Help with Ballmilled Black Powder

[TranslucentDragon]

Hello,

I need some help with the specific "types" of BP. I've been searching for a couple weeks on how to make black powder and, although I understand generally how to make it, I don't understand the specific parts. What I mean by that is: there are a lot of black powder tutorials out there, and even on A.P.C, that teach you how to add 75% KNO3, 15% Charcoal, and 10% Sulfur into a ballmill to make BP, but not specific techniques and varying types of BP.

 

My questions:

What are the stages of BP and what are they used for/how are they different (ex: what is pulverone, meal, and any other types of BP there are)?

 

What is screening (I know this doesn't pertain only to Black Powder, but I am deeply confused on what this is used for, how to screen correctly, and how the difference in the screen size affects powders)?

 

What is the "F" system (ex: F Black Powder, FF Black Powder, etc...)?]\

 

Is binding where you add dextrin to the BP to make it stick together and clump? If so, why is water added to the compound after it is finished?

 

Sorry for the rant, and I'm sure there is somewhere out on the internet where I can find this info, but I haven't found it, which is why I ask A.P.C. for the help.

 

Any help, even a link to the proper site to learn about BP, would be incredibly helpful. And, as always, I hope I haven't offended anyone here with the newb questions, but I do need to learn the basics.

Edited July 29, 2013 by TranslucentDragon

[Shadowcat1969]

Again, most of this is covered here in APC, in threads scattered throughout.

 

The stages of B.P.: As I understand it, you first start with your individual chemicals, weigh them and add to your jar. In the case of one of the jars from the mill you bought you will be shooting for 1/2" ball media to about half fill the jar, and that will allow you to mill about 150gr of finished B.P. per run. I only run one jar at a time on this mill, two jars is too heavy for it.

 

Once the chemicals have been combined and sifted through a screen (typically about 20 mesh) to integrate them, you would call that powder "Green Mix". If you put green mix (or just the KNO3, Charcoal and Sulfur) into the mill and run it, what comes out is "Pulverone". Pulverone needs further processing for MOST applications.

 

The next step is to granulate or press and corn you powder. When granulating you add a small percentage of Dextrin (5% or so) to the Pulverone that will act as a binder. In order for the Dextrin to activate and actually BE a binder, it uses Water, so that is where that comes in.

 

You would use this method of granulation by incorporating the Dextrin in by passing the pulverone and dextrin through the 20 mesh screen again 3 or 4 time, at least, then wetting into a "dough" ball and running the ball through about a 4 mesh screen (or kitchen grater) onto a drying screen.

 

After is has dried (NOT in the direct sun) you use the screens to "size" your powder. Anything that passes 4 mesh but not 10 mesh is pretty much 2 Fa (FFa)Grade and it's best application is in bursting small shells and such. If the powder passes a 10 mesh screen and not 20 mesh, that would be 3 Fa (FFFa)or 4 Fa (FFFFa) and is a good candidate for small shell lift. Passing a 20 mesh screen but not 40 will give around 5 Fa size and if it passes 40 mesh it is regarded as Meal (or Meal D). I tend to use 5 Fa and/or meal to make B.P. slurries for making blackmatch and the like.

 

The uses listed above are by no means the ONLY uses for the various grades of powder.

 

I also use a Pressing and Corning process for some of my powder. It results in a harder grain and I like it for certain specific things. To Press and corn you need to have a hydraulic press (an Arbor press may develop enough pressure, I do not know). You use a die to press your powder (with about 2% water, by weight) into solid pucks with a density of 1.44(? 1.77) gr/Cm³ After pressing to this density, you allow the pucks to dry completely, you break them back up into granules and screen them for size/grading as above.

 

Some of the above likely needs corrections to it, but I think I have the bulk of it correct.

 

I hope this has cleared up most of your questions, but I'm sure it has created new ones. I must say that I personally learned EVERY BIT of what I just wrote by reading posts on this site. My suggestion is to read EVERY post on the site and keep a notebook to write down things that you want to be sure to remember. If something being covered brings up a specific question, then ask for clarification. Most of what you will need to know (and have asked in your most recent posts) is somewhere here on the site. Keep digging man! We all are happy to help out anyone with questions, but if the questions that keep getting posted are all about things already here, we tend to get a little frustrated with someone that won't read what's already here. Don't be that guy, LOL, you seem interested in a good way and I'd hate to have people start thinking poorly of you.

