Screened black powder for lift.

[SignalKanboom]

I am trying to build a ball mill with repurposed parts. Would an hope bucket be safe for mill jar that will only contain black powder? If not can a screened black powder be made adequately to lift shells?

Hdpe bucket*

[rogeryermaw]

with good quality chems INDIVIDUALLY blade milled, screened, wet to a dry clay consistency and meshed from 6-12 you can get serviceable powder. you may have to use a touch extra but it can be done without a ball mill.

 

i like to use 70/30 isopropyl alcohol to wet mine but that is getting hard to find these days. you can use more liquid since only 30% of it is water and it makes the resulting powder more consistent ime.

Edited September 4, 2020 by rogeryermaw

[SignalKanboom]

Love the avatar pic! One of the best shows.

 

Is it feasible for a beginner to succeed the first try? I have a star roller/ball mill Im building, but it is a motor with a bucket attached to the shaft at a 45 degree angle. As a star roller Im not concerned, but closing it with a bucket lid and turning media and chems Im worried about static.

[Arthur]

You are much better advised to sort out the proper tools for each job and part, before you start to use ingredients. Be advised that messing with powder that's a bit(to a lot) slow destroys your confidence because nothing works like you expected.

 

A cheap ball mill can be found from Harbor Fright or other hardware shops, or from the pottery hobby stores. It will be slow so don't wait for the powder.

[SignalKanboom]

Solid advice! Is the ball mill from harbor freight reliable? I have heard it goes out pretty quick.

[Bourbon]

I love my little HF tumbler. It's cheap. Treat it like it's cheap. Stay away from making it grunt.

 

When you have it apart, polish the bearing surfaces like a mirror (it's worth it). Mine hasn't broken down yet.

 

I run both jars but I only run 100, 50 cal leads in each jar and no more than 100 grams of comp in each jar. I get what I'm looking for in 4 hours constantly every time.

 

This article is great https://www.skylighter.com/blogs/how-to-make-fireworks/quick-easy-black-powder-ball-mill.

[rogeryermaw]

the bug bit me hard when i started. that thing couldn't make enough powder to feed my daily pyro fix, let alone build devices. if you're set on a mill, i'd suggest this:

 

https://fireworking.com/content/ball-milling-theory-and-practice-amateur-pyrotechnician

 

Lloyd wrote an excellent guide on milling and there is a good design for a mill in his book that, with minor adjustment can run two thumler octagon jars.

[Bourbon]

Yup, that's the way to go if you need a fair amount. I'm fine with 200 grams at a time. I don't get to use that much at a time anyway.

 

Sadly, fireworks are frowned upon here. Anything that leaves the ground is illegal. We aren't even allowed consumer firecrackers and the dirty dogs are talking about banning adult snaps. I have to pick and choose my battles wisely. Thankfully the guys and gals turn a blind eye for me at the rifle range.

[Richtee]

Thankfully the guys and gals turn a blind eye for me at the rifle range.

‘Till you start making mortars outta spent casings..

 

You can lift with the screened, but it’s no where near as good as milled/corned.

[Mumbles]

Most HDPE buckets are fairly large for a mill jar when starting out. A very common method is to make jars out of PVC pipe and a few fittings. It's a design popularized by Lloyd Sponnenburgh in the linked book above. You can see the basic design here: http://wichitabuggywhip.com/fireworks/misc.html#ballmill You may need to scroll down a touch. 4" will be about the same size as the harbor freight ones, and is about a quart. I tended to overfill mine and run it longer, but could make 200g of BP in about 6-8hr. 100-150g is closer to optimal. 6" x 9-10" long will be about a gallon in volume, and will make about 800-1000g per run. Those masses will depend on your charcoal to some degree. Very light fluffy charcoal, like balsa, will be lower, but denser charcoal could be more.

 

The harbor freight ones definitely work. I basically ran mine into the ground and it kept on chugging. You probably will need to replace the belt from time to time and occasionally add some oil to the rollers, but mine was surprisingly robust. The jars are nice since they're quieter that PVC, and the slight give helps to prevent caking a little bit. You can buy replacement jars as well if you just want to go that route. You may need to find the Lortone ones for replacements. In stock configuration, they will probably take longer as they're slower that what is optimal. Some people will modify the driven roller by sliding a bigger piece of tubing over it to enlarge the diameter and thus increase the RPM of the jar.

