Safest way to make black powder?

[SamGurdus]

Where I live, you can't really buy black powder. I have heard the black powder created by ball milling is superior to that made with red gum. I am planning to buy a 6 lb rock tumbler from HF and modify it a little. I live in a neighborhood, so I don't have that much room to distance the mill from buildings, and want to be safe. I have heard you can mill it wet, does anyone have any information on this technique?

[dagabu]

First of all, if your ball mill exploded in a neighborhood, you are going to jail! The only "safe" way is to "hypermill" each ingredient (dextrin with the charcoal) separately and then combine them to premeasured water to make a putty ball and screen it to make the grains. Dry and sort by mesh size.

 

Don't take chances, don't break the law.

[NeighborJ]

Agreed, you will need a safe place to mill rather than a safer process. I can also say that I've experimented quite a lot with the wet mill process. It involves the use of volitile solvents which end up extracting the needed volitiles from the charcoal. It does make milling chems to a sub micron particle size possible but BP for some reason does not work. It clumps into a large ball and no milling takes place.

 

The normal rubber lined jars are no good for the solvents required and leech chems into your comp or the jar itself breaks down. There are solutions but there are other issues to overcome. Lead media cannot be used because of excess wear.

 

In the end, I found wet milling to only be beneficial for a few very specific aplications and non of those can be applied very well to pyro.

[SamGurdus]

First of all, if your ball mill exploded in a neighborhood, you are going to jail! The only "safe" way is to "hypermill" each ingredient (dextrin with the charcoal) separately and then combine them to premeasured water to make a putty ball and screen it to make the grains. Dry and sort by mesh size.

 

Don't take chances, don't break the law.

Do you know anything about using red gum instead of dextrin? Does it make a better powder? Skylighter's kit comes with these instructions. https://www.skylighter.com/blogs/how-to-make-fireworks/red-gum-black-powder

[stix]

Do you know anything about using red gum instead of dextrin? Does it make a better powder? Skylighter's kit comes with these instructions. https://www.skylighter.com/blogs/how-to-make-fireworks/red-gum-black-powder

 

I don't know if it makes "better" bp (as in performs better), but it certainly would be more expensive, and with all those alcohol fumes probably not any safer. Dagabu's method posted above would probably suit your requirements.

Edited November 16, 2018 by stix

[dagabu]

Stix,the red gum and dextrin are simple binders that hold the BP together in grains so you can classify them. Edited November 16, 2018 by dagabu

[SamGurdus]

First of all, if your ball mill exploded in a neighborhood, you are going to jail! The only "safe" way is to "hypermill" each ingredient (dextrin with the charcoal) separately and then combine them to premeasured water to make a putty ball and screen it to make the grains. Dry and sort by mesh size.

 

Don't take chances, don't break the law.

Would this process be suitable for making lift and burst? Sorry for the late reply.

[dagabu]

Yes, it does work as long as your charcoal is reactive enough to make good black powder.

[SamGurdus]

Yes, it does work as long as your charcoal is reactive enough to make good black powder.

Glad to hear that, I was getting worried after ordering like $100 of chemicals. I got willow charcoal crumbles, so I guess I'm good.

[Arthur]

Once you have a ball of damp, milled ingredients, just damp enough to be glossy, then try every available cheese grater and see what powder size they produce and what size range they produce. Also try some of the mesh screens that you have, some will make useful particle sizes.

 

Sieve your dried grains into useful size ranges and return anything left to the wet ball and re cut it.

 

It's important to have the ball of milled powder with exactly the right moisture content.

 

If (as!) the separate ingredients milling method is inferior, be very sure that you have good ingredients! Starting with the charcoal, use Willow or Alder charcoal if you buy it, If you make it add ERC pet bedding to the list of good woods, then Balsa and Vine.

[davidh]

Who did that big write-up with test results on milling individually and combining vs. milling together? It was an interesting read.

[davidh]

You can also take the components for a batch of black powder, and divide them into two parts, such that one part has most of the fuel (charcoal, sulfur), and the other part has most of the oxidizer (potassium nitrate). Then mill each part separately, and mix them after milling. This way each part is effectively a composition that is incapable of exploding (burn maybe, explode, no).

 

I hear some people mill whistle mix in this manner.

 

If you do this, the tricky part is making sure each part properly fills a mill jar. You may end up having to make too much of one part to have enough of the other part to fill the jar.

[davidh]

Where are you anyway? You should consider joining a regional pyro guild/club. My observation has been that there are pyros all over the place that will gladly let you come to their place and let you work on your projects. The downside to that is they may talk you into helping them with their projects too. (Hint - don't let them teach you how to make lances) :-)

[Mixer]

Who did that big write-up with test results on milling individually and combining vs. milling together? It was an interesting read.

Ian Von Maltitz

Black Powder Manufacturing Testing and Optimizing.

ISBN 0-929931-21-1

Edited December 16, 2018 by Mixer

[Mumbles]

The other you may be thinking of DavidF.

 

 

https://www.amateurpyro.com/forums/topic/12403-3-component-vs-individual-milling/?hl=supermilling

[davidh]

The other you may be thinking of DavidF.

 

 

https://www.amateurpyro.com/forums/topic/12403-3-component-vs-individual-milling/?hl=supermilling

That was the one. Thanks!