 

 

[pyrokid]

Here is a nice skylighter article that should straighten out some of your misconceptions: http://www.skylighter.com/fireworks/how-to-make/Hand-Mixed-Black-Powder.asp

[patsroom]

From PyroGuide

 

 

Pulverone is ball milled black powder that has been slightly moistened so that it just clings together and pressed through a fine screen (a window screen will work). The resultant granules are dried and used for a number of different tasks. While you can leave the black powder in the ball milled state for packing in tubes - it will be a fine dust and very hard to work with. Making pulverone out of it decreases the dust problem and actually makes the hotter powders useful as lift powders because of the air spaces between the grains.

And the only reason I know this is because I stole it off the internet. Hey but seriously check out the wayback machine for pyroguide.com it will tell you so much your head will explode, no really.

http://web.archive.o...title=Main_Page

You should be able to find all of the question there that you have ask here.

 

Seem to me that Shadowcat 1969 has a good start on your info but you can still look up the Category:Definitions on the way back machine.

Read the heck out of the link I posted for you and you will find a whole lot more too.

Edited July 29, 2013 by patsroom

[pyroman2498]

Pyroguide isn't full of the most "Safe" and/or "Reliable " information i would stay away from a lot of that information.

BTW ShadowCat - make sure you check the information before you post, pulverone isn't the powder that comes out of the mill, The powder that comes out of the ball mill is Meal, pulverone is Screened black powder ( Granulated BP )

​To granulate BP all you do is wet it to a dough like consistency and push it through a screen.

[TranslucentDragon]

Hahahahaha.... I think with the amount of different things I've heard from this post I will definitely be looking at all the links and going through this forum. Well... there goes my monday . I guess if i have any further questions I'll just post 'em here.

[bob]

Isn't meal really 100 mesh and finer dust made from breaking up pucks of corned black powder, and mill dust is the stuff right out of a mill run.

@pyroman mind saying what you found on pyroguide that was unsafe.

[patsroom]

Pyroguide is an online pyrotechnic knowledge base which anyone can edit. The aim is to provide the novice to professional or people with just a general interest with a tool which can be used as a comprehensive guide to pyrotechnics, it's chemicals, general safety, tutorials and much more. With more than 539 articles and growing each day the potential of Pyroguide is very exciting. So get on board and share your knowledge.

From Pyroguide itself.

And as any open and free source you must be careful but there are alot of infomation on pyroguide that can introduce the basics of making fireworks. For someone working by himself it is his responsibly to insure a safe method of doing fireworks and to determine if the instructions recieved are correct or not. One must read as much on the subject as he can. Acquiring the information not just from one place unless it is a reputable source..................................Pat

[Shadowcat1969]

Pyroguide isn't full of the most "Safe" and/or "Reliable " information i would stay away from a lot of that information.

The powder that comes out of the ball mill is Meal, pulverone is Screened black powder ( Granulated BP ) [/color][/font]

​To granulate BP all you do is wet it to a dough like consistency and push it through a screen.

 

My understanding is that some BP terms are somewhat murky, including Pulverone and Meal. You can find different definitions in different places. As long as the two people speaking are in agreement on what is being referred to, they would be ok.

 

For instance, by your own advice to check your information: according to Skylighter's charts, Meal is defined as -40 +50 mesh (or finer, they use "Meal", "fine meal" and "X-fine Meal" processed powder, whether processed using pressing and corning or wetting and granulating. http://www.skylighter.com/fireworks/help/Black_Powder_Size_Charts.asp#grain What comes out of the mill, would NOT be Pulverone (as you pointed out), or Meal, but Mill Dust

 

That being said, I have also seen several posts, on more than one site, stating that some terms are somewhat interchangeable depending on exactly who you are speaking to. Like Pulverone. I have seen what I think of as Green Mix referred to as Pulverone, as well as processed powders.

[Mumbles]

Pyroguide has gotten better over the years. I know I've been critical of it in the past. It has had it's fair share of incorrect or misleading information on it, but to it's credit has been improving. Regardless, there is no one absolute source of knowledge in this hobby. Any information should also probably be vetted and cross checked by anyone reading it. I will never trust any one single source, though some are better than others.

I think this thread illustrates one of the issues when trying to discuss this topic. There is a lot of overlapping and confusing terminology on this particular subject. There have been very good posts made to this forum on this subject, but I honestly don't recall where exactly. I included my thoughts on the subject. A lot of this has already been said or linked to, but I find it easier to write out my complete thoughts on a subject so I don't miss anything.