 

I've seen a lot of things get used as mill jars. Thinner plastic jars, like food containers, even work but will wear out faster.

 

It's definitely feasible to make hot BP in your first go. Good quality charcoal is by far the most crucial part. Other than that, it's just figuring out the right loading and right mill times.

 

Making BP with just screened chemicals is certainly doable too. The secret here is very finely divided chemicals. This generally requires a mill itself for optimal performance. I was never able to get things sufficiently fine with just a coffee grinder or blender personally. I don't doubt that it could be done. If you're going this route, it might be best to get a fairly fine screen, like 100 mesh, just to ensure it's all well powdered.

[Arthur]

A cheap rock tumbler from a hardware supplier will last for years if you are careful and be fully functional and reliable. Get some half inch lead balls, as media. make reliable powder by working out a good method and using that method every time.

 

Buy a bigger mill only if you really need it.

[justvisiting]

Somebody should sell pre-milled potassium nitrate, rubbermakers sulfur, and pre-milled hot BP charcoal in the form of a kit, maybe with a screen thrown in. I bet they'd sell a lot.

[Bourbon]

‘Till you start making mortars outta spent casings..

 

 

Make no mistake. I'm going to try it! And it's your fault.

[Arthur]

"Somebody should sell pre-milled potassium nitrate, rubbermakers sulfur, and pre-milled hot BP charcoal in the form of a kit, maybe with a screen thrown in. I bet they'd sell a lot."

 

As near as you will get at the moment.

https://www.skylighter.com/collections/black-powder-kits. It's powder but not as fast as you'd like.

[SharkWhisperer]

Even Skylighter states that you'll need a mill if you're buying their overpriced kit for straight BP. And a coffee grinder if you're using their even more expensive and crummy red gum BP kit. You can bet that their airfloat charcoal will be the cause of much misery to you unless you're happy stopping at making fountains. You can get premilled KNO₃ and pretty finely powdered sulfur from Fireworks Cookbook, both for $3/pound, and probably elsewhere, but you'd be better off making your own charcoal, whether from untreated pine/spruce/fir 2x4s or better woods like ERC (pet bedding chips at Walmart), alder (shingles from HD) or willow. It's really not difficult or expensive, and only takes about an hour with a simple retort made from a paint can.

 

Check Agora--somebody was recently selling hot ERC charcoal and may have some left, though it was a bit pricey.

[Bourbon]

I get my premilled Nitrate and Sulfur from Fireworks Cookbook like SharkWhisperer mentioned. I have no complaints, good stuff!

[justvisiting]

The belief that only 3 component milling can produce decent black powder is so entrenched that most minds will never be open to any other possibility, and that's unfortunate. Using Skylighter's kit would certainly not do anything to dispel that notion. I already know that screen-mixing can make powder that meets or exceeds the performance of commercial black powder because I've done it so many times, and tested it so many ways.

 

Skylighter's kit could be improved by:

 

1) Using a better charcoal for BP, like ERC or paulownia.

2) Milling the charcoal

3) Milling the potassium nitrate.

4) Changing the component ratio to maximize the fuel value of the charcoal.

 

Considering the importance of black powder to the fireworking craft, I think it's almost a bit insulting that Skylighter would present such a kit as something that can make black powder. The only guarantee is disappointment, IMO. I know everybody has to start somewhere, but Skylighter's BP kit offering seems designed to sell mills, not satisfaction

 

Fireworks Cook book is most of the way there. Pre-milled charcoal is something they sell sometimes. I've got some of their milled paulownia. It's good. I'll see if they like the idea of selling kits. Or maybe Woody would do it. Newbies could be better served, if decent screen-mixed BP kits were available. Providing a newbie the ability to make good BP right off the bat is like getting the PIN for their bank account. They will need a LOT of tooling to make use of the good BP!

