Pulverone (the type of BP)

[Mumbles]

I agree, it probably doesn't matter much. IBetICouldMake1 has a good suggestion. Coins are surprisingly accurately produced. I like to use a stack of say 5-10 coins. Any small variance averages out usually. A stack of 5 nickels usually weights almost exactly 25g, or 10 weighs almost exactly 50g.

 

To explain the difference, you may want to look at the resolution on your scale to start, and gather what it's telling you. Generally most scales are accurate to +/- 1ish unit of the last decimal, which also brings up a trick. Your scale has an absolute sensitivity, and by changing units you can get a more accurate number by virtue of choosing one with a better sensitivity. That +/- tends to go up a bit when you get to very fine resolution, but for you, that will be pretty accurate. You listed the weight at 2.0oz. This is +/- 0.1oz or 2.83g. To get an additional decimal, you'd have to be able to measure to +/- 0.283g. You also mentioned it's 57g which is +/- 1g. Those both make sense to me. The scale has a limit. To get 0.01oz precision, you probably need to be able to measure to 0.1g This means your charcoal reliably weighs between 2.1 (59.4g) and 1.9 oz (53.8g). I usually disregard any uncertainty, and assume it's between 2.049 (58.0g) and 1.950oz (55.2g). You can change units to try to get better accuracy, as you've noticed putting that trick into practice. Your charcoal also weighs between 58 and 56g based on what you said. Ignoring the uncertainty gives you 57.49-46.50g.

 

As a rule they teach you in chemistry labs, you optimally want your actual mass to be at least 100x the resolution of the scale for optimal accuracy. +/-1g is good for 100g or more, but 30g or so is usually fine. Thats 3% accuracy on the low end.

[MikeL]

 

As a rule they teach you in chemistry labs, you optimally want your actual mass to be at least 100x the resolution of the scale for optimal accuracy. +/-1g is good for 100g or more, but 30g or so is usually fine. Thats 3% accuracy on the low end.

This is where I got to. I'm measuring 100's of grams and fretting over a tenth of a gram when the measuring device accuracy is to the gram

[MikeL]

Ok... finally... I'm ready to post results of my first round of BP made with pecan wood charcoal and a lot of helpful advice. A couple of notes.

 

(1) If you screw up it'll be fine. In my case I think I rescued myself (with help) from my mistake. I was only off 90% on my KNO3 The test for this batch made the cutest little fizzle It took some weighing and digging into what I had vs what I should have gotten to figure it out. I won't know if I really figured it out until tomorrow. The mill is turning as I type.

 

(2) Pecan, once it's dried, likes its bark. It does not want to come off. At this point all of my BP was made with charcoal made from pecan with the bark on it. Sin of sins I know but don't judge yet. I just made a batch of charcoal from some pecan wood that wasn't quite as dry. Peeling it was like peeling a carrot. I hope to turn that into BP tomorrow.

 

(3) Don't mix batches... the best reason I have for that is that if you have a batch that's decently hot and you pour a batch of BP that you significantly shorted the amount of KNO3 on top of it... the first batch is screwed. In this case, I think it's recoverable. We'll see.

 

(4) The mill jar I have is pretty decent sized but it doesn't hold an infinite amount of chems Thankfully it was "just" close to too much.

 

There's probably more... but I think it's time to post the burn test. Yes... that is a water heater that I'm doing the test on Santa brings all kinds of things for us to play with.

 

I think pecan is viable. We'll see what it looks like with barkless pecan...

 

https://vimeo.com/495072869

Edited December 28, 2020 by MikeL

[SharkWhisperer]

Congrats on your first very excellent batch of BP !!!! That burn rate will allow you to build anything BP-based in hobby pyro!

 

Looks like ya got the kinks all worked out. Now aim for repeatability and consistency, and you'll be all set!

 

Great job & looking forward to seeing what comes next!!

[dlking59]

Looked fast and clean to me. Congratulations.

[Bourbon]

Nice!!

[MikeL]

I thought I would share a picture of my extrmemly expensive high tech retort. This is what I make my charcoal in:

 

 

Coffee came in the can. 4" diameter, 6" tall. Packed full of 3/4"-ish diameter pieces of wood, pull the grill off the BBQ pit, put the can in hole down, light two burners, wait for the smoke to stop. On average I get about 230g of charcoal for every run.

[SharkWhisperer]

Seems to be working just fine.

