Whats wrong with my BP

[ucorky]

I have a small match of BP made up. I used averages of other formulas of:

73g PN
11g Char.
16g Sulf
10g Dextrin

The result, after milling, wetting, drying, crushing, milling, crushing, milling, drying, etc. are clumps that, when taking a small 1 cubic cm., zip around the table when lit. I was attempting to make lifting powder. What on earth have I done? This stuff is half useless. Can I recover? Also, this small chunk zipped around the tabletop in like 3 seconds time and smoked like hell but it burned, yes it did indeed.

I have since then gone in and added more charcoal and PN in hopes I may have 'fixed it'. This stuff is all very very fine by the way.

[Bert]

Leave out the dextrin. Change the ratios to 75:15:10 Potassium nitrate:charcoal:Sulfur

What do you mean by milling. Ball milling? Edge runner mill? Your mom's osterizer?

[Cobalt.45]

No big deal.

Add 47g KNO3, 13g charcoal, leave the sulfur where it is, and you'll be at 75/15/10. Subtract whatever C and KNO3 you've added from these amounts.

The dextrin shouldn't be a problem.

If you've used some up trying it out, etc., divide the remaining weight of the batch by what you started with. Multiply the amounts I gave you by this result, then add.

Potassium nitrate isn't PN, but it can be KNO3. Char is usually C, and Sulf is usually S. Weird abbreviations tend to confuse, or worse.

[Bert]

I'm sure at the stage ucorky is at, there are much more important considerations- but what kind of charcoal are you using? Kingsford briquettes out of your dad's bag in the garage make poor black powder. They're adulterated with limestone, Sodium nitrate, binders and other trash. Besides, every new chemist/pyro should try what I recall as my first lab- The destructive distillation of wood. (Ideally with some nice de-barked willow twigs)

Cobalt, the highest performing black powders contain no additional binders. This is a uniform practice, industry wide and spanning centuries... Binders are now added by some oriental or hobby manufacturers in lieu of consolidation and graining procedures that would yield higher grade propellant powder of similar grain durability, but the binders definitely detract from the performance and are not at all needed if enough pressure can be applied to the milled mix.

[nbk2000]

Oh, and activated carbon/charcoal, as found in the pet supplies section, makes for a very poor BP too.

The charcoal needs some volatiles content in order to function. Too pure, and it's poor fuel.

[Cobalt.45]

Cobalt, the highest performing black powders contain no additional binders.

I'm aware of what BP contains, but thanks for the refresher.:rolleyes:

[Lewis]

My most joyful pyrotechnic experiences have been the production of Black Powder.

Some words of advice: Keep it simple, no need for all the steps.

When I was starting, I powdered all the ingredients together until very fine and homogenous. Then I tested this dry mix of all the ingredients, which if done correctly should burn steadily with a bright orange/yellow/white flame. I then simply mixed very well with water into a paste, waited for the paste to partially dry, and screened it.

Barbecue briquettes will work, but they detract considerably from the performance. I always got my charcoal from my back yard fire pit. Definatley consider investing in a ball mill if you have not already, this will be invaluable to your particle size.

Good luck and don't blow up any cannons. ;)

[Cobalt.45]

ucorky, you may want to check this site:http://www.unitednuclear.com/bp.htm, if what you're trying to do is:

Black Powder that is granulated and used for launching shells and salutes is called "Lifting Powder".
The procedure for making lifting powder is easy, but it sometimes takes a few tries to get it perfect.
Basically all we're going to do is to add a little of a water soluble glue ( Dextrin ) to the Meal Powder, mix it well, get it a little damp, and push it through the spaghetti strainer again. This will produce small granules of Black Powder perfect for launching shells or anything else.

The idea is, keep the grain size larger than for use in a "sporting" firearm. It'll burn slower, so as to not burst your mortar, hopefully.

UN's site explains it better than I.

[ucorky]

thanks. btw, not a kid here. I guess you guys get a lot of minors on here or something. I'm fairly new to this board but not new to the world by a long shot. :) My mill is just a slightly modified rock tumbler unit and some lead balls.

The charcoal I used is from U.N. (quite fine) and I know PN isnt the proper identifier for KNO3. Sort of forgot who I was talking to. You guys are in another league from me for sure, but I am learning.

I guess I used way too much sulfur. I am going to drown out the bad mix by making the adjustment mentioned above. I dont think I'll test it though for a few days.

