6 replies to this topic

[GreenGenie]

Is there any reason that I shouldn't grind Potassium Nitrate & Sulphur in a pestle & mortar?

The BP I am making is working fine for what I am doing. I keep ready weighed charcoal, sulphur and nitrate in bags which I then mix together when needed.

However, the sulphur despite my best efforts to keep the air out of the bags tends to be a little gritty. I would like to grind it in a pestle and mortar to smooth it out and at the same time I might as well add the nitrate to help combine them and make a better mix. I suppose it would be dangerous to add the charcoal to the pestle and mortar as well. I dont have a ball mill and anyway I feel a little nervous of ball milling gunpowder.

[oli]

Is there any reason that I shouldn't grind Potassium Nitrate & Sulphur in a pestle & mortar?

The BP I am making is working fine for what I am doing. I keep ready weighed charcoal, sulphur and nitrate in bags which I then mix together when needed.

However, the sulphur despite my best efforts to keep the air out of the bags tends to be a little gritty. I would like to grind it in a pestle and mortar to smooth it out and at the same time I might as well add the nitrate to help combine them and make a better mix. I suppose it would be dangerous to add the charcoal to the pestle and mortar as well. I dont have a ball mill and anyway I feel a little nervous of ball milling gunpowder.

Hmmmm to make it safer try to keep the oxider and fuel away from each other. if possible use one mortar and pestle for charcoal and sulpur and the other for the KNO3. Although ball milling in your house can be a scary thought, in can be made almost completly safe by using a non sparking media such as lead and dampening the composition with a spray bottle containing alcohol or water. If you are still not confident you could mill the components separately ( 2 different barrels) or construct some sort of housing devise for the mill outside (remembering noise, waterproofing etc)

Hope this helps

Oli

[seymour]

Hmmmm to make it safer try to keep the oxider and fuel away from each other. if possible use one mortar and pestle for charcoal and sulpur and the other for the KNO3. Although ball milling in your house can be a scary thought, in can be made almost completly safe by using a non sparking media such as lead and dampening the composition with a spray bottle containing alcohol or water. If you are still not confident you could mill the components separately ( 2 different barrels) or construct some sort of housing devise for the mill outside (remembering noise, waterproofing etc)

Hope this helps

Oli

Yes, it is good to keep this in mind.

Is there any reason that I shouldn't grind Potassium Nitrate & Sulphur in a pestle & mortar?

The BP I am making is working fine for what I am doing. I keep ready weighed charcoal, sulphur and nitrate in bags which I then mix together when needed.

However, the sulphur despite my best efforts to keep the air out of the bags tends to be a little gritty. I would like to grind it in a pestle and mortar to smooth it out and at the same time I might as well add the nitrate to help combine them and make a better mix. I suppose it would be dangerous to add the charcoal to the pestle and mortar as well. I dont have a ball mill and anyway I feel a little nervous of ball milling gunpowder.

It'll be safe.

[Richard H]

The word 'relative' should be implied here. It is relatively safe to prepare a small amount of blackpowder type composition in a mortar and pestle, provided there are no abrasive components like Titanium for example. Of course you should be taking sensible precautions like limiting the quantity involved, and wearing appropriate hand, eye, and face protection.

[knackers]

edit :- wetting your Bp comp in a ball mill..... forget it, it will ust be a pain in the bottom, its not needed, if pyrotechnics isn't time consuming enough as it is, without making it harder

Edited by phill 63, 22 April 2009 - 08:21 PM.

[BrightStar]

i hear and respect what you say oli, and you can't ( well actually you can ) be too safe

I agree in part, but amateur or professional pyro is an inherently risky activity. We shouldn't make it more so.

Hand grinding a 20g batch of BP in a pestle and mortar is a useful learning activity and something I'm quite happy doing myself. Having said that I'll mitigate risk by doing it in the garden wearing gloves and goggles.

As for milling BP, the nature of probability is that even given 100 successful batches, batch number 101 might still cause disaster. When accidents happen it's often the case that a number of 'bad luck' factors come together at once. That's not something we can analyse or predict. I assume my mill will blow up one day and treat it accordingly.

Edited by BrightStar, 21 April 2009 - 08:07 AM.

[knackers]

i do understand the inherant danger, and asimilate it to our every day life, " your chance of being hit by a car is probably more realistic than having your Bp mill or mortar and pestle going ballistic, although it is wise to be safe,

Edited by phill 63, 22 April 2009 - 08:22 PM.