Here is the write-up "My homemade black powder"

[3006guns]

Thank you! That's the kind of information I need. Just one question.....does the water have to be boiling or would just hot or cold work? (just trying to be thorough)

[lavenatti]

Guys, if you really want to make usable BP check out the following website:
http://www.wichitabuggywhip.com/fireworks/
Read the sections on Black Powder and Charcoal as a Variable (at a minimum).

I read some good and some not so good advise in this thread, it's not difficult to make BP faster than is available commercially but it has to be done correctly. The listed website will help with that.

[3006guns]

That's a very informative website..........thanks for posting!

After a decided failure with the alcohol method, I sat back and reflected on my methods vs. results.

The ordinary urine BP was simple to make and worked well, although a bit slow, and left bits of unburned sulphur. I suddenly realized that I wasn't really incorporating my ingredients all that well and further research bears that out. As a result I ordered a small, inexpensive rock tumbler in order to mill the ingredients (remotely!). Once everything is well pulverized and thoroughly mixed I'll experiment with both urine and a 50/50 water alcohol mix. I'm hoping the urine mix will be adequate therefore eliminating the additional cost of the alcohol, but we'll see.

The whole idea here is to produce small amounts of a propellant that is at least equal to the commercial powder, at a lower cost. It must be safe, stable, produce equal pressures and above all, smell like sulphur!

Update: after posting the above, I noticed my "ugly" alcohol powder had dried. It looked for all the world like very coarse grey sand, with little yellow speckles. Might as well see if it even ignites, so I put a small amount in a steel bowl and touched a match to it. Wow......despite everything going wrong during its manufacture, it took off much more quickly than my previous mixes. I attribute this to better incorporation and the alcohol precipitation. Once I've ball milled the ingredients, adding alcohol and some water as the wetting agents should do the trick. More to come in the next few days!

[lavenatti]

While it may seem like the right thing to do, wetting can be counterproductive and urine adds nothing but odor.

In a typical rock tumbler you'll want to fill it half way with your milling media - .50 cal hard lead balls will be fine, add 75 grams potassium nitrate, 15 grams of charcoal (use the proper charcoal) and 10 grams of sulfur. If you're using garden sulfur add 11 grams to make up for the clay binder they use to form it into little pellets.

It won't look like much in the container but more won't mill properly. Now run it for at least six hours. You should have a fine uniform powder with a slightly greenish cast to it.

Don't wet it.
Mix a solution of 9 parts hot water to one part dextrin (this method was developed by Eugene Yurek and I've seen it posted with fantastic results on several pyro sites) it will take some work to dissolve it all.
Now add 15% (by weight) of this solution to your powder and mix it in well, up to 20% can be added if necessary.
Now push the powder through a window screen onto a layer of newspaper to granulate it. Leave the layer thin to allow it to dry easily.

Give it a few hours to dry and test a little by lighting it on a piece of white paper. You should have a quick poof and there shouldn't be anything left on the paper but a stain.

By dissolving the dextrin in the water first there is not a lot of water left to dissolve your potassium nitrate. If the potassium nitrate dissolves it will form larger crystals as your powder drys. Larger crystals will cause it to burn slower, this is why wetting powder is not the best method for a fast powder.

The charcoal, if you've read the referenced website, is half the battle. Using a "fast" charcoal like Tree of Heaven or black willow will make all the difference in the final product. There are plenty of articles on making your own charcoal available on the web.

Commercially they would press the dry powder from the mill to a density of 1.7 grams per cubic centimeter. This forms it into a solid "puck". The pucks would then be broken up (corning) and seived to seperate the different sizes into 2F, 4F etc.
The powder may further be "polished" by tumbling with graphite.

[3006guns]

Sounds like an excellent, well thought out method. I was wondering about the loss of nitrates with the water and, of course, the answer is NOT to wash it away in the first place. I'll give it a try.

[lavenatti]

Great, I can't wait to hear about your results.

Be carefull with your grinding media, lead is fine but ball bearings and ceramic may spark so they are a no-no.
Occasional clumping may occur when milling. If you check your mill periodically you should see fluffy powder when you open it. If everything is clumped up try drying your saltpeter in the oven at 250 degrees F for a few hours and try again. Milling during cold weather seems to reduce the clumping problems. (you are milling outside aren't you?)
If everything clumps up after 4-6 hours it may just be finished.

Also, milling all the components seperately to a fine powder before mixing and milling together will reduce your final milling time a little and avoid lumps of charcoal in the final product.

[atom73]

Still learning from you guys about BP making. Happy to see that lots of folks are still here and safely experimenting. I must say I am very interested in trying the other process of ball milling and dextrin addition, Im not beholden to any technique in particular, just the best one. Thanks for all the input.
Mike

[3006guns]

Great, I can't wait to hear about your results.

Be carefull with your grinding media, lead is fine but ball bearings and ceramic may spark so they are a no-no.
Occasional clumping may occur when milling. If you check your mill periodically you should see fluffy powder when you open it. If everything is clumped up try drying your saltpeter in the oven at 250 degrees F for a few hours and try again. Milling during cold weather seems to reduce the clumping problems. (you are milling outside aren't you?)
If everything clumps up after 4-6 hours it may just be finished.

Also, milling all the components seperately to a fine powder before mixing and milling together will reduce your final milling time a little and avoid lumps of charcoal in the final product.

You mean ball bearings and chunks of flint won't work? Just a minute, I'd better shut that thing off.....................(dull thud in background....)