Now, my flash powder worked great. First try. That stuff is hard to screw up but certainly easy to screw up ones self with.

[30yearstoolate!]

Your original sounds almost like a nice star mix. If loaded into an areal shell with a lift charge and a bursting charge it might make a good chrysanthemum shell.

A good way to make small amounts of charcoal I have came across on this forum is with newspaper. Many have good quality after an attempt or two. And also it is alot cheaper than buying it.

[edit: capatilization]

[ucorky]

good stuff thanks. Newspaper eh? Carbon is carbon I guess.:cool:

[nbk2000]

Using newspaper for making charcoal is very messy, as it disintegrates into an incredibly fine 'airfloat' dust, at the slightest touch.

[festergrump]

Lewis seems to have the right idea... get your charcoal from a fire pit and ballmill accordingly. Willow charcoal is supposedly the best. Has your neighbor got one of those huge weeping willow trees obstructing your view? Doubt he'd miss a branch or two every now and again... Any hardwood will be better than softer woods, rule of thumb.

Newspaper is made from pulpwood which means mostly various types of narrow pine (not hardwood) will be the major percentage of it. While this might work okay, it's not the best, though the airfloat that NBK mentions from newspaper ash would allow not needing a ballmill, at least for the charcoal. Messy, yes, but it'd be a trade off in messiness and quality versus lack of tools. Everything has a price.

I have a ballmill (old rock tumbler) but end up using a mortar and pestle more frequently. Call me old fashioned.

[Sausagemit]

I have a willow tree in my front yard :rolleyes:

Also if there is a place near you that uses and gives away used pallets: lumber yards, grocery stores, department stores, ect. Those are made out of oak that did not make the furniture cut. I found this stuff to make excellent charcoal.

[Bert]

Willow (nearly any species), Black Alder (AKA European Buckthorn), Apple or Peach, Elderberry, these all make good propellant black powder in my experience.

When cooking charcoal, do not over cook it. Some volatiles apparently need to be left in the finished charcoal for best performance. Perhaps use a gallon metal paint can with a SMALL hole in the BOTTOM filled with pieces of willow or other wood about an inch or less in diameter and with the bark removed.

Set the can in a campfire or over a BBQ grill, you'll see a flame at the vent hole as the wood distills. Stop cooking when the gasses leaving the vent hole no longer burn. Remove the can and set it on sand or loose dirt with the vent down (prevents entry of air and your charcoal burning up!).

Leave it alone until it is completely cold. Discard any portions that are not black and crumbly. You're going to want a ball mill, unless you LIKE having black boogers.

[Alexires]

I've found that charcoal (not the bbq) can be purchased in big bags.

Can't find a picture, but when opened simply look like burnt black wood. Works very well in BP compositions. Looks like this. (http://www.historyforkids.org/learn/environment/pictures/charcoal.jpg)

[Bert]

I have bought ground charcoal both as air float and 80 mesh in big bags- It is apparently made from pallet wood. I have learned to screen it before mixing with any oxidizers, as it has occasionaly contained NAILS. Not a contaminant you'd like in a blackpowder mix while milling or pressing!

[Sausagemit]

NAILS

And even if you make your own charcoal out of pallets make shure you screen it for nails as I have had nails slip through during the initial process before I put the wood in the fire and make it all the way to the grinding/milling process undetected.

[Alexires]

....nails.

What the fuck? My stuff looks like it was small logs in a previous life. Then again, better safe than sorry.

[Bert]

It's not a bad idea to screen all your ingredients separately. I have found such things as BUGS in powdered red gum, small rocks and pieces of wood in powdered metals (someone obviously spilled a drum, and just swept it up and packed it for retail sale) and particles, crystals or clumps of chlorinated rubber, oxidizers and fuels WAY out of specified mesh size- Some of these are merely annoying, some are potentially quite dangerous. I will never buy Brazillian "Elephant Brand" BP again after finding trash in it suggestive of it being piled on bare ground and shoveled into sacks at some point in its manufacture.

[c.Tech]

My stuff looks like it was small logs in a previous life.

Are you talking about those perfectly round carbon cylinders you can buy in the super markets and hardware stores? If so how are they?

It looks too pure to me.

[ucorky]

Nah, Are you talking about fuel pellets? Those are like fine wood pressed together I think. The smell always reminds me of IkEA furniture right out of the box.