Is there safe a Way to Ball Mill BP INDOORS?

[Chuleo]

My Ball Mill will be finished soon, but I don't have the opportunity to make my pyro related stuff outside.

I don't have a shop, nor a garden where I could build one. Therefore I have to Ball Mill my chemicals in my basement.

At the moment I use commercial BP for lift and H3/KP for the break...but that is getting really expensive the bigger the shells get.

 

Is it possible to ball mill bp in addition of maybe 10% water?

[Adrenaline]

You could use the CIA-Method.

That means you mill the charcoal and the sulfur without the KNO₃ .

Than you dissolve your Nitrate in boiling water, add the milled C and S and precipitate the KNO₃ with ice cold ethanol.

This process makes a very fast powder, and you don´ t have to mill any explosive composition, however it is labour-intensive.

 

Here´s an exact instruction on how to make BP with the CIA Method.

Edited February 27, 2011 by Adrenaline

[TrueBluePyro]

You could ball mill the black powder in a wet state. That is the first way I ball milled my first batch of black powder and I got some pretty decent black powder from it, I added way to much water, but its good cause, once it has finished ball milling, all you gotta do is scoop it out and 'rice' it and then let it dry.

 

I'm pretty sure it is safe to say that black powder will not ignite if it is wet.

[50AE]

Or you can mill all ingredients separately and the homogenize them in the mill for 5 minutes. This is what I do. Or if you are nervous about the final mixing, you can screen the powder using fine screens.

Milling wet wasn't a method for me. Adding little water and the powder will clump. Adding too much and the nitrate will dissolve and recrystallize, resulting in crappy BP.

CIA method is laborious and expensive, this is my opinion.

[Chuleo]

Thank you for your advice!

 

I once tried the CIA Method with H3... it wasn't only labour intense but also extremely messy. I definitely won't do that again.

 

I think I try the wet ball milling method. My jar has a diameter of 200mm and it will do a 2kg batch in one run. I think is unlikely for the bp to stick to the media since it is a fairly big jar with heavy media.

Do you know how much water I should add? 5-7% or even more?

[TheSidewinder]

NO! There is NO "safe way to Ball Mill BP INDOORS". Period, end of story.

 

You can minimize risk, but you cannot eliminate it.

 

And Mumbles might pitch in here to verify the percentages, but BP with a few percent water is actually MORE prone to ignite than bone-dry BP.

[NightHawkInLight]

NO! There is NO "safe way to Ball Mill BP INDOORS". Period, end of story.

 

You can minimize risk, but you cannot eliminate it.

 

Seconded! I can't believe how far this thread has gotten without that being said.

 

The only good idea I have seen posted so far is to mill the chemicals separately, but then they should ONLY be combined outdoors! It is very foolish to build fireworks in the same building where people live. There are plenty of people who have had accidents, both minor and severe, who can attest to that.

Edited February 27, 2011 by NightHawkInLight

[Chuleo]

Convinced.

[KruseMissile]

I've heard of milling charcoal and sulfur together, then add the potassium nitrate at the end for an hour or so. But as others have said, its not bulletproof. There will always be a chance... Prepare for the worst, hope for the best.

[Chuleo]

Im going to mill the sulfur/charcoal and the potassium nitrate separately, then screen it together outside and then proceed as described here: http://www.skylighter.com/skylighter_info_pages/article.asp?Item=115#BP That way i won't get super hot bp but it's the best way for me to get acceptable bp.

[NightHawkInLight]

Im going to mill the sulfur/charcoal and the potassium nitrate separately, then screen it together outside and then proceed as described here: http://www.skylighter.com/skylighter_info_pages/article.asp?Item=115#BP That way i won't get super hot bp but it's the best way for me to get acceptable bp.

Good plan. That should work fine for you.

[Mumbles]

Remember one important thing. Even if your BP isn't the hottest on the face of the earth, there is nothing stopping you from using a little extra to lift your shells.

