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bjmac
01-06-2023, 02:50 PM
Hey all. I'm new to this making fireworks thing. I've made bp so far and it seems pretty quick. I'm going to in the next few months be ordering a 1.75" shell kit to start learning. I plan on using the d1 in the kit, granite stars, chrys 6, and possibly the rubber star kit. I'm pretty much going to be following the websites info and "Mr. G's videos. My question is star size and burn time. I'm thinking I should do 1/8" or so stars? If I do they won't last too long in the sky. My question is will I need a stronger break charge than standard bp? My thinking is the faster and further they go the more effect with the short burn time.
Any advice or thoughts would help me out.

PyroJoeNEPA
01-06-2023, 06:59 PM
You can use up to & including 1/4" stars in a 1.75" shell with good results. Naturally, the larger the stars, the less you can fit into a 1.75" hemi.
A good hot black powder [granulated fine--around a FFFA will break your shells quite well. Most Chinese manufactured shells only use BP--not coated rice hulls in the smaller shells.
Rubber stars are very easy to make and offer a lot of color variations by mixing the formula up. Use a good BP prime for them.
For the other stars, look up Monocopa Prime for them. I use it on almost everything.
Good luck & be patient with your mixes...it takes a while to get the hang of it. Dyring time is very important.
Breaking them too hard will cause the stars to "blow blind"--i.e. spread out from the shell before they are ignited.
***What part of PA are you in? We have a couple great clubs here in PA.

bjmac
01-06-2023, 09:12 PM
Wow, I would have never thought i could go to 1/4" stars. I figured they would burn to the ground. Awesome. (Never made stars or obviously tested.) Would the coated rice hulls be better? I ordered them years ago when I went through the "bug".
Can you cut the rubber stars? I don't want to do the other methods just yet.
Thank you for the info. Sorry for the questions. Just trying to get the best info before I dive in.
Most of what I have seen so far calls for all to be bp primed after the hotter prime, still with the monocopa?

bjmac
01-06-2023, 09:21 PM
I'm just outside of Philly and De.

PyroJoeNEPA
01-07-2023, 11:59 AM
Wow, I would have never thought i could go to 1/4" stars. I figured they would burn to the ground. Awesome. (Never made stars or obviously tested.) Would the coated rice hulls be better? I ordered them years ago when I went through the "bug".
Can you cut the rubber stars? I don't want to do the other methods just yet.
Thank you for the info. Sorry for the questions. Just trying to get the best info before I dive in.
Most of what I have seen so far calls for all to be bp primed after the hotter prime, still with the monocopa?

No problem with the 1/4" stars--especially with the rubber ones. I would use BP for the break to get started--it takes less room than the coated rice hulls and lets you get a few more stars in the shell.
I use a pizza cutter wheel for the rubber stars then prime them with the monocopa. No need for the 2 step black prime and hot prime if you use the monocopa.
Even with the 1/4" stars you can make charcoal based [willow] stars and they will burn out before they hit the ground---assuming you use the proper amount of lift & get them to a reasonable height.
Don't apologize for asking questions. That is how we learn & tweak our skills. And that is what we are here for---to help each other!

bjmac
01-09-2023, 09:21 AM
So yesterday I was on YouTube and stumbled across a documentary on fireworks, Howard and sons. He mentions when making stars that adding water to magnesium can make it spontaneously combust while drying. I take it that's why rubber stars use acetone? In other words don't use water with magnesium... same go for magnalium?

PyroJoeNEPA
01-09-2023, 11:05 AM
So yesterday I was on YouTube and stumbled across a documentary on fireworks, Howard and sons. He mentions when making stars that adding water to magnesium can make it spontaneously combust while drying. I take it that's why rubber stars use acetone? In other words don't use water with magnesium... same go for magnalium?

?



When magnesium interacts with water, it will form a hydrogen gas that ignites violently due to the excessive heat and oxygen supply. When it reacts, it will burn hot enough to decrease the water molecule, which turns to a Hydrogen Gas.

Magnesium metal and its alloys are explosive hazards; they are highly flammable in their pure form when molten or in powder or in ribbon form. Burning or molten magnesium metal reacts violently with water.

Engineer Cat
01-10-2023, 01:57 AM
?



When magnesium interacts with water, it will form a hydrogen gas that ignites violently due to the excessive heat and oxygen supply. When it reacts, it will burn hot enough to decrease the water molecule, which turns to a Hydrogen Gas.

Magnesium metal and its alloys are explosive hazards; they are highly flammable in their pure form when molten or in powder or in ribbon form. Burning or molten magnesium metal reacts violently with water.

and this is the reason I don't mess with Alchemy ;)

bjmac
01-16-2023, 11:20 AM
Hey, I'm new to this. Lol. Thanks for the reply. I guess I never gave magnesium too much thought. I'm aware of almost any fine particle metal being a hazard. I've grinded and heated magnesium housing, know it can be welded and have seen it used in wet environments. I always treated it mostly like aluminum. Hey, learn something new every day. Thanks for the info.