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media in ball mills


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Posted
does anybody have anything to say either way about using nickels?
Posted

I don't think the nickles have the mass to do a good job.

 

I tried soft lead just once, and the erosion was phenominal. Never again. Adding tin or antimony would help, and so would pouring molten lead into short sections of Cu pipe, but in the end, unless we can get the chinese to ship us a cheap pallet of true stainless media, the best solution is to get 3 to 5 brass or stainless rods, 1/2" to 3/4" OD, and saw media off of them. With just a hacksaw, it is a grueling ordeal, but once done, the media works very well and lasts forever. Brass stains, and it does contain copper, which may be a factor for some comps.

 

Cut media in this way can be deburred by tumbling it with water and a coarse abrasive similar to those used in rock tumbling. Anyone who bought a "Hobfir" ball mill off eBay probably got some abrasives with it; don't throw it away, it's useful stuff.

 

I recently tried some of my new stainless media, and its awesome, my favorite media bar none. Dense, doesn't stain or rust, hose it down to clean. I like ceramic media very much but do restrict it to individual chemicals, not BP or BP-based stars.

Posted
I've used nickles before and they are a good starting point. Right now I've got a mix of tire weight lead (which a friend told me was 5% antimony) and nickles and its been working great so far, but its only had a few runs. Instead of using lead balls or cylenders, I just made lead 'nickles', which were easy to make.
  • 1 year later...
Posted

Bump...

 

Just bought 12 (100 ct) boxes of Hornady 50 CAL lead round balls. Four of the boxes contained balls that were a dull lead color - as you would expect. Eight of the boxes contained balls that were noticeably shinier. They kind of look the color of stainless steel but duller. So I took one of each of the balls and put them on the scale. Their weight is identical. The labeling on all the boxes is identical.

 

Do I have any reason to be concerned about the shiny balls? I'm sure there is someone here ho has run across this before.

 

Thanks for looking.

Posted

it may be oil, ive heard to just mill a batch of comp with it and then toss it out and the balls will be clean

 

 

Posted
I'm hoping the shinier ones have been hardened with antimony. The labels on the boxes say pure lead. And I know you don't want pure lead.
Posted
One box was probably just fresher than the others. Fresh lead balls are shiny, but tarnish over a period of time. You wont find general use 50 cal shot that has been hardened. It would potentially harm the guns they're designed to be used in.
Posted
Then is this the wrong stuff to be used? And if so, what should I be looking for?
Posted

Then is this the wrong stuff to be used? And if so, what should I be looking for?

 

I'm not one who uses my ballmill every day, but two years ago I got three boxes of 100ct 50cal lead shot... I can get good powder in three hours and have not noticed any wear on the lead. I think it depends on what your milling, my sulfer is already dust, and my potassium nitrate is (or was... I'm out) fairly fine, charcoal is soft. So the only thing that would put that much wear on the media would be the PVC jar, and thats smooth, or the lead itself.

 

I've never tried milling a batch of potassium nitrate alone to check how gray it becomes.

 

Also, how much did you pay for each box? I need three more boxes if I ever want to be able to run both my jars. 12 and the cost adds up if they are about 20 each (I think thats what mine were)

Posted
I paid $13.99 per box at Sportsman's Warehouse and the total cost was $168.20 with tax. Looking at the receipt right now I was only charged for 11 boxes.
Posted

Thanks, guys. Time to go mill.

 

Remind me again why you can't edit your posts?

Posted

I use those same Hornady lead balls - I paid $11.99 a box (100) at Bass Pro Shop. I haven't noticed any significant wear or loss of weight, though they are starting to look a little pitted. I've milled nitrate alone and it comes out a little gray, but I can't decide if it's lead or lampblack from the rubber jar - I suspect the latter, since the jar will mark a paper towel if I rub hard.

 

Hardened balls (Missouri Bullet Co) can be had from Graf and Sons, but the shipping costs will be painful.

Posted

Remind me again why you can't edit your posts?

 

Sorry, I was thanking you and Mumbles for your response to my question.

Posted

Is it okay to mix differant size media. say 1/2, 3/4 & one inch?

If no, why?

 

 

Posted

Using 1/2 inch media in mills 6" or smaller mills is preferable. The amount of milling media and the amount of mixture to be milled is the key thing. Read Lloyd Sponenburgh's "Ball Milling Theory and Practice For The Amateur Pyrotechnician" for the detailed answer.