[SharkWhisperer]

To the OP: JViz above has posted some excellent tutorials on making some kick-ass screen-mixed powder. Success seems dependent on the fineness of your starting materials--e.g., supermilled charcoal and nitrate. In short, you're going to find it difficult to make decent BP without locating a yet elusive source of supermilled ingredients, or you're going to need to shell out $50 for a cheapo mill from Harbor Freight (or make your own--also plenty of tutorials on the topic). I've had one for years that still works great for smaller batches (200g of BP seems to be right on the edge of "too much" per jar). Haven't broken a belt after hundreds of hours of use and occasional lubing of the spinning rod ends, and mine came with 4 or 5 extras. It's HF, so always a coin toss on ChiCom quality, but return policy is great if there's a local store near you. There are other options (Lortone) for hobbyist sized mills, or larger, if buying ready-to-go, but you'll pay for the upgrades. And there are many designs to build yourself from scraps and cheap components from Ebay and Home Depot.

 

Charcoal type is critical. The hardwood airfloat from Skylighter and FWC is great for some things (gerbs, blackmatch, slow primes, some stars, etc), but is simply insufficient, at least unless "supermilled" (takes us back to milling again), for making hot BP suitable for rockets and shells.

 

An inexpensive mill will make a huge difference in your enjoyment, and progress, in pyro. Especially because you can do so very much with good BP alone, and its derivatives. And it's one of your smaller pyro expenses when you start factoring in tooling sets, etc that will probably catch your attention in the near future.

[SignalKanboom]

Thanks for all the advice. I had a suitable motor, scrap wood and bar stock. I ordered pillow blocks and everything else needed to make the Wichita buggy whip ball mill. The motor is a huge dc motor with variable speed. I will go ahead and ball mill my powders. Im just using fireworks cookbook charcoal (air float). It says its pine, and the other wood that starts with a p thats good for hot bp. I have 10x10, 20x20, 40x40, 60x60, 100x100 mesh screens. I ordered just the screens from McMaster by looking at sky lighters screen kit sizes. I was surprised at how small the opening are on the screens. I thought 10 mesh was the right size for making 2fa, but I was surprised at how small 10 mesh openings are. 10 mesh is a .077 opening right?

[Arthur]

https://www.skylighter.com/blogs/fireworks-information/black-powder-grades-sizes-mesh

is a useful page.

2 - 50 mesh screens are useful for grading powder, 50 to 500 mesh screens may be of use for screening ingredients. Depending on where you live, gold panning screens come in many meshes and diameters and have a semi stacking frame.

 

Added

I'd still suggest a harbour freight mill! Initially you will make several batches of poor powder, it's better that the batches are small! When you are certain that your powder is fast enough then you could buy another HF mill or a bigger one. No-one can beat HF for price.

Remember that you will mill to dust then compact that to grains somehow. The hobby has uses for most grades from meal to 0FA . Once you have milled powder you have to either press and corn it, or damp it and grate it through a coarse screen to something of a useful grain size. Then you have to use a stack of meshes and grade the grain sizes. Different methods produce different proportions of each size cut, any waste can be repressed and corned again.

Edited September 7, 2020 by Arthur

[Arthur]

If you prep a mill and prep bags of weighed ingredients mixed, then running several mill loads a day is easy.

[BetICouldMake1]

Signal,

Since mesh size refers to the number of wires per inch the exact opening varies somewhat depending on wire thickness, but not enough to matter for our purposes.

 

If screen granulating BP typically a 3 or 4 mesh screen is used. Once dry the powder is classified by screening specific cuts like 2FA (-4+12), 4FA (-12+20). Trying to granulate through smaller screens is hard as they clog easily. I'd consider 8 mesh about the smallest practical size for that purpose. If you want more of the finer cuts it's easier to crush large grains once they are dry.

[Arthur]

If you intend to granulate a damp lump of compound then look for a cheese grater and just grate the slightly damp lump. It's easy to pick a size of grater to make larger or smaller grains. It's always best to get a good powder method then make some each of all the useful grades, remoistening and re grating anything that's the wrong size.

[SignalKanboom]

If you intend to granulate a damp lump of compound then look for a cheese grater and just grate the slightly damp lump. It's easy to pick a size of grater to make larger or smaller grains. It's always best to get a good powder method then make some each of all the useful grades, remoistening and re grating anything that's the wrong size.

That would be easier then framing a screen again.

[Mumbles]

If you find framing screens annoying, you can always melt them into the bottom of a cut off bucket. See here for example: http://bucketscreen.com/ John, the guy who runs it, is great too if you don't feel motivated enough and want to support a pyro friend of mine.