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A couple newbie ball shell questions...


braddsn

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Hello guys! I have not actually started building anything yet, or even making bp. I plan to start making my first batch of bp in the next couple weeks or so. But for now, I am just reading and taking in all the info I can about safety, bp, shell construction, etc. I have 2 questions that hopefully someone can answer. Both have to do with the construction of ball shells. First, I have watched several videos about ball shell construction. Some guys use a booster (flash or whistle mix) mixed in with the break charge. What are your thoughts on this? I am asking because I am gathering that making whistle or flash can be tricky/dangerous? And my second question... about making stars. Is there a good reference chart somewhere that gives recipes for all the different types/colors of stars? I have studied the veline chart, and for basic colors, I assume it is pretty solid? I have not been able to find a good chart that gives recipes for all of the other kinds of stars, i.e. tiger tail, strobe, go-getters, etc. I am obviously just delving into this hobby, and most of the information that I have searched for, I have been able to find. But a good "star recipe chart" has been a challenge. And... what is the consensus on booster in the break charge? Thanks!! I am headed to the bookstore next week to buy some pyro literature! :)

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I would not worry about a booster for your first shells. Once you get a working shell, you can decide if you want a harder break at that time.

 

I do not believe a star chart, like you have described, exists. I have found sites that contain many different formulas but not in chart form. Danny Creagan's site has a large number of star formulas.

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Boosting is going to depend on the strength of your burst, and size of your shell. I prefer not to do it personally, but it's also fairly common. Start with out it, get your BP and burst dialed in, and you can go from there.

 

There are a lot of sources of star formulas. Places like www.passfire.com and presumably fireworking.com have nice formulary databases (both pay sites though). There are a few places that get closer though. I included two of the most famous/common ones. Sadly the original sources for both websites are gone, but these are mirrors.

 

PFP database - http://www.privatedata.com/byb/pyro/pfp/Index.html

 

Wouter Visser's Practical Pyrotechnics - http://torontogoat.files.wordpress.com/2012/05/practical-pyrotechnics-by-wouter-visser.pdf (the whole website is archived in that pdf)

 

You may have a little trouble finding actual pyro literature at a book store. Generally its mail order or online now. Still sort of a niche hobby.

 

Another thing you may want to consider is joining a club. http://pgi.org/links/clubs.php You may want to think about Heartland Pyrotechnics Association, MoPyro, Bluegrass Pyrotechnics Guild, or maybe the one in Tennessee depending where in Southern IL you're from.

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I am getting a 404 page not found for the PFP database.

 

That is the first time I have seen Wouter Visser's site, thanks!

 

Braddsn, I didn't realize you were in southern IL. MoPyro is a great club. We don't have many builders but you can learn a lot from the ones we have. You should also consider going to Pyromania in September. It is a big shoot hosted by MoPyro.

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I am getting a 404 page not found for the PFP database.

 

...

 

 

Oops, I had an extra space in the link. Should be all fixed now.

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Thanks for the great info guys! I will take your advice, and hold off on the booster until I get my lift/break bp dialed in. Do most folks roll their stars or cut them? I am still in the research stage, and trying to decide how to do things. I like the idea of rolling, seems like the best way to do it. I have the plans for a star roller, and I am mechanically inclined, so building it would be a snap. Seems like spherical stars would be a little more "usable", and would maybe burn more consistently. Thanks again! :)

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People use what ever tech they need to get stars that do what they want.

Rolled stars are pretty much a must if your doing colorchangers, and most if not all compositions can be rolled, and give you rock hard stars with minimum amounts of fluids.

Cut stars give you stars that can be very precise, to let you fill cylinder-shells in a way that makes you get the absolute most out of them. I've seen people stack stars so tight and neatly that they can take the shell after putting only 1 layer of stars in it, and lay it on it's side, without the stars moving anywhere.

Pumped stars can give you very consistent stars. Especially if you use a starplate, press, and a scale to control how much composition goes in to making every batch of stars.

