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More like the one from Dan Williams site. His is a smaller type and it works for the smaller jobs but can be scaled up if needed. His web site is: http://www.brianredmond.net/dwilliams/top.html He has not up-dated it for a while. Look in the Tools section then into the ball mill build. His site and Dexter's sites were the first ones that hooked me. To bad Dexter's site is gone now............Pat

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I had a strange thing occur last night. I milled a load of BP for 4 hours using pre milled and dried KNO3 and willow charcoal. Everything passed a 40 mesh screen before going into the jar. I weighed out half of it this morning to screen in some dextrin and found that a good percentage wouldn't pass the 40 mesh screen. It almost looks like my nitrate somehow recrystallized in the tub overnight. Never happened before.

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It may have, no worries though, not enough water to make large crystals. I bet if you put it in a baggy and put it in the sun, you will have water droplets on the top of the baggy though.

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replacement barrels from HF took 10 weeks to get, better off buying a new one and you will have all the spare parts

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Bravo! At least you got yours! I had used cut stainless steel squares in my HF barrel a dozen years ago and it shredded it, I paid for two barrels and NEVER got them! I did get my money back after a LOT of phone calls and grumpy words and just bought a double tumbler, gave the old roller away and I was happy... for the moment.

 

Frankly, I only use Thumblers Tumblers now.

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I also had to have a lot of grumpy words,(I wont mention) some how my wife pulled it off after I have had enough, you sure get what you pay for at HF

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If you have large mesh charcoal (10-60 mesh) and place it in with other BP ingredients will a ball mill end up making it airfloat or does it need to be milled separately?

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If you mill it long enough it will reduce it to airfloat. Charcoal pulverizes easier than the KNO3. I premill mine now upon recommendation of DaveF. He makes some awesome rockets using red oak charcoal which is considered to be a "slow" coal yet he gets very hot powder from it by premilling it with small stainless steel media.
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I have been working a lot on gaining a better understanding of milling, and of black powder lately. I have proven (to myself) that 'supermilling' charcoal alone with tiny media will make excellent black powder with simple screen-mixing. One day an open-minded guru will try it and then others may follow his lead;) Gotta find the guy first.

 

The idea that milling media has to be large enough to smash the charcoal is just plain wrong. That's right, I said it. WRONG! The opposite (small media that 'rubs' the charcoal into submission) works way better. Don't debate it. Don't quote gurus. Try it- please!

 

To further prove my point- reported elsewhere earlier- I did another experiment last week. I found that a modified toy rock tumbler (75RPM) can mill willow charcoal well enough at -40 mesh starting size to make screen-mixed BP that kicks Goex in the ass. So, I took +12 mesh charcoal from the same master batch, and repeated the experiment. I milled 50 grams of it for 6 hours in the same jar with the same 5/16" dia. S.S. media at the same speed. Again I screen-mixed a batch, pucked and corned it to 2FA size, and re-tested. I used the same baseball flight time method as I have used for a lot of tests lately. This test uses 10 grams (.4oz) of powder in a lift cup, and a standard baseball.

 

The difference in flight time between a starting particle size of -40 mesh, and 10-12 mesh was 1/10 second. That's right. You can mill coarse charcoal with a toy and make excellent black powder without milling black powder. -40 mesh gave a 9.9 second flight. 10-12 mesh gave 9.8. You can believe old generalized statements or you can believe test results that can be repeated. OR you can believe neither, and find out what's what yourself.

 

I suggest that there is a lot more yet to be learned about milling black powder. While many have stopped experimenting long ago, I continue to try new things. I like to learn. I set out 2 years ago with the goal of eliminating the need to mill complete black powder. That has been achieved. I will continue testing until the "Yeah buts" are also eliminated. That could take a bit longer:) Please excuse my cockiness. It is not borne of arrogance. I have simply learned that to get anybody to even listen nowadays requires not just proof- it requires 'big talk'. And if any guru wants to show their work and debate anything I've said- I'm game.

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I'd buy a ticket to that shootout...er.. debate!

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Thanks OldMarine!

 

http://www.craigballsales.com/aisi-304-stainless-steel/

 

A 2 minute search on the net brought this up. This is the size and type I am using. I'm sure a better searcher than I can find off-sized or dimensionally incorrect products for cheaper. 100 balls are $3.77. I used 623 (1289 grams) balls to exactly half fill a Lortone 3B jar. That's $26.39 for 1 jar worth of media. A beginner or hobbyist-level pyro can make hobbyist amounts of excellent black powder without milling black powder at all.

 

If you want to further simplify things and eliminate the pucking and corning, you can rice the powder instead of granulating. In that case, your baseball flight times will go up.

 

Once a hobbyist experiences immediate success with minimum outlay and minimum danger to self or others, they will probably want to scale up. Myself, I scaled down to prove this stuff. And I'm not near done yet. I have done hundreds of tests over several years with different milling jars, times, and media to slowly get to this point. This is not a flash in the pan situation.

 

EDIT: I got the number of balls mixed up with the weight of the balls. It's fixed now.

Edited by DavidF
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I have done several of the same experiments that David has and can confirm basically everything he's said. I was using 000 buckshot though. It's been my goal as well to achieve BP without milling any live compositions. Life has gotten in the way, and I haven't been able to do anything in several years however. Thinking back I clearly had a few issues with my materials and processes, but it does work.