 

Eventually, it'll burn through so you'll be needing to drink a lil' more coffee, perhaps. Gallon paint cans are a little bigger but only last around 4-5 burns for me before they fall apart. I use a Behrens 6-gallon with "locking" (yeah, right) lid for now, but those, too only last so long.

 

In general, I like to move my cans around from time to time so all sides get approximately equal direct flame time, but that's always guesswork. I also cover my hole/lid attachment region with a wet towel when it comes off the flame to speed cooling and minimize possible oxygen entry and ash formation while cooling. But my lid started leaking after a few batches, so kinda necessary.

 

However you're doing it, it seems to be working well.

[MikeL]

It's got some pretty thin spots in it so it's not going to be around long. The place I got the coffee can with a metal lid from doesn't seem to have them now... I cover the hole when I pull mine off too. What I'd really like to get my hands on is a piece of 6" to 16" stainless steel pipe. I'd have to come up with some stainless steel plate to cap it and make the "lid" but it should last. And I'd have to learn to TIG stainless. I haven't taken the time to wander around our boneyard at work. We may have what I need. I've put one of those Behrens 6-gallon cans in the Amazon shopping cart more than once. I take it back out because shipping time is sketchy.

[Bourbon]

Did you find, right after gasification, it was perfect, Mike?

 

For everyone else: Been reading a ton and it sounds as if "over cooking", ash or not is bad. My way of thinking is, aside from, or just after releasing wood gas, to cover right then and there. We almost want the rest of the volatiles. Is this true? I'm trying to get the full understanding.

Edited December 29, 2020 by Bourbon

[SharkWhisperer]

Did you find, right after gasification, it was perfect, Mike?

 

For everyone else: Been reading a ton and it sounds as if "over cooking", ash or not is bad. My way of thinking is, aside from, or just after releasing wood gas, to cover right then and there. We almost want the rest of the volatiles. Is this true? I'm trying to get the full understanding.

You're probably going to get a lot of differing opinions on the topic of whether leftover volatiles in charcoal have potential fuel utility for BP. I cook til flammable gasses stop, and a little longer until remnant nonflammable whitish vapors (remnant water?) also stop and then I call it done and cool it pronto. Have gotten a uniform through-and-through char without a hint of white ash every time. Optimal? Dunno cuz never stopped earlier or did any side-by-side comparisons that purposefully left any volatiles in. Hot charcoal? Yup. Never had a bad batch yet (probably just jinxed myself).

 

So long as what you're doing is working for your purposes, all is well. If you want a little hotter lift, a little faster powder for endburners, etc., then you can tinker with your wood selection or how you cook it to heat it up just a bit more. Fast is fast. I like fast BP. But at a certain point, it seems you get to the "my dad can kick your dad's ass" stage, except you're mostly arguing with yourself which is always entertaining to watch. Once you can consistently make reliable and functional charcoal, and thus BP, you're pretty much golden and have the basic foundation necessary to progress on to more colorful/faster/louder/brighter/energetic/unique pyro stuff.

 

If you have sticks that aren't black all the way through, and they were relatively uniform in thickness before starting the cook, then you can be pretty sure you have some volatile compounds remaining in your charcoal--you'd probably be pulling un"charred" chunks of dry wood out of your mill or off your screens in that case. If so, does it work well for BP? Better than another batch of the same wood cooked more thoroughly? If your "outer rim" pieces in a retort are black throughout but uneven heating leaves centrally-situated pieces slightly undercharred, well, you're going to have some volatiles in the mix if you mill it all together. Will it be faster or slower? Dunno. Probably not difficult to set up a quick experiment to find out. But I'd rather spend that time trying out new comps than reinventing the wheel. Sometimes good enough actually is.

 

Charcoal speculation and hypotheses have been beaten near to death in past threads, but never concluded. Anybody have any new(ish) relevant observations or opinions to share?

Edited December 29, 2020 by SharkWhisperer

[Bourbon]

That's what I wasn't sure of. The way I took it, true "flammable" wood gasification only happens after the moisture has left, then the remaining volatiles go after. Several forums state, "pure" carbon sources make poor BP. That's what lead me to believe the remaining volatiles played an important part.

 

I make fantastic BP but, I buy my charcoal from the good folks around the forums. (Mostly cedar) So I kick myself all the time for not partaking in the making of my own.

 

I have some willow and aspen that I gathered tucked away out back, all nice dead, split, cut, and ready. I'm going to give this a go around April. I have a habit of over thinking.

