Does compaction of BP helps?

[SKC]

My last batch of BP was made by sieveing KNO3,C & S through 200mesh screen. I didn't ball mill anything. I wetted with water, compacted by palm & granulated through a 4mesh screen. I didn't add dextrine even in the fear of loosing BP power.It was crispy when fully dried.

I've successfully lifted 14 shells on diwali with this.

My query is, does compaction helps improve BP power? Actually before granulating I intend to put some mix in a hollow dowell then ram compact to obtain tighter granules.

'Ball mill is essential to advance in pyro, some compositions needs milling' I've read all these. But the problem is still I'm unable to find one or don't know the Indian sources. My Indian pyro friends may extend help.

Till then depending upon limited available resources. I'm ready to put the extra labour if it improves a little even.

Thanks in advance.

[SKC]

And what mesh size may be considered as airfloat?

[Arthur]

You answer your own question! You've lifted shells with this powder so it works! The usual methods of making black powder are well documented on the web on this forum and lots of other places. the final powder becomes better if milled together for some time, but other methods also work. Perhaps using proper milled powder pressed into pucks and corned into granules will make you faster powder meaning that you may be able to use less.

[kingkama]

Puking and corning (pressing and breaking apart) would produce a powder that do not lose her power during the time, constant performance and superior quality.

You can start milling your BP then think about puking and corning. A ball mill is not too hard to make, a old whasing machine or a pump motor two rod of steel 4 ball bearings and a box of wood, 2 pulley of the right dimension, on this forum you will find a tool for pulley and milling media calculation, try before buying an expensive rock tumbler that you must modify anyway. In my opinion what is on market (USA or UE) is not valuable as what you can build yourself, the must hard topic is find the best container for charging media and green mix, that fit your needs.

Edited November 4, 2019 by kingkama

[MadMat]

I built my own ball mill from pieces of construction wood, some 4" PVC pipe (and end caps), a surplus DC electric motor and some furniture casters. I power the motor with an automotive battery charger. Sure it doesn't look impressive and it's capacity is only about 150 grams, but it has effectively made dozens of batches of BP. I made the entire ball mill for less than 20 USD (minus the battery charger)

Edited November 5, 2019 by MadMat

[Boophoenix]

Skc, pucked and corned BP on average will be a little less powerful than screen granulated BP. The screen granulated is more porous and will likely burn faster. Pucked BP is dense ideally at 1.7 grams per cc.

It’s a pretty fair trade off as you’ll get better consistency from pucked and corned powders especially as a beginner by eliminating some of the variables we have as beginners like over wetting and drying. Also no binder is required for solid grains. Some binders can start to weaken the performance of BP as the ratios get higher with the binder.

[Mumbles]

I've also wondered about advantages where space is at more of a premium. IE, does a cylinder shell with the same sized cannule break harder/bigger with pressed powder or with screen granulated powder? On the pressed powder side, it is denser and thus the same size cannule holds more powder. I used to know the conversion, but it's escaping me. It's something like 10-20% IIRC. On the other hand, screen granulated powder is, as you stated, more porous meaning it may burn faster. Just something I've always wondered about.

[SKC]

Thanks to all for useful advices. Let me get a very steady hand with what I'm doing right now and understand BP charecter. Later I might experiment with all the milling & pucking business.

[BetICouldMake1]

I've also wondered about advantages where space is at more of a premium. IE, does a cylinder shell with the same sized cannule break harder/bigger with pressed powder or with screen granulated powder? On the pressed powder side, it is denser and thus the same size cannule holds more powder. I used to know the conversion, but it's escaping me. It's something like 10-20% IIRC. On the other hand, screen granulated powder is, as you stated, more porous meaning it may burn faster. Just something I've always wondered about.

 

I've wondered about this as well. It would seem that for a break charge a faster burn would be more important that fitting more, slower burning, powder. I can see a noticeable difference in breaks if I use -12+20 vs -8+12, which would seem to be the same principle.