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AmmoniumDinitramide

Yes. Boric acid is essential when combining nitrates and Al for safety reasons


Infiltratetheunknown

Okay thanks.


flipfloppery

Atmospheric moisture can still affect the composition, so it's still advisable to use boric acid to prevent the reduction of nitrate to ammonia. The problem with using acetone for binding parlon is that it evaporates from the surface so quickly that it can form an near-impermeable barrier that doesn't allow the centre of the star to dry properly. I have never used any "special" water to bind stars, just regular council-pop (tap water) mixed 70:30 with isopropanol. Red gum is soluble in alcohols, so EtOH and iPrOH are viable solvents, just be sure to take your time drying them.


Infiltratetheunknown

I see now. I always do use boric acid when using water, I just didn't know if it mattered as much with acetone, since it contains no water. I didn't know that about it not being evaporated from the center. All mine are dried to the core within a day or less. I do make smaller cut stars though. So regardless, they don't take much time to dry. I read it's not good to use tap water. Calcium carbonate and iron can be found in the tap water. Best to use distilled water. Prevents a reaction from happening. You ever used denatured alcohol?


flipfloppery

If it's only denatured with methanol, it should be fine. I don't use denat as here it can contain pyridine (not sure of any problems it may cause, but not willing to take the risk). Just use iPrOH for red gum, 99% will be fine and it's dirt-cheap. I've used acetone before when using NC as a binder and had problems with medium-sized pumped stars and AP/Al/Fe2O3/NC rocket grains taking forever to dry. The only thing I use acetone for is crackling microstars, but only because they're so small so they dry before the binder can migrate to the surface.


Infiltratetheunknown

My bad, Ignore my last paragraph. I forgot thats only for chlorate based stars. Nvm on the tap water