[MikeL]

There's a lot of satisfaction that comes from making my own charcoal. I make mine pretty much like SharkWhisperer does. I look for the "jet", then check it to see if it's calmed down, if it's still smoking when I pull it off I let it cook a little longer, block the hole, let it cool. So far so good. The pecan doesn't seem to have a lot of ash. If you need an application to Overthinkers Anonymous I think I have an extra one

 

This is some of the wood that I've used.

 

One of the unpeeled pieces has a scrape mark on it (that I apparently didn't rotate into full view). That is what happens when the same knife that peeled the slightly green wood like a carrot is run across it a few times. The stuff is too hard too peel. Everything to date has been made with unpeeled pecan limbs. Slightly dry / not rotten in other words. You're looking at what goes into the can.

This is what happened when I undercooked and then milled the charcoal. The last few batches of charcoal have been crushed with 2# hammer rather than milled (I don't have that mill jar here).

 

[justvisiting]

It is amazing to me that black powder is really a subject in itself. It's not hard to make good BP, but it hard to know what to do, when there are so many different sources of information. I've been told that over-heating my retort will burn off the volatiles and wreck my BP, but I didn't read that until after I'd grossly over-heated my retort and made good black powder with that charcoal. I've been cognizant of the volatiles though, so I've been pulling my retorts off the heat before the smoke actually stops to try to retain them better.

 

I think the volatiles are responsible for the speed of the BP. I think the speed is the main thing that determines the power of the BP. People that talk about BP seem to be hesitant to conclude that fast powder does the most work, and that slower powder does less work. I don't know why this is. I made the above statement on a forum with experts in attendance, and was not shot down- or agreed with My conclusion came from trying to verify the claim that balsa charcoal burned quickly, but had poor 'gas production'. I found no evidence to support the claim, and no evidence that anybody has ever tested gas production of any charcoal. I don't think gas production is the only measure of the work that BP can do. Almost half of the combustion products are solids. I find that whenever I advance a new 'theory', based on assembling facts we know, the room goes kind of quiet. It's quite possible that us newer pyros annoy the gurus with our constant questions and ideas, so they just stop listening. A commonly held viewpoint is that there's nothing new under the sun, which I've always thought was a nonsensical collection of words. Maybe I just miss the meaning

 

I think it would be a good idea to use smaller pieces of wood in smaller retorts, to keep the cook time down.

[MikeL]

A simple, commonly cited, chemical equation for the combustion of black powder is:

2 KNO3 + S + 3 C → K2S + N2 + 3 CO2.
A balanced, but still simplified, equation is:

10 KNO3 + 3 S + 8 C → 2 K2CO3 + 3 K2SO4 + 6 CO2 + 5 N2.

The above is from Wikipedia. No volatiles in a basic combustion equation. When BP burns it makes a lot of CO2 and Nitrogen and a little Potassium Sulfate. Less than 1/2 of the mass goes to gas, the rest is solids.

 

But:

 

 

Components[edit]

Black powder is a granular mixture of

• a nitrate, typically potassium nitrate (KNO₃), which supplies oxygen for the reaction;
• charcoal, which provides carbon and other fuel for the reaction, simplified as carbon ©;
• sulfur (S), which, while also serving as a fuel, lowers the temperature required to ignite the mixture, thereby increasing the rate of combustion.

 

This seems to support that there is "other fuel" in the charcoal. It's just not accounted for in the equations.

Edited December 29, 2020 by MikeL

[Arthur]

There are lots of opinions, some supported by lab work, on the reaction of BP combustion, even some reports say that the pressure of the combustion reaction changes the end products. Davis, Shidlovski, Urbanskii etc all have things to say about BP and the making of suitable charcoal.

[SeaMonkey]

Ulrich Bretscher in Switzerland has done much research work with Black Powder.

 

These two pages offer some help in understanding the importance of Charcoal:

 

Charcoal

 

Homemade black powder

 

Some Charcoal manufacturers for use in Black Powder preferred their particular

variety of wood branches to be harvested in early Spring when the sap contained

the highest content of Sugars.

 

The freshly cut branches were de-barked then dried for up to two years before

charring to Charcoal at a specific temperature range.

Edited December 30, 2020 by SeaMonkey

[SharkWhisperer]

Ulrich Bretscher in Switzerland has done much research work with Black Powder.

