Black Powder Problem

[maddyn99]

I have just finished my 3rd attempt at making black power and I am still not happy with the end result. Not sure what I am doing wrong maybe someone can point me in the right direction.

 

Chemicals I am using

 

Potassium Nitrate - Prilled from Skylighter 75%

Sulfur - From Pryodirect 15%

Charcoal - Airfloat from Skylighter 10%

Dextrin - from Skylighter + 1%

 

Ground in a homemade ball mill for a minimum of 4 hours, 3rd batch was probably 6 or 7 hours. Resulting mix is very very fine almost as fine as the airfloat charcoal.

Seems to burn fairly well. Leaves a black mark on paper without burning it, however i dont anywhere near the lift as i was getting from commercial grade 2f. not sure if this was normal.

 

Using commercial grade i was using anywhere from 4 to 5 grams to get a 2" 200' or so in the air. Tried the same thing with what I had made and it went maybe 50 or 60'. Is this normal? do i just need to use more since its homemade or am i doing something wrong here.

[pyrokid]

Black powder: 75 KNO3, 15 charcoal, 10 sulfur. I add 4% dextrin to my lift.

 

Your finished product out of the mill should be just as fine as the airfloat charcoal you started with. If you can see grains of any individual constituent, your mill isn't working properly or you're not milling it for long enough.

 

Homemade powder is as fast or faster than commercial powder. A good approximation for small shell lift is 10% of the shell's weight in powder.

 

Are you granulating it after it comes out of the mill?

[maddyn99]

Black powder: 75 KNO3, 15 charcoal, 10 sulfur. I add 4% dextrin to my lift.

 

Your finished product out of the mill should be just as fine as the airfloat charcoal you started with. If you can see grains of any individual constituent, your mill isn't working properly or you're not milling it for long enough.

 

Homemade powder is as fast or faster than commercial powder. A good approximation for small shell lift is 10% of the shell's weight in powder.

 

Are you granulating it after it comes out of the mill?

 

 

Yes i use a mix of 75% water 25% denatured alcohol and wet until the mixture is not quite clay like...not sure how to describe it any better.

 

I then put it through a kitchen type of strainer/sifter that is probably around a #10 or so, it gives me a granule that seems to be close to what the 2F was. I can get some pics if that would help?

[pyrokid]

Pictures aren't needed. I think you should fix your formula unless you just mistyped it. It really sounds like your milling isn't optimal, I think that is the cause of your problems.

 

Skylighter charcoal is known for being very average as well. You might try some hotter charcoal such as willow or pine.

Edited April 18, 2014 by pyrokid

[Jakenbake]

Are you using 10% sulfur or 15%?

[maddyn99]

Are you using 10% sulfur or 15%?

 

10% per this article

 

http://www.skylighter.com/fireworks/how-to-make/Black-Powder-Quick-and-Cheap.asp

[maddyn99]

Pictures aren't needed. I think you should fix your formula unless you just mistyped it. It really sounds like your milling isn't optimal, I think that is the cause of your problems.

 

Skylighter charcoal is known for being very average as well. You might try some hotter charcoal such as willow or pine.

 

Can i put it back into the ball mill and mill it further? its pretty dang fine powder but i have nothing to lose at this point, or should I just start over.

 

I am pretty much stuck with the 5lb of skylighter air float charcoal for now, I would either have to buy more or make some and neither is an option at this point.

Edited April 18, 2014 by maddyn99

[nater]

Is it fully dry to the point where it feels and sounds crispy?

 

You can try milling it again, or you can just use more to lift your shells to the proper height.

[Arthur]

Small mills usually take longer to mill powder. for 100g 12hrs in a mill is not unusual. Unless you use good charcoal you are never going to get good powder,- you need to know what type of tree it came from, Willow and Pine are known to be good, other woods are either good or bad, with poor wood you will never make faster than fountain comp

 

The three big problems with milling usually come down to, damp ingredients, poor charcoal, inadequate mill time.

[eb11]

Mad I use the chemicals from skylighler for my bp I don't have any issues the only thing I do different is I push mine through a 4 mesh screen then when dry I push it through I think a 10 mesh then I get my different sizes from that

[FlaMtnBkr]

It is your charcoal most likely. Skylighter airfloat does not make hot powder.

 

What is your mill? You can try throwing it back in the mill and letting it go over night a minimum of 15 hours, 24 would be even better. Then you will know how big a difference the milling makes. A big mill doesn't need those run times.

 

If you have a $20 bill you can make a TLUD and get a bale of eastern red cedar pet bedding and make a lot of really good charcoal. It's really easy to make too.

 

Edit: you can always use more of your powder until you get it dialed in.

Edited April 18, 2014 by FlaMtnBkr

[MWJ]

Did you granulate it?

[FlaMtnBkr]

 

 

Yes i use a mix of 75% water 25% denatured alcohol and wet until the mixture is not quite clay like...not sure how to describe it any better.

 

I then put it through a kitchen type of strainer/sifter that is probably around a #10 or so, it gives me a granule that seems to be close to what the 2F was. I can get some pics if that would help?

[BurritoBandito]

I'm going to agree that it is probably due to your mill. What is the inner diameter of your jar, how many RPMs is your motor running at, what is your grinding media and it's diameter, how much did your charge the mill with powder and media? I've noticed that with a smaller ball mill my results are best when I let it run until the BP cake to the walls, then I shake the jar to uncake it and let it run again. After doing this for solid day my BP is pretty damned milled. There is a huge difference between properly/inproperly milled BP. Personally, if I were you, I would throw it back in the mill for a day or so and then regranulate it.

