Jump to content
APC Forum

which-dextrin,rg,cmc


Recommended Posts

Posted

Oh, dextrin I know. That's the tricky thing. Dextrin is very simple and predictable: just a little bit of water and 25% alcohol in the water. SGRS behaves differently. But I'll try again until it works.

 

It's nothing wrong with my SGRS. I made some extremely hard blue stars with it. Never made stars with so much charcoal before, though, even if TT is "easier" than coloured stars.

Posted

Nice with respons. :rolleyes:

 

I know that it might seem very amateurish, since I have made pretty big shells with parlon stars, but I really have trouble with my SGRS. I have rolled and pumped dextrin stars without difficulty, but SGRS seems to work differently. Some KP stars became rock hard, but these won't. Some zink stars I made last year were also like this.

Posted
SGRS is a tricky thing to pump with. The one bit of advice I can give is to really give it time to activate. Someone I know lets it go overnight. I'd start around 10-12% water, and kneed it in or screen the comp to fully distribute it, then seal it up and give it time to sit. I'd be leaning toward minimally 30 minutes to an hour just to be sure. Once it becomes sufficiently activated, I've found you can adjust it easier with a spray bottle to get to the optimal pressing consistency.
Posted

Oh, I'll try that.

 

The "funny" thing is that pure SGRS gets "jelly-like" within few seconds.

 

Another remarkable thing (a bit off topic but interesting) is how much the water changes the composition's burn rate. In a dry state it hardly burns, but once moist it burns pretty quick, giving off big orange sparks even on the ground.

Posted
Update: despite me having bronchitis I made a 100 g batch and sprayed 12 grams of water on it. It was allowed to soak for 70 minutes. I could pump the stars, but they didn't adhere well, so now I let them soak until tomorrow in a sealed plastic can.
Posted (edited)
Update 2: still problematic. I think this is why Shimizu recommended a wet process, apart from incorporating the KNO3 into the charcoal. They still won't adhere especially well 16 hours after I made a batch and sprayed it. Now I sprayed it with some more water and let it sit overnight in the plastic can. Edited by Potassiumchlorate
  • 2 weeks later...
Posted
Uppdate 3: the SGRS is incredibly strong on its own. I put ½ tablespoon of it in cold water about 24 hours ago. It's still jelly-like in the middle but rockhard in the edges. Maybe I put in too less water after all? But I started with 12% by weight and I think there was about 20% in it when pumping the last stars.
  • 5 weeks later...
Posted
Update 4: I have made a few 10 mm pumped stars with 50AEs bright blue and SGRS instead of dextrin. They seem to be rock hard once they're dry. Charcoal stars didn't work that well for me, though.
  • 1 month later...
Posted

Update 4: I have made a few 10 mm pumped stars with 50AEs bright blue and SGRS instead of dextrin. They seem to be rock hard once they're dry. Charcoal stars didn't work that well for me, though.

 

 

Thanks for keeping us updated on your progress Potassiumchlorate. Did you end up working out a solution to the SGRS and water dilemma?

Posted

Thanks for keeping us updated on your progress Potassiumchlorate. Did you end up working out a solution to the SGRS and water dilemma?

 

I'm not really skilled at it yet, but it seems that it must:

 

1. Soak for a long time and maybe also

 

2. be pushed trough a rather coarse screen to be fully integrated.

×
×
  • Create New...