 

I can surely attest to the kind of damage that 2 kilos of BP can do. I assure you that it is quite extensive and expensive.

[Fly]

Call me crazy! but I mill all together & have aways done it that way.Maybe I,m lucky,but with lead media & a plastic jar I don't see it sparking.Its heat that sets

off BP.But thats me.

Fly

[Chuleo]

Yeah many people do, but probably not a 2kilo batch in the basement.

 

Btw. Has anybody ever tried the Double&Double-method described here? http://www.pyroguide...der_Manufacture

It seems pretty acceptable.

Edited February 28, 2011 by Chuleo

[Mumbles]

You may want to try both and let us know. I recall hearing some people experimenting with it, but never heard much in the way of results. If you have slightly sticky KNO3, a bit of charcoal really helps to keep it free flowing and from clumping in the mill. That is about all I can tell you about the method. There may be some advantage to it, but you never know until you compare them back to back.

[50AE]

I use to mill the KNO3/S mix in advance. Then I mill a big batch of charcoal separately and finally, I weight and mix the three in order to make 300g batches. I use the 74:12:14 ratio, so per 258g KNO3/S mix I add 42g charcoal, I screen all two times and I put the mix in the mill for 5 hours to break any smaller KNO3 lumps. It's not a good idea to put everything unscreened when there are lumps of KNO3/S, because sometimes these tend to not break , but directly cake on the drum's walls.

I like this method, especially when I'm out of charcoal, because I can mill and accumulate much of the KNO3/S mix, saving myself time. Charcoal alone mills very fast.

Edited February 28, 2011 by 50AE

[MadMax]

Here's my observation so far. The reason it works best I think to mill all 3 together is because the KNO3 acts as a "milling aid" for the other ingredients (especially the sulfur which is a pain in the ass to mill). So splitting it may make sense to split the KNO3 in half and use each half with the S and C and then add them together after the fact.

 

I have ball milled in doors it's no big deal really. I just flooded the container with water that was already saturated with KNO3 at room temp so no more could be dissolved and recrystallized. My jar was about 1/4 full with comp and just barely submerged under water. It should be kind of like runny mud. I added a few larger lead media to compensate for the difference in specific gravity of the lead under water. Then at the end I let it settle for a few minutes and poured off the KNO3 saturated water and spread it out on some newspaper screening it occasionally to speed up drying.

 

I don't do it that way anymore because it's messy but it worked fairly well considering.

[Mumbles]

The issue I think you're going to run into with that is that the water will heat up from the mechanical action from the balls and ball milling. You will be dissolving KNO3, and it will be reprecipitating upon cooling negating some of the work that ball milling just did.

[MadMax]

I had thought about that too but what might make sense is to do a trial run and evaluate the temp after an hour or so and adjust as needed. Another advantage I think would that the charcoal has the KNO3 saturated water completely mashed into it repeatedly ensuring it gets completely filled. Similar to the gains with the CIA method but probably better due to the extended mashing in solution. One could always dry mill it afterward to finish it off.

 

The best BP I ever made ironically came just when I started to get into pyro a few years back and wanted to see just how good it could get. It went something like this...

 

I dry milled for 3 hours starting in the morning.

Then added water until it got to the consistency of soup and simmer it on the stove being careful to ensure it doesn't dry out on the bottom.

Then I added the hot semi-liquid ingredients back to the ball mill and milled that for 3 more hours allowing it to cool while it milled.

I then took out the resulting mud and let it dry in the sun on some sheets of Al foil.

Once it had dried I stuck it back in the ball mill and milled it for another hour.

 

The result was an impressive fast burning flowing powder. It made blackmatch that burned about 4 times as fast as the stuff they put in those flat 5-strand commercial quickmatch fuses. It was weird - it looked like the flame was crawling down the string.

 

It's a lot of work but I did it more for experimentational reasons. Add a little of this to slow burning BP meal and it probably averages it out pretty nicely.