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Question.

 

Which size of milling media are "recommended" for a tumbler barrel that is 4 1/8"(105 mm) (3 lb), anyone?

 

Regards

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I can only comment on what I have done. I have used the 5/16" 304 stainless steel balls to reduce charcoal from +12 mesh to 'supermilled' in 6 hours. Actually, I was quite surprised to get such great results. I used the same media load to mill 225 grams of potassium nitrate, greenhouse grade crystalline. I milled it for only 2 hours. after that time, maybe as much as half a gram did not pass the 100 mesh sieve. A longer mill cycle- or a larger diameter jar- would do a better job, but I can live with the result. Using 3/8" media of the same type for the same time left a 'bit' more nitrate on the screen. So, I'd recommend the 5/16" media linked to above.

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Question.

 

Which size of milling media are "recommended" for a tumbler barrel that is 4 1/8"(105 mm) (3 lb), anyone?

 

Regards

I have used ceramic media balls, about 8-9mm in diameter, and various sized lead balls. from 6mm to 1 inch.

Both works well, but I prefer the ceramic media. The lead balls tend to react with oxidizers if just a tiny amount of moisture is present.

 

This has not proven to be a dangerous reaction, but it wears down the balls. Anyway, the BP from both my barrels seemed to burn equally fast.

Edited by Ubehage
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Thanks OldMarine!

 

http://www.craigballsales.com/aisi-304-stainless-steel/

 

A 2 minute search on the net brought this up. This is the size and type I am using. I'm sure a better searcher than I can find off-sized or dimensionally incorrect products for cheaper. 100 balls are $3.77. I used 623 (1289 grams) balls to exactly half fill a Lortone 3B jar. That's $26.39 for 1 jar worth of media. A beginner or hobbyist-level pyro can make hobbyist amounts of excellent black powder without milling black powder at all.

 

If you want to further simplify things and eliminate the pucking and corning, you can rice the powder instead of granulating. In that case, your baseball flight times will go up.

 

Once a hobbyist experiences immediate success with minimum outlay and minimum danger to self or others, they will probably want to scale up. Myself, I scaled down to prove this stuff. And I'm not near done yet. I have done hundreds of tests over several years with different milling jars, times, and media to slowly get to this point. This is not a flash in the pan situation.

 

EDIT: I got the number of balls mixed up with the weight of the balls. It's fixed now.

 

Just a quick update: I decided to see just how small I could go with the charcoal milling media, in a Lortone jar. I contacted Craig Ball Sales but the online system did not allow me to order a package to Canada (shipping details). After a bit of back and forth, I suddenly found a box in my stoop this morning. I haven't even paid them yet! 2 thumbs up on the trust- and the service- for Craig Ball Sales! I will be trying 1/4" and 3/16" 304 stainless steel media, just to see how small I can go.

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Just a quick update: I decided to see just how small I could go with the charcoal milling media, in a Lortone jar. I contacted Craig Ball Sales but the online system did not allow me to order a package to Canada (shipping details). After a bit of back and forth, I suddenly found a box in my stoop this morning. I haven't even paid them yet! 2 thumbs up on the trust- and the service- for Craig Ball Sales! I will be trying 1/4" and 3/16" 304 stainless steel media, just to see how small I can go.

 

I think you're on the right track. The thing will be to start with appropriate sized charcoal for that size media. It's my understanding that while smaller media is not an efficient grinder of larger chunks it will grind already reduced material more finely than larger media. I'd think it's much like progressively finer grit for polishing rocks, the more coarse grades only get you so far. A more finely polished finish is achieved by finer grades of grit. Sharpening knives would be another analogy that would apply.

 

Keep us posted. I'm in the process of building a dedicated charcoal mill and that information will be very interesting to me.

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  • 2 months later...
Forgive me if i missed it somewhere, but when ppl say lift bars you are talking about ridges in the barrel to make the media jump a little
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Not exactly. They are not intended to make the media jump. Rather they are there to add friction in a sense. With smooth walled jars there is occasionally a problem with the media slipping and not efficiently tumbling. By adding in a lifter bar or two, the edge prevents the balls from constantly slipping and provides some additional "lift" so that the media properly cascades.

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  • 2 weeks later...
Quick question about media, would it work or would it be worth using 2 different sized media at the same time ie. Large and small. My thinking is the large would reduce particle size quickly and the smaller would refine it so much further than the large ever could. What does experience and common sense say here guys??
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"They" say media should not be of mixed sizes, because the large media will make the small media wear faster. I'd say that in the case of soft lead, that would probably be true. I'd say that in an under-charged jar of the same media it would be especially true. I've used mixed size media for most of my milling, but none that was made of lead. Milling charcoal by itself is hard on media- unless it's stainless steel :) I don't think anybody in our pyro world has done any tests to evaluate the efficacy of using mixed media, so it's just a matter of opinions, it seems. I guess a lot depends on what you are milling. Milling charcoal and milling black powder do not require large media, in my experience. Now, if you want to throw large chunks of charcoal in, the large media would help reduce it faster. But who does that?

 

Edited for sp.

Edited by DavidF
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Someone here or on FW was selling a small mill with mixed size media included. I never thought to ask them about it's performance.

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