[maddyn99]

Ok i waited another day to make sure the BP was dry. Total time of 3 days drying so I am fairly sure its dry and the same issue, so its probably not a moisture issue. My ball mill is home made. Here is a short video of it running EMPTY. not sure why but my camera is not working but the video works fine....go figure. Video is sideways sorry about that, but you get the idea.

 

https://www.youtube.com/watch?v=vuiO9FRlAdY

 

its a 4" X 6" Container with a 3" reducer so I can put on the cap. I am using lead shot as a milling media and its about 1/2 full. You can hear it on the video. Best guess is around 80 RPMs. I have about 3/4 of a kilo of BP meal left over, so I am going to run it for another 4 to 6 hours and see if that helps any. Or should I run it longer?

[maddyn99]

Ok i re-milled a small amount of BP meal for another 8 hours or so. I then ignited and compared a 1g sample of the two meals. The one that was milled longer was much more reactive that the one that I started with, so obviously I was under-milling my BP. So thanks for the suggestion on that. I started the full batch this morning around 7:30 am (about 7.5 hours) and just checked on it and this is the meal way came out of the container. Is this clumping normal or am I once again doing something wrong?

 

http://i67.photobucket.com/albums/h320/maddyn99/Projects/FireWorks/2014-04-20145919.jpg

Edited April 20, 2014 by maddyn99

[nater]

Yes, the clumping is normal. It can be mitigated by making sure your components are completely dry before milling. The likely culprit is the charcoal.

 

Some will dry each component seperately in a drying box before milling to prevent it. Myself, I don't worry about it, but I am not after the most reactive BP I can possibly make.

[TYRONEEZEKIEL]

As far as clumping goes, dry your kno3 first. I struggled with this for a long time. I put mine in an old rotisserie cooker for 30 minutes before milling. It makes a large difference.

 

Do not expect commercial results with commercial hardwood charcoal. I'd be happy to send you a sample of some fantastic black willow charcoal which really thumps. Also, lose the dextrin and try corning. Its not really much work and makes extremely consistent results.

[Shadowcat1969]

The next place you should look to go, after making sure all your chemicals are completely dry before milling, is: different charcoal.

 

I tried for quite a while to get good lift powder from Skylighter mixe airfloat, and I could lift a shell, but it took more B.P. than I liked. I bought some Paulownia charcoal and there is no comparison. I use something on the order of 1/3 as much B.P. for my lift.

 

There are several charcoals that are supposed to be good, you can find which ones in a lot of places both here on the forum and other sites. I am partial to the Paulownia because it works well for me, so I haven't tested others for myself.

 

I also agree with Tyrone, corning really works well for me to get consistent results.

[maddyn99]

As far as clumping goes, dry your kno3 first. I struggled with this for a long time. I put mine in an old rotisserie cooker for 30 minutes before milling. It makes a large difference.

 

Do not expect commercial results with commercial hardwood charcoal. I'd be happy to send you a sample of some fantastic black willow charcoal which really thumps. Also, lose the dextrin and try corning. Its not really much work and makes extremely consistent results.

 

Well im stuck with 5lbs of charcoal for now and its a ton, way more than I thought when I ordered it. What is corning?

 

And i thought the stars would be hardest part of making shells, Hah. So far its the black powder. Total of 14 hours milling so far just on this batch. Probably 30 hours total just trying to get the 1st batch even close.

Edited April 22, 2014 by maddyn99

[schroedinger]

Why don't you get some proper charcoal, and use your 5 lb for making charcoal streamer stars like TT, as they use quite a lot of charcoal

[Peret]

Skylighter airfloat makes really slow BP. I keep some around and use it for stars and rocket fuel because it may be slow, but it's very consistent. I make my BP with willow charcoal that I get from Custom Lump Charcoal, and paulownia, which can sometimes be got from Algenco. The willow is in sticks that need reducing to powder in a meat grinder, but Al supplies his ready ground.

 

I would also omit the dextrin and granulate with water only. Dextrin slows it down. The grains will be quite hard enough, and if there's a lot of dust left over you can just do it again, but there won't be much if you use enough water. I found wetting with water makes quite a difference, and have occasionally needed to granulate a batch a second time when I didn't make it wet enough the first time.

[Bobosan]

Just finished milling lump Willow from Customcharcoal. It is not soft like lump Paulownia charcoal and as Peret mentioned, needs to be ground down before milling to air float. I used a bucket and a 5lb hand sledge hammer to do this and still had some very hard pieces that refused to mill. Closer inspection showed those pieces to be uncooked. It's also quite heavy vs. Paulownia air float and not as voluminous as Paulownia.

[Peret]

Just finished milling lump Willow from Customcharcoal. It is not soft like lump Paulownia charcoal and as Peret mentioned, needs to be ground down before milling to air float. I used a bucket and a 5lb hand sledge hammer to do this and still had some very hard pieces that refused to mill. Closer inspection showed those pieces to be uncooked. It's also quite heavy vs. Paulownia air float and not as voluminous as Paulownia.

I used to hammer it, but the dust always got out and made me and my concrete floor black. I picked up an old hand meat grinder in a junk shop and that does the trick nicely, but it's slow.

 

The uncooked bits are a nuisance that I discovered when I first tried to ball mill BP without grinding the lumps first. I had to screen them out and weigh them, then replace with the same weight of good charcoal to keep the mixture the same.

 

Someone once gave me some balsa charcoal. It filled a fat gallon bag but only weighed about two ounces. I couldn't work with it because it was so bulky, so I don't know if it would have made good powder or not.

[FlareLauncher]

Pardon the newbie intrusion. Please let me see of I understand, are willow and pine the best candidates for cooking in a retort to make the best BP? Thanks!