To try to wrap my head around this subject, I think of BP in terms of two parameters. The state of processing, and the state of granulation. I divide the state of processing into milled and unmilled, and divide the state of granulation into granulated and ungranulated. This gives a total of four general states of BP.

Unmilled and un-granulated - This is generally referred to as "green meal" or "scratch mix", or if it is to be immediately milled a "mill charge". The three component chemicals have usually been screened together and often contain a binder. On it's own, it's used to prime stars.

Unmilled and granulated - Many veterans of cylinder shell building will refer to this as "polverone" or "pulverone" or "rough powder". The term polverone literally means coarse or large powder. The term polverone does refer to something that is granulated, but is often confusingly used to refer to both a milled and unmilled product by different groups of people. The unmilled variety is often used as a flammable filler when making cylinder shells. Despite what the skylighter link that pyrokid supplied says, I'm not very familiar with it being used as the entirety of the burst in shells. There is still usually a core of a milled powder.

Milled and ungranulated - This is typically referred to as mill dust or meal powder. Meal D is not the same thing as meal powder, even if they can be used interchangeably in some applications. This product can be used for some applications such as priming stars, as a component of some star/comet mixes, coating onto carriers for ball shell burst, making pressed inserts/spolettes, etc. For many of these, I personally prefer to use something more like meal D, which has less dust issues.

Milled and granulated - This will have all sorts of sub-classifications based on granule size and how it was formed. This will be your primary product used for lifting shells, and as a burst in cylinder shells and sometimes small ball shells. Some will make a distinction between milled powder that has been screen granulated and milled powder that has been pressed and corned or broken up. Some will argue that pressed and corned is the only product that can accurately be called black powder. Both granulated and corned can be used for similar purposes and are interchangeable in most instances. This product also forms the basis for many inserts, spolettes, stars, comets, some rockets, fountains, etc. It's difficult to make most pyrotechnics without this product in one form or another.

As far as the granulations go, this is where the "F" scale comes in. The more F's, the finer it is. The number of F's is also sometimes abbreviated simply by a preceding number. IE FFFFA = 4FA. After the F, will come the type of powder it is. Generally you'll see the FA's, FB's, and Fg's A type powder is a potassium nitrate based blasting powder, B type powder is a sodium nitrate based blasting powder, and g type powder is often glazed and used as a sporting powder in firearms and reloading. They do differ by more than just their particle size, however the differences really don't affect their use in pyrotechnics, so they're rarely considered. This is a pretty good writeup on the basic process and some of the differences if you're interested: http://home.comcast....aqs/bptypes.htm

[TranslucentDragon]

I'm still slightly confused on granulating. From what I understand: Granulating is putting a "finished" composition through a screen with a large mesh to separate it, as opposed to screening which is putting unmixed chemicals into a screen to better mix them. Is this correct, and if not: what are granulating and screening? Is the purpose of granulating to make a composition finer? If so: why not use a ball mill? Edited August 16, 2013 by TranslucentDragon

[TYRONEEZEKIEL]

Translucent, I am very glad you have proper interest in learning about making quality black powder. I'll happily explain granulating.

 

So after your Black powder has been ball milled completely, you sift the milling media out of it and you are left with meal. This is no longer green mix, and it is not yet pulverone. Black powder in the meal form is called a finished product, although it is technically still useless at this point. (except maybe as a prime) The reason it is called a "finished product" is that it is the form of black powder that you use to make various things (i.e. Lift, burst, black match, rocket fuel) Granulating black powder into pulverone will give you a final, complete, or otherwise finished form of black powder. This is done by taking your meal powder, adding 3-5% dextrin and introducing just enough moisture to have it stick together. You dont want to have a dough ball. It needs to be dry enough that no water can be squeezed out of it, but wet enough that it will just stick together into a clump. From here, you take your wetted meal and run it through a 15 mesh or so screen onto a sheet of newspaper or bowl. This is very similar to grating a block of cheese. After this, take the pulverone out into the sun to dry for about a day, maybe two.

 

This product here is granulated black powder known as "pulverone." This is now used for lift powder for roman candles all the way up to 3" shells. It is also used as burst for shells up to 3" as well. The idea here is to make little "grains" of BP. These grains have a much higher surface area to burn as well as incorporating little pockets of air in between the grains. This allows the flame to travel through the powder much quicker, resulting in a much faster, more instantaneous, and powerful BP.

 

Black powder meal on its own has very, very little use in the pyro world. It is pretty fascinating how far it has to be processed to go from individual chems to final product. The thing that gets me, is black powder is really not powder at all when its finished. I hope this helps some.