 

These two pages offer some help in understanding the importance of Charcoal:

 

Charcoal

 

Homemade black powder

 

Some Charcoal manufacturers for use in Black Powder preferred their particular

variety of wood branches to be harvested in early Spring when the sap contained

the highest content of Sugars.

 

The freshly cut branches were de-barked then dried for up to two years before

charring to Charcoal at a specific temperature range.

Thanks. On his BP page, good ol' Ulrich seems to have cooked his charcoal to a little ashier white than I'd ever be happy with--I aim for zero visible ash. And his BP burn test of willow BP on the same page burned at only around an 8 or so on my subjective 1-10 scale (I expect a consistent 9 with willow).

 

So...though I appreciate his logic and explanations, I'm not really so impressed with his product, and it probably half boils down to that overcooked charcoal with a thick white outer layer of ash. The other half of his suboptimal burn rate (in my opinion) might be his mortar/pestle mixing method instead of ball milling.

 

10 minutes less time on the fire and an hour or two spinning in a mill, and I'm guessing his homemade willow BP would be much faster burning and looking really good.

[MikeL]

I put the pecan charcoal up against ERC (pyro baseball test)

I tried to post the table but this site hosed it up and made it unreadable

 

B Pecan is charcoal made with pecan with the barks left on

NB Pecan us charcoal made with pecan with the bark peeled off.

ERC is Well.. ERC that I bought from Fireworks cookbook. I made a trend:

https://www.dropbox.com/s/1j6yok7mkdt7mt8/Pyro%20Baseball.pdf?dl=0

I also tested some Meal D made from ERC. 8 grams gave me 9.2s. I stopped there

Edited March 15, 2021 by MikeL

[SharkWhisperer]

I put the pecan charcoal up against ERC (pyro baseball test)

I tried to post the table but this site hosed it up and made it unreadable

 

B Pecan is charcoal made with pecan with the barks left on

NB Pecan us charcoal made with pecan with the bark peeled off.

ERC is Well.. ERC that I bought from Fireworks cookbook. I made a trend:

https://www.dropbox.com/s/1j6yok7mkdt7mt8/Pyro%20Baseball.pdf?dl=0

I also tested some Meal D made from ERC. 8 grams gave me 9.2s. I stopped there

Nice powders. All worked nicely. Good enough performance for any fireworking purpose. And you're the first I recall to demonstrate great results with pecan, which is useful knowdedge! All things identical, would seem the pecan with bark is just a tad bit slower than peeled. Just for clarification, were these standardized in milling time, granulation method (if granulated?), and granule size for testing?

 

I cut/pasted your results pdf below, and it looks legible (for now). Good testing!

[MikeL]

Nice powders. All worked nicely. Good enough performance for any fireworking purpose. And you're the first I recall to demonstrate great results with pecan, which is useful knowledge!

 

All things identical, would seem the pecan with bark is just a tad bit slower than peeled.

 

Just for clarification,

were these standardized

 

in milling time,

 

granulation method (if granulated?),

 

and granule size for testing?

 

 

Milling time - 4 hours. I'll try 3 next time. I used 3 hours on a mix for making blackmatch (haven't tried that yet) and that looked as good as if I had milled for 4 hours

 

Granulation method / size - Wet with 70/30 isopropyl. Roll to 3/16" thick patty, press through an 8 mesh screen, dry, sort through an 8 mesh screen so 12 mesh screen for -8 + 12

[SharkWhisperer]

 

Milling time - 4 hours. I'll try 3 next time. I used 3 hours on a mix for making blackmatch (haven't tried that yet) and that looked as good as if I had milled for 4 hours

 

Granulation method / size - Wet with 70/30 isopropyl. Roll to 3/16" thick patty, press through an 8 mesh screen, dry, sort through an 8 mesh screen so 12 mesh screen for -8 + 12

Any binder employed? That's common for lift/burst where you want granules to remain intact and not crushed by the shell (lift) or by handling/compression during building (burst)? But for smaller shells especially, those risks are lessened and you can often get sufficiently hard granules without binder. Good size selection for launching tennis balls.