[stix]

Stix,the red gum and dextrin are simple binders that hold the BP together in grains so you can classify them.

 

Derrrrrr!!!

 

Yes, I do know the purpose of the binders. Dextrin with water and redgum with alcohol. I'm having some right now. Although redgum stuck between the teeth is not a good look.

 

Derrrrrrrrrrrgggghhhgggghhhh!!!!!!

 

Edited December 19, 2018 by stix

[dagabu]

Bad Stix! No eating the red gum, the paste either!

[Voryon]

I am using arabic gum to bind my BP, no need to use alcohol and it makes very strong granules after drying. Addition of 15g Arabic gum to 532g BP (my batch size) is fine and I see no negative effect on burn rate. For Red Gum I'm always concerned about impact on speed as it is added (even though in higher amounts) to slow down burn speed e.g. in delay slurry for "Beraq".

[dagabu]

NICE! What is your mix for the delay slurry for Beraq? I don't have that one.

[Voryon]

20% RG is a good place to start, it then depends on the speed of the pure BP where you end up, so some tweaking to get to the desired speed may be necessary. The RG tames fast BP into a nice "incense stick", that is even interesting to watch for the first Time.

[dagabu]

Very cool!

[DavidSvennigsen]

First of all, if your ball mill exploded in a neighborhood, you are going to jail! The only "safe" way is to "hypermill" each ingredient (dextrin with the charcoal) separately and then combine them to premeasured water to make a putty ball and screen it to make the grains. Dry and sort by mesh size.

 

Don't take chances, don't break the law.

Right, process can be followed. Thanks for this advice.

[SharkWhisperer]

Once you have a ball of damp, milled ingredients, just damp enough to be glossy, then try every available cheese grater and see what powder size they produce and what size range they produce. Also try some of the mesh screens that you have, some will make useful particle sizes.

 

Sieve your dried grains into useful size ranges and return anything left to the wet ball and re cut it.

 

It's important to have the ball of milled powder with exactly the right moisture content.

 

If (as!) the separate ingredients milling method is inferior, be very sure that you have good ingredients! Starting with the charcoal, use Willow or Alder charcoal if you buy it, If you make it add ERC pet bedding to the list of good woods, then Balsa and Vine.

And dry it as quickly as is reasonably possible--sunlight with a breeze (not on something that could potentially heat up to ignition temp) or in a dryer box using a shielded cheap ceramic heater from Walmart (dryer boxes are good for many things, and worthwhile to make one early). Slow drying risks allowing potassium nitrate to recrystallize as larger, less effective, less-incorporated crystals, and therefore slower powder. Though most prefer pure water for BP granulation, I prefer to use 70% isopropyl alcohol--the alcohol evaporates quickly, and there's less water (30% of added solution) to evaporate off; I find that this 30% is sufficient for activating the dextrin if I'm adding as a binder. But alcohol costs money and water not so much. Plus, with the encroaching coronavirus scare, at least in my area people are clearing off the shelves of isopropyl at Walmart as fast as they're stocking them, so there's that. And Amazon is currently charging extortionate rates for rubbing alcohol--the cheapest I saw today, for a single 32 oz bottle of 70%, was an unbelievable $14 (usually costs around $2 plus change at Walmart). Extortion. So there's that. But ceramic heaters are not in short supply!

 

Leave out the dextrin/binder if you're making rocket fuel. You don't need or want a binder in rocket fuel--it'll just slow burn rate--but binders are helpful for giving granules some mechanical strength for use as lift.

 

Some kitchen graters are too fine of mesh for reliably/reproducibly sized BP granules (for lift/burst), though not so important if you're just speeding up the burn rate and neatening it up for rocket fuel handling. Count the number of holes per inch to get the mesh--most BP I use for up to 4" shell lift/burst and rocket fuel are between 10 and 20 mesh. Screens are easy to locate if the kitchen supplies don't quite cut it--cannonfuse.com, for example, or McMaster. If possible, buy 1/8" hardware cloth from Home Depot (if in USA) or a local hardware store--it's getting rarer and you might have to special order it, but it makes great 8-mesh screens cheaply. I see the more usual 1/4" hardware cloth for sale everywhere, also cheap, but it makes comparatively huge grains--I use it for screen cutting stars, but it's too large for BP granulation for most of the projects I do (good for cannons, though, or perhaps huge mortars--bigger than mine).

 

Please don't mill complete BP mix in a populated area. And be careful as hell with everything pyro-related; BP granulating/drying/storage/use... What do you intend to do in a congested area??? Strongly suggest taking other's advice and locating a local established pyro, with a safe venue, who's willing to share. Pyro is already risky to the operator. If you, purposefully or not, place other people's health and safety at risk, then you are officially a complete twat--please don't be that guy.

[SharkWhisperer]

20% RG is a good place to start, it then depends on the speed of the pure BP where you end up, so some tweaking to get to the desired speed may be necessary. The RG tames fast BP into a nice "incense stick", that is even interesting to watch for the first Time.

What's the advantage to using expensive red gum to slow burn rate in a delay comp over, for example, sodium bicarbonate that's dirt cheap and will slow BP to whatever burn rate you wish?