 

Personally i only use starpumps for "specialty" stars and comets, and everything else is rolled. The downside to this is, finding a barrel that gives consistent size, and round stars have been somewhat of a challenge. Buying a commercial pill coating machine isn't really in my reach, but the shape of the bowl is sort of easy to see from those. Failing to get a bowl that performs perfectly on it's own means that you have to bother with (manual) sorting of the stars. I'm always looking for that perfect bowl, but so far haven't found it. Mostly due to the shape, a bowl that has a small mouth, with a near perfect 180degree curve, and then a flat bottom, isn't very easy to make in stamped metals, so mass-production seams unlikely. I'm sure there is one out there, i just have to find it. And i'm almost positive thats the "perfect" shape. The larger it is, the larger stars it should make while keeping the size & shape consistent.

B!

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Tires, especially a narrow width, high profile type would have the right shape, so i suspect it would do fairly well, but i haven't tested one. Main "flaw" as i see it, is that it cant tilt significantly, and for the stars to rotate in and out of the main growing zone, the wheel would have to tilt to the side, something like 45 degrees.

B!

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www.thegreenman.me.uk/pfp/db1.html

 

click on stars and here are a lot of charts...

 

Everything you need to get started. as a beginner I would stay far away from whistle mix. In my opinion its more dangerous than standard flash powders. Ive taken apart a commercial 3 inch shell on a show, and it was backed with hull coated flash powder. If you make a real nice b.p....then a booster is not necessary. You also might want to try hand rolling. I rather enjoy it...but I tend to do 100-150 gram batches at a time. I recommend getting some willow charcoal for your b.p. Mill it for three hours with out dextrin, rice it..dry it and remill for another three hours, and then rice your finished powder. This will make an excellent lift/ and break charge.

Good luck and remember safety, and incompatibilities,

Best wishes,

Ben

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Thanks Bcorso85, as for the lift charge, do you also use bp coated hulls? Or just straight bp?? I also noticed on some bp charts, there are lift-specific charts. Should I use these lift specific formulas, or just use the standard 75/15/10 bp for everything?

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Just use the standard 75-15-10 bp. It is the right stuff. Also you just need to rice once, make sure your powder is as fast as your mill allows it to becomme (best if it allready stars to stick to the walls).

Depending on your equipment, also have a look into the corning process, it gives a much nicer powder then ricing. If you are just starting and only working with small ammounts a 1" star pump is good to get a first start into this. Later aou will need a bigger one of 2" or more. For this process you need an press.

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  • 1 month later...

http://www.skylighter.com/fireworks/how-to-make/colored-screen-sliced-rubber-stars.asp

 

here is a chart of compatible perchlorate/parlon stars by ned gorski.

 

i personally don't use the blue. it looks ok but burns too slowly to work with the mgal fueled stars.

 

while not in chart form, Niladmirari has uploaded a set of compatible base colors based on a.p. and hexamine that can be mixed in different proportions to get all the intermediate colors. not sure if they are his formulations but i give him credit when i use them. his use of shellac can be subbed by red gum. they are in his gallery.

Edited by rogeryermaw
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Im in the same kind of position of the person who started this thread, starting into pyro. I have a few basic bp chems, a ball mill with lead media, 3/8" and 1/2" star pumps, and some other misc supplies. I'm thinking of starting with plastic ball shells, moving to plastic canisters, and then too Italian paper canisters. I have a lot of kno3 but it is prilled and has a little less than %1 foreign matter (clay, cement, etc..). I have a ton of it and i don't want to trash it, do you think it will still work in tiger tail stars if i mill it into powder?

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you can always recrystallize. and make sure your foreign matter includes no metals.

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I've used prilled KNO3 (champion brand) with a small amount of foreign material for most of my pyro career. It works fine, even without recrystallizing. I had a small amount of recrystallized stuff for certain things, but very rarely used it. The prilled stuff worked fine in essentially everything once ground or milled.

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Thanks Mumbles! Also could i use a coffee grinder to mill it? I don't want to contaminate it with lead from mill media.

Edited by AldoSPyro
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Coffee grinders are so difficult to clean. I would just mill it with ceramic media. Pyrocreations has media for cheap :) Edited by mercyfulfate
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For efficiency I always pre-ground it in a coffee grinder or blender to -20 mesh or so. From there I would usually throw the BP portion of the composition in the mill for 20-30min to grind everything up. I rarely used it as is. I'm not as sold on blade milling as some others seem to be. When I did, I screened it through a 60 mesh screen. It would take a considerable amount of time to generate enough product this way. Even this would generate some fall out. I've done -100 mesh too, but that takes absolutely forever to generate any appreciable amount of product.

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