[TYRONEEZEKIEL]

Isn't meal really 100 mesh and finer dust made from breaking up pucks of corned black powder, and mill dust is the stuff right out of a mill run.

@pyroman mind saying what you found on pyroguide that was unsafe.

Do not be confused. This is usually referred to as "Meal-D." Denote the letter D. I am not sure what it stands for, but it is the fines that are too small for any kind of "F" grade of BP, so it is almost back to meal from the mill, but it is still slightly larger in particle size. Mill dust is the same as regular meal.

 

I think I may make a tutorial video with accompanying post to help define and clear up misconceptions about BP. It really does take quite some time to sort out all the terminology.

[TranslucentDragon]

@TYRONEEZEKIEL If you make a ball of dough with the black powder don't you get tiger tails as opposed to polverone? And so is there anything other than priming that meal is used for? And say I wanted to make black match or a rocket, would I use meal or polverone to make them? I'm confused because you said,"The reason it is called a "finished product" is that it is the form of black powder that you use to make various things (i.e. Lift, burst, black match, rocket fuel)." Are you saying that meal can be used to make these things, or that meal can be refined into a better form of black powder to make these things)?

[TYRONEEZEKIEL]

1. Tiger Tail is a completely different composition using the same components of black powder.

 

Tiger Tail Black powder

KNO3 44 75

Charcoal 44 15

Sulfur 6 10

Dextrin 6 +5%

 

2. You are very right. Meal powder is merely the starting point for whichever component you are making.

• Rockets can be pressed with meal powder
  
• You can make Black Match with a slurry using meal powder
  
• Pulverone is made from meal
  
• Corned BP is made from meal
  
• BP prime is made from meal
  

Think of it this way. You can use steel for countless applications. But it must be processed first. Iron ore has to be smelted, and some carbon must be introduced and then poured into ingots. These ingots can then be made into all sorts of things. Similarly, Black powder must be processed into meal before it can be useful anywhere else.

 

If you are in the states, feel free to call me. My name is Jarrod Frankum. I would be happy to help sort out your questions better. This goes for anyone who may have questions as well. Call me any time you'd like. I am a college student so I can talk just about whenever. 469-323-4783

[marks265]

A few things I would like to chime in on here.

 

Mumbles, you did a mighty fine job of explaining and without confusion.

 

Tyron... you added confusion

 

Mumbles, You should have added Meal D to your "Milled and granulated" subheading just to give it a home. This is one where people really get confused.

 

Tyron... there are a few formulas out there that use meal powder in the formula, it is more than "very little use in the pyro world" as you suggest. I won't be calling on you for your college expertise. I suggest you reread what Mumbles had written in the "Milled and Ungranulated" subheading. ( I pointed out the subheading so you wouldn't get confused again)

 

Cylinder shells of the Italian hand do use the canulle that has the rough powder outside of a column of milled and granulated powder of a certain target size based on the size of the shell. (as Mumbles pointed out) Cylinder shells of the Maltese hand (as I was taught) is a milled and granulated powder throughout the shell center. Unless the center is in use of course.

 

Meal D, because it has been processed is denser or heavier grained. Because it has been wetted, it will be more reactive and less dusty. I was taught to use it for spolettes. Maybe these are the reasons why, along with uniform sizing.

 

TranslucentDragon......stick to what Mumbles has said and then research or ask for your further needs when you start a specific task of a certain black powder. You did ask a very reasonable question. The words "Black Powder" have and always will be thrown around loosely. I think Mumbles post is the best I have seen in a single explanation yet. Mind you this is still a short version as tomes can be written and has been written on the subject.

 

We must also know that granulating can easily be as large as 3 or 4 mesh without a bat of the eye lid. These larger grades or sizes of powder screened for cylinder shells are quite common.

 

Yea I had to put my referee jersey on for this one. Again Mumbles did a bang up job and it kind of irked me that it got twisted a tad.

 

Mark

[TranslucentDragon]

O... K... Now I'm back to: can you define granulating for me? Is what Tyron said correct about that? If so, are you supposed to do it before or after you mill the powder? And if the answer to THAT question is "after", then how do you have unmilled and granulated compositions?

Sorry for the weird train of thought but now I'm slightly confused on what info is correct.

 

Are granulating and screening the same thing?

 

And so if I were to put milled and granulated BP in a really fine screen I'd have FFF or FFFF BP?

[schroedinger]

Screening: You sift the chemicals of a composition together trough a screen, to incorporate them.

