys manufacturing commercial amounts of 1/2" media you'll find they use 50/50 lead to linotype which would produce lead with 6% antimony which is hard enough. I used 100% linotype (12% antimony) when I made my media and its very hard and puts a lot of undue stress on your mold and is miserable to cut the sprues off the ball but produces excellent media. Pure antimony can be added to molten lead but takes a certain amount of flux and must be done at about 600 degrees for good results. A process probably best left for a smelter. That's the reason people use linotype or other "type set" metal for the antimony content, the alloying work is already done for you . I can tell you after pouring and cutting off sprues for 100 lbs of media my hands cramped up and hurt for about a week (I'm an old guy). It was a fun learning experience but I'll never do it again. After you consider your time, materials, blisters and lead spills on the garage porch floor, you'll find the price these guys charge on the forum and elsewhere for the finished product a real deal and worth every penny! Kurt

 

I've cast lead fishing jigs/sinkers for decades. Not difficult, but proper tools help a lot. When I got the bug to cast my own media I already had a .50 cal mold for round balls. I poked around a little bit and discovered there's a few "levels" of type alloys that are available.

 

Linotype, despite its reputation as a hard alloy, is the softest and most available. Increasing in hardness and scarcity are monotype and then foundry type. I bought into a pile of foundry type and cast my media straight, exploiting the superior hardness without dilution. As a result I didn't feel the need to quench though the finished product would certainly have been even harder. Out of the mold the hardness made the cast so brittle sprues snapped off very cleanly when fresh. Once cooled even a bit they were almost impossible to snap much less cut. My media is very satisfactory and will likely last as long as I want to use it. I guess we'll see....

 

There's also a tradeoff in media. You can't have maximum mass AND maximum hardness. As your lead alloy increases in hardness those very additions make the alloy less dense piece for piece. I don't have a calculation for hardness vs mass in a grinding media but I'll bet there is a tipping point and I don't know where that might be. It's probably dependent on what you're grinding and how far you want to take it.

 

Casting your own isn't difficult and can keep you in media as long as you've got raw material.

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"I don't have a calculation for hardness vs mass in a grinding media but I'll bet there is a tipping point and I don't know where that might be."

---------------

I don't either, Otto, but I'm betting it makes no difference. The reason I say that is that the next less dense medium would be steel (stainless steel), and that's VERY much less-dense than any lead alloy you could think of.

 

Lloyd

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Oh the joys of casting lead..

 

Wheel weights.. yak they are down to almost 50% trash..
lead from flashing. not bad , but big and dirty

I get my lead off of ebay in precast ignots now. I get an already hard blend. and then add linotype to it.

I've poured straight lino, and used foundry. Both I didn't like and didn't get my moneys worth in both stress and tool wear.

I can get 1000 lbs of media out of a mold now which is acceptable. I have my eye on an automatic caster at the moment. It's hard to drop lead and run machines at the same time. :)

I do water drop mine/ dry them, and fill a mill jar up darn near full and then run them overnight to clean them up. Then I pick out all the oddball/ junk i can find.

It's work , but I have a pretty good system now after running 5 or 6 thousand lbs of it.

 

I believe united nuclear gets mine.. and some other guys as well.

Once you get clean materials and a nice groove it's not too bad of work.. The first couple 1000 lbs really really sucked as I figured it out. :)

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