LOL. My tumbler won't be here for a few days but I already have a supply of lead balls and a 100 foot extension cord. The whole idea is to do this safely

[Freightman]

I just got 10# of KNO3 from Duda Diesel 99% pure and with shipping it came out $3.06 per # I did some figuring and it will do aprox. 20#+ so the cost per # even with buying the sulfur will be at $2+ - not bad for so much fun.

[lavenatti]

Another KNO3 source.

http://www.cropking.com/HydroponicSu...roducts_id=334

[ROGER4314]

Great writeup..........thanks!

I made black powder as a teenager and had a few mishaps and scars to show for it. I'm not sure that I'd do that inside of the house!

The Saltpeter is Potassium Nitrate and one of the major sources of the KNO3 is bat poop. It gets many feet thick in places where large populations of bats "Hang out" (pun intended)! There were battles in our US Civil War where the objectives of the fight were to gain possession of caves that were loaded with Bat Poop.

A few words may be worthwhile here. Black powder WILL explode when crushed and it is generally sensitive to impact. The cap guns we had as kids used BP. Also remember how the caps rusted our cap guns?

Black powder is regulated as an explosive and there are strict regulations on selling and storage. The same restrictions are not applied to smokeless powder or to BP substitutes like Triple 7 or Pyrodex. That's why it's more common to find the substitutes instead of real BP at retail.

Flash

[o6Patient]

markinalpine : GRAPHITE is used to coat the powder it slightly slows the burning process and helps keep powder from absorbing moisture from the air. While Graphite is nearly pure carbon so are diamonds neither burn well because of the way the atoms are chained together.

atom73: Have you ever tried with much less water potassium nitrate will not dissolve in alcohol but every drop of water leaving takes some with it.

Graphite's purpose as applied to powder is to keep it from building up a static charge; it's conductivity.
I don't believe it alone will protect it from moisture per say. In fact graphite, as I understand it...and I could be wrong, gets it's lubricity by capturing moisture from the atmosphere and incorporating into it's structural layers. That is why graphite can cause pitting if left in contact with ferrous metal, under certain conditions, some think it prevents this but in fact it can actually promote corrosion, again I could be wrong, but I did read up on it a little a few years ago and thought I understood it correctly, it was a learning experience for me at the time.

[o6Patient]

markinalpine : GRAPHITE is used to coat the powder it slightly slows the burning process and helps keep powder from absorbing moisture from the air. While Graphite is nearly pure carbon so are diamonds neither burn well because of the way the atoms are chained together.

atom73: Have you ever tried with much less water potassium nitrate will not dissolve in alcohol but every drop of water leaving takes some with it.

Graphite will burn but it's hard to ignite, Diamonds don't burn easily under normal conditions.
(diamonds in a normal atmospheric oxygen level of 20% won't burn until well over 1500 degrees).

Graphite's other main contribution to smokeless powder, which I neglected to mention
above, and is obvious , is that being a lubricant , it keeps separation of the kernels
which is critical to the flow-ability and the powder's particular burn rate.
(again as I understand it)

[hatcreek]

if you ever need belts for your ball mill I use old bike inner tubes cut into bands about 3/8" thick, work great. HC

[OBIII]

I may have missed it, but did anyone come up with the screen sizes for the different grades of powder? Anyone have a source?
I will try this one day, and with the wealth of knowledge in this thread should have an easy time of it. Actually, I made about a pound when I was 13 with just mixing the dry ingredients. Best smoke bomb I have ever made, as I did not think it was ever going out.

OB

[James6406]

Thank for to the OP, the reply posters, and more info links. I found this thread absolutely fascinating. I am 55 and must have spent most of those years in a cave with the bats. I had no idea there were so many people making their own powder. I would love to try this but my wife already thinks I am nuts. Good thing I didn't know about this when I was a kid!

[ofitg]

Sounds like an excellent, well thought out method. I was wondering about the loss of nitrates with the water and, of course, the answer is NOT to wash it away in the first place. I'll give it a try.

Here is an excerpt from Ian Von Maltitz's book, Blackpowder Manufacturing, Testing & Optimizing -

An early Chinese method (circa 600 AD) used a large marble slab to cool a hot mix of Black Powder. They did this by first blending together the sulfur and charcoal in a bowl. A saturated solution of potassium nitrate was then brought to the boil and the sulfur /charcoal mix added to it, with constant stirring.
This hot mix was then rapidly cooled by pouring it onto a cold marble slab, and still stirred while cooling. This stirring aided the cooling process and ensured uniformity in the mix. One method they used to stir the mix was to pass a large stone roller back and forth over the cooling mass of Black Powder.
In some respects this cool marble method is similar to the CIA method in that it works on the principle of rapidly cooling a saturated mix of Black Powder. I don't know of anyone who has tried to emulate this rather unique Chinese method of manufacture. Naturally it comes with the normal dangers associated with a hot mix of Black Powder. It also suffers from some of the deficiencies found in the CIA method, the most important of these being the need to mill the sulfur and charcoal and thoroughly blend these before mixing with the potassium nitrate.
However, it does have an advantage over the CIA method in that there is less chance of losing potassium nitrate through leaching out.

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I might add that it helps not to use too much water! At boiling temperature, one ounce of water is more than enough to dissolve two ounces of KNO3

[mold maker]

That is interesting. I have everything required, and the stone is outdoors, in below freezing night time temps. Looks worth a try.

[ofitg]

I have done something similar.... I mixed the ball-milled sulfur/charcoal with water and then heated it.... when it started boiling, I stirred in the KNO3 (powder) for about 30 seconds and then dumped the "soup" into a large Pyrex baking dish (at room temperature). Within one second or so, the soup cools and congeals into a "sludge" consistency. With a little help from a small desk fan, it dries overnight.

[psychicrhino]

Great read. Very interesting.