 

Perhaps others do, but I usually don't bother milling (except charcoal) for making blackmatch. Can't hurt, for sure, but a lot of people (myself included) just screen mix BP (with binder--I use either 5% dextrin or some % of CMC--you want stiff match) for making blackmatch. The stuff's going to be wetted to a thin enough slurry that more KINO₃ will go into solution and recrystallize during drying than occurs with just making a BP putty for granulating, where you can imagine only a small fraction of the nitrate actually dissolves. Also, when using dextrin for a binder (whether granulating or making match), it takes a little time to guarantee good/uniform exposure to water that's needed to "activate" it for optimal binding. This is less of an issue with BM because you're using a lot of water to begin with, and drying times are typically longer (even though I use 70% IPA for making BM slurries, too). A common issue when making first batches of BM is that it takes a long time (several days often) to completely dry. You have a nice hard stick after a day or two, but it seems to burn like crap; generally it's because it's still damp inside, and the problem solves itself with a few more days of drying. If you're adding dextrin to your BP for granulating lift/burst to hard granules, kneading the putty for a bit, or even just leaving it alone (covered so it doesn't dry out, or in a plastic bag) for 20-30 minutes after thorough mixing in your wetting solution, also helps give the dextrin some leeway/time to fully be wetted/activated and ultimately will result in harder granules.

 

Good controlled experimenting you've done with well-matched milling, formulation, granulation, and sizing techniques. Apples-to-apples comparisons, as is necessary.

 

Hopefully moistening times and drying conditions were pretty similar between batches, too. Anyways, nice BP.

[MikeL]

5% Dextrin. The grains are extremely hard. Like little rocks.

 

By throwing the match BP in the mill I was able to do other things while it churned away. I'm going to use the old school method of making match and wet it with Argo starch.

 

Ironically I put off making black match until I got to TX. It's easier for me to come up with the physical space to dry it. However... humidity is close to 100% and it's been overcast and misty. If it doesn't clear soon then I'll have to figure out a way to dry it in NM. Typically "clearing" involves a cold front and rain.

 

I'm afraid that building a drying rack is going to be in my future. Lumber ain't cheap... As far as drying goes, after a day or two I'll roll it into a coil on a bucket or something and put the coil in the drying box for a few days.

I followed the same process for making it and drying was timed to the minute Relative humidity and ambient temperature didn't swing a lot so that all went well.

[SharkWhisperer]

5% Dextrin. The grains are extremely hard. Like little rocks.

 

By throwing the match BP in the mill I was able to do other things while it churned away. I'm going to use the old school method of making match and wet it with Argo starch.

 

Ironically I put off making black match until I got to TX. It's easier for me to come up with the physical space to dry it. However... humidity is close to 100% and it's been overcast and misty. If it doesn't clear soon then I'll have to figure out a way to dry it in NM. Typically "clearing" involves a cold front and rain.

 

I'm afraid that building a drying rack is going to be in my future. Lumber ain't cheap... As far as drying goes, after a day or two I'll roll it into a coil on a bucket or something and put the coil in the drying box for a few days.

 

I followed the same process for making it and drying was timed to the minute Relative humidity and ambient temperature didn't swing a lot so that all went well.

Argo's inexpensive stuff (so's homemade dextrin from Argo:). You've probably seen Ned Gorski's video (looooong...) on the Argo method he borrowed from (??) (in addition to his Fireworking 101 video on usual BM manufacture with the usual slurry)? Hard stuff to screw up apart from patience in drying. If you're only making smaller batches, it's easy to dry just by winding it around brads/nails on either end of a 2x6 or similar cut to 5-6 feet. Most of my match is cut to 3-foot lengths for easy storage in mailing tubes (wrapped in foil, with silica desiccant packets). Preferable to me than storing in coils. Never had a problem drying match in the sun in super humid S Florida--just took a little longer. And please take your time completely penetrating all fibers of your string--if you see a white or even dark grey center when you cut your match, then you got insufficient impregnation and suboptimal match. I add a little Al to some batches to add a little heat to the burn, too. Never had a noticeable Al/nitrate/water reaction occur.

 

The only thing I add 5% dextrin to is some charcoal stars that are otherwise super delicate. For lift/burst BP and match, I usually top out at 2.5% max, allowing sufficient time for wetting, and get rock-hard granules and stiff match without affecting the burn too much (dextrin/starch is a fuel, just not a hot fuel). But everybody does things differently; that it works to your expectations is the only "requirement".

[Mumbles]

I'd consider the Argo binder more of a modified homemade wheat paste than dextrin. I don't know if anyone really knows where the method originated, but I suspect it's probably at least 80-100 years old if not more. It's been well known and talked about at least as a method practiced in the hey-day of domestic manufacturing as long as I've been in the hobby.