 

Stick with the same size media. Fill your barrel halfway full with milling media. Then start adding your mixture. Shake the barrel until the mix settles into the voids between the balls. Continue doing this until all of the voids between the balls are filled. Then you want your mixture to slightly cover the top balls. For the HF mills, this amount is about 100 grams.

 

But your mill needs to be turning at a certain speed to create a desired cascading of the media for optimal milling. Again, get the book. Good luck.

Posted (edited)

Wise idea to buy the book. so, I just ordered it.

 

Even wiser to read-study it before I construct my mill.

 

I have the little harbor freight mill.

But, want a far bigger, more rugged one, which I intend to build.

As I want one capable of milling down large batches of bulk single chems & also mg/al.

 

Basic design with 1 inch rod rollers & pillow block bearings.

Plan to add an idler arm to allow adjustment of belt tension.

gallery_10713_78_18539.jpg

 

12 inch sewr pipe pvc for jars.

Plan on 12X14 or 16 inch jars

gallery_10713_78_39857.jpg

 

I have this motor on hand.

gallery_10713_78_36984.jpg

 

But, now will wait & may buy a new TEFC 1/2 hp motor.

 

I bought 10 lbs of anitomy shot & have about 150 lbs of lead.

Plan is to melt & cast it all into 5/8ths inch round hardened balls.

 

I also bought a lot of stabilized YSZ & M stabilized zirconia milling media.

gallery_10713_78_111844.jpg

This stuff is VERY heavy & harder than steel.

It mills like I would never believe unless I had seen it myself.

 

There was some question if this media would produce a spark.

In total darkness, I used a wrist rocket sling shot & fires a few at close range at an angle into a high carbon steel plate.

As much as I tried, I could not produce a spark with it. So, I believe its safe to use, even with reactive metals.

 

I have melt/cast almost 100 lbs of 50/50 mg/al.

I have a lab sized rock crusher to bring the mg/al down to under 1/4 inch minus.

Plan is try billard balls to mill it down to around 30 to 60 mesh.

Then use the zirc media to mill it finer.

 

LOL, 6 ways one way & 7 the other, but it's all coming togather.

Edited by oldguy
Posted
Then use the zirc media to mill it finer.

 

Does zinc media work well? I was about to buy some galvanized steel today, but figured I better check first.

Posted

Wise idea to buy the book. so, I just ordered it.

 

Even wiser to read-study it before I construct my mill.

 

I have the little harbor freight mill.

But, want a far bigger, more rugged one, which I intend to build.

As I want one capable of milling down large batches of bulk single chems & also mg/al.

 

Basic design with 1 inch rod rollers & pillow block bearings.

Plan to add an idler arm to allow adjustment of belt tension.

gallery_10713_78_18539.jpg

 

12 inch sewr pipe pvc for jars.

Plan on 12X14 or 16 inch jars

gallery_10713_78_39857.jpg

 

I have this motor on hand.

gallery_10713_78_36984.jpg

 

But, now will wait & may buy a new TEFC 1/2 hp motor.

 

I bought 10 lbs of anitomy shot & have about 150 lbs of lead.

Plan is to melt & cast it all into 5/8ths inch round hardened balls.

 

I also bought a lot of stabilized YSZ & M stabilized zirconia milling media.

gallery_10713_78_111844.jpg

This stuff is VERY heavy & harder than steel.

It mills like I would never believe unless I had seen it myself.

 

There was some question if this media would produce a spark.

In total darkness, I used a wrist rocket sling shot & fires a few at close range at an angle into a high carbon steel plate.

As much as I tried, I could not produce a spark with it. So, I believe its safe to use, even with reactive metals.

 

I have melt/cast almost 100 lbs of 50/50 mg/al.

I have a lab sized rock crusher to bring the mg/al down to under 1/4 inch minus.

Plan is try billard balls to mill it down to around 30 to 60 mesh.

Then use the zirc media to mill it finer.

 

LOL, 6 ways one way & 7 the other, but it's all coming togather.

 

Sweet Mary!

Posted (edited)

Sweet Mary!

 

:o I just realized how many lbs of grinding media it would take to half way fill a 12 X 16 inch jar.

 

gallery_10713_78_126078.jpg

25 lbs per gallon

 

Hell, it would take about 2.5 gallons, or 62.5 lbs of this particular media.

 

2 jars that size half full would weigh in well over 120 lbs.

 

So, I may go with a single jar.

Edited by oldguy
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