Black Powder Not Burning Properly

[Tandoori67]

If my black powder burns very slowly and needs more heat to ignite and only leaves behind glowing chunks, what could be the problem?

 

Charcoal-Derwent charcoal for art (ground with ball mill)

 

Sulphur-Sulphur prills for hydroponics (ground with ball mill, still has large chunks

 

KNO3- homemade,grinded finely with ball mill

 

Note-taking i simply mixed the ingredients togeher without using ball mill or CIA method, will it still work?

[SeaMonkey]

Unless all of the ingredients are reduced to very fine powder consistency

and mixed together very intimately, the powder will not work well.

 

Most Garden Grade Sulfur is approximately 90% pure.

 

Derwent Charcoal for Art has substantial Graphite content. Graphite powder

is a very poor performer for any Black Powder mix.

 

How was your Potassium Nitrate home-made? Is it free of contamination?

 

It is easy to make your own Charcoal from suitable wood which will work

exceedingly well in Black Powder.

 

Your Sulfur must be a very fine powder.

 

There are still a few videos on YouTube which show how to make a good

Black Powder. The Wet Process for making Black Powder does work quite

well if the water content while incorporating at boiling water temperature

is as little as possible. It does require careful attention to detail and unless

you've had some experience it can be a great challenge. If trying the wet

process work in very small quantities until the technique is safely mastered.

[MadMat]

Whenever there is a problem with bad burning BP 95% of the time it is the charcoal! Unless the potassium nitrate and sulfur are horribly impure, they are not usually the problem. I agree with SeaMonkey about art charcoal. Additionally, don't bother trying charcoal for aquarium filters or any other activated charcoal for that matter. Now as far as that actual technique of making BP. I know there are other methods that people have made claims about working good, but there are always drawbacks they never mention. So the answer? Ball mill, ball mill, ball mill.... It is the only practical way you are going to get decent, consistent BP IMO

[MinamotoKobayashi]

Hello Chappali.

I'm testing juniper charcoal and it is damn fast!

You can found it here:

 

https://www.rakuten.de/suchen/Werth-Metall?type=merchant&merchant=werth-metall

 

Unluckly it is very expensive, but necessary if You want a BP like a flash!

 

Also, You can follow an old tutorial of mine to obtain a fast BP indoor and safely:

 

https://www.amateurpyro.com/forums/topic/13068-how-to-make-very-fast-kp/

 

Please remind that for "safely" I mean "until the dust is wet".

Edited July 31, 2020 by MinamotoKobayashi

[Arthur]

It's NOT black power til it's properly incorporated (usually in a ball mill). Use a blade mill for the individual ingredients first, then mix and fully incorporate the ingredients for some hours in a mill.

[Tandoori67]

Hi guys thanks for the suggestions. I will be making around 50g batch next with improvements

 

1) Charcoal - Unbranded Willow charcoal sticks from art store (Grounded with coffee grinder)

 

2) Sulphur- Sulphur Prills (Grounded with electric grinder) (This is the only option i have)

 

3) Potassium Nitrate - Obtained from the selective re- crystallization of Calcium Nitrate and Potassium Chloride Solution (bought from hydroponics shop)

 

4) Ball Mill - National Geographic Rock Tumbler with steel balls as media (I also have lead media)

 

Process

 

1) Fuel components are mixed in ball mill and grounded for 8 hours. Ball mill is filled with 1/4 of fuel mixture and 1/4 of milling media

 

2) Black powder is made using CIA method.

 

3) Details will be posted here later

 

Any improvements or suggestions?

 

Previously i used activated charcoal. the black powder did not burn properly and produced smelly sulfur dioxide gas.

Edited August 19, 2020 by chappali

[Tandoori67]

@SeaMonkey

Sorry for the late reply, i lost acess to my account for a while.

1) Noted on the Derwent Charcoal - Can i just buy BBQ charcoal from stores like Home Depot/Walmart

2) Sulfur still has some large chunks, its not really fine

3) KNO3 - Made from Crystalized Potassium Chloride and Calcium Nitrate (I don't have the equipment to test the purity)

[Zumber]

Major problem seems to be in chemicals purity,even unmilled black powder burns easily.

Sulphur never cakes rock hard though it forms lumps but it can  easily be powdered with screen or by milling.

You seriously need high purity commercial fireworks grade potassium nitrate for producing good black powder.

[Tandoori67]

Noted with thanks.

Is potasium nitrate formed through recrystalisation pure?

[Zumber]

If its not working its not that much pure.

Try with different fireworks grade KNO3 to compare its purity.

Is there any residue?

[Mumbles]

I doubt it's particularly pure with a single crystallization.  You'd probably need at least a second crystallization to clean it up.  The by-products of that reaction are all fairly hygroscopic and probably would absorb water over time and slow down BP.