Plasticize the sulfur?

[Richtee]

OK. Soooo.. I’m on a quest with BP.

 

I was watching a video that really taught me nothing, but there was the mention of the sulfur being the binder. Under enough pressure it “plasticizes"

 

Really? Just curious.

 

On edit.. pressing a puck now with NO moisture at all. ‘Bout to bust it out. Hmmm

Edited July 26, 2023 by Richtee

[Richtee]

Fail. Stuck so firm to my piston I had to chip it off. Hard as balls tho.

[Richtee]

No dry time. Fast too. 5 mins Out the press.

[FrankRizzo]

We did a series of tests over on Passfire years ago that measured binding and reactivity with just ball-milled BP and no binder, but with adding various amounts of moisture. Adding between 2-3% of moisture was the sweet spot for granule hardness and density approaching commercial Goex (1.7g/cm).

 

If I let my ball mill run for around 4hrs, I'll also often end up with a nicely consolidated chunk stuck to one end. I've simply granulated that before, and had good luck.

[Richtee]

We did a series of tests over on Passfire years ago that measured binding and reactivity with just ball-milled BP and no binder, but with adding various amounts of moisture. Adding between 2-3% of moisture was the sweet spot for granule hardness and density approaching commercial Goex (1.7g/cm).

 

If I let my ball mill run for around 4hrs, I'll also often end up with a nicely consolidated chunk stuck to one end. I've simply granulated that before, and had good luck.

To quote Arte on “Laugh-in” Veeerry interestink!” I get that at the base of my jar too. I gotta beat it with a stick to empty. I could not get any data from that puck without using a Fourier Transform I figger, but the usual on the symmetrical pucks I get about 1.6 G/CM. I get 1.7 before they dry, tho

Edited July 26, 2023 by Richtee

[Arthur]

At Royal Gunpowder Mills, Waltham Abbey, ingredients were milled/incorporated, then placed between brass shim plates in stacks. The stack of shims and powder was then pressed. The shims could then be flexed to release the powder.

[SharkWhisperer]

I was watching a video that really taught me nothing, but there was the mention of the sulfur being the binder. Under enough pressure it “plasticizes"

 

Really? Just curious.

Sulfur is an odd ducky. Low melting point (240F/115C for our non-American colleagues) and if you melt it and dump it into cold water it turns into a rubber-like plastic amorphic substance.

 

It's thought that sulfur can undergo plastic transformation to some extent during milling BP, for example, which allows it to flow better into/around charcoal pores and around KNO3 particles for increased chem incorporation.

[Richtee]

Thanks Shark. Again... I’m pretty informal in chemistry.