 

Granulating: You take your ready made composition and wet it until it sticks together slightly and force the dought through a screen to get granules.

 

Granulating is used to get a powder which has wholes between the granules, to pass fire faster through it, which results in a higher passingon of the fire and so in a faster burn

[marks265]

O... K... Now I'm back to: can you define granulating for me? Is what Tyron said correct about that? If so, are you supposed to do it before or after you mill the powder? And if the answer to THAT question is "after", then how do you have unmilled and granulated compositions?

Sorry for the weird train of thought but now I'm slightly confused on what info is correct.

 

Are granulating and screening the same thing?

 

And so if I were to put milled and granulated BP in a really fine screen I'd have FFF or FFFF BP?

 

What granulating does is it gives you granules of power. Screen size selection used to push the wetted black powder through will help to give you your target size of black powder wanted. Once the wetted black powder that was pushed through a screen dries it is screened/seived again to sort the granules to specific sizes such as 2FA or 4FA. SO granulated is to push wetted composition through a screen to distribute moisture and created granules of powder. When dried it is screened with several different mesh sizes to obtain the different size grains you desire. As an example I would granulate my powder and let it dry. Then I would screen the batch with a 5 mesh screen, anything thing that stays on the screen is one size. Everything that passes I would then screen with a 10 mesh and save whatever stays on it and so on until you get to your finest grade.

 

As far as milling goes. This step changes the reactivity of the powder. When milling the powder it is more reactive or burns faster. Using unmilled black powder to prime stars is desirable because it burns slower and stays lit longer when the stars are traveling at a high rate of speed. Using milled powder for priming stars increases the risk of the stars not igniting because it burns fast and may not light the star. This black powder prime will flash over the surface of the star and not light the star.

 

You can granulate both milled and unmilled powder to get different strengths. It all depends on the powder's intended purpose. Unmilled and granulated is explained by Mumbles above. Merely screen the correct chemicals together to create a well mixed composition of black powder. Usually need to pass the composition through a screen several times. Then wet it into a putty and push through a screen to granulate. Let it dry and screen again to size the particles.

[TranslucentDragon]

NEW QUESTIONS!!!

 

I'm guessing this has been gone over (actually, I'm almost sure of it) but how long do I need to mill charcoal in an unmodified Harbor Freight Rock Tumbler(Ball-Mill). I spent the last hour looking up various phrases and words in the search bar of APC and couldn't come up with anything relevant.

 

How long do I need to mill sulfur and KNO3 in a ball mill (separately, of course)? Both are powdered, so I'm wondering if I even need to put them in a ball mill before I mix them to make BP (and no, I don't know what mesh size they are).

 

I read that it took one hour to be milled when you're milling the ingredient in a ball-mill (then you screen them and do whatever you need to do). Is this true?

 

The charcoal listed up there^ are some planks that I had sitting around (yes, I know it won't be the best BP but this is my first batch so I'm not looking to go buy willow or oak) that I put into a can and cooked. Is this considered activated charcoal? If not, how do you make activated charcoal from charcoal?

Edited September 9, 2013 by TranslucentDragon

[pyrokid]

The charcoal you want for BP is the stuff straight out of the retort. You just have to crush it into pieces that can be broken down in the mill. Simply mixing the three ingredients will not give you fast powder. They must be milled together.

[TranslucentDragon]

Sorry for the confusion, but I meant that I was going to put them in a ball mill to mix them. I just need to know how long I need to mill everything seperately, and then together.

[pyrokid]

For the KNO3, anything equal to or smaller than table salt in size will be perfect. You might even be able to use coarser stuff. I'm sure your sulfur is fine. Charcoal can present problems, as some pieces don't always like to be ground to airfloat. Anything that passes a window screen is good enough in my experience. I don't know any numbers for harbor freight mills, unfortunately. You'll learn this with experience anyway.

[TranslucentDragon]

Well, I've been running if for 3-4 hours. Do you think that's long enough?

 

How exactly would I be able to classify it as airfloat? When does it reach that point?

[Bobosan]

Well, I've been running if for 3-4 hours. Do you think that's long enough?

 

How exactly would I be able to classify it as airfloat? When does it reach that point?

 

You'll know it's airfloat when you pop the top of your mill jar and release a black cloud of charcoal dust. Would be wise to wear a respirator or dust mask.

 

I mill prilled KNO3 for one hour by itself before mixing and milling into BP. My cooked Paulownia charcoal is also milled for no more than one hour by itself.