Brilliant Color rubber stars w/o Perch

[XMax]

 

Im going to try them maybe this evening inside a 2.5" shell. Depends what the weather is. But I will surely post a video when tested in the air.

 

Perfect! Looking forward to see the result.

[Sulphurstan]

Redbull, have you made à vid of these stars in the air? All hobby pyros have to experiment with nitrate based color stars... Im currently working on blue with magnesium, cuco3... Still nothing acceptable...

[redbullzuiper]

Redbull, have you made à vid of these stars in the air? All hobby pyros have to experiment with nitrate based color stars... Im currently working on blue with magnesium, cuco3... Still nothing acceptable...

 

I dont have experimented much more with it, as I moved to another hobby space, with more space. I was bizzy making fireworks for my birthday and getting new tools. Currently bizzy with making fireworks for new year.

 

I have one video. But the quality isn't really well https://www.youtube.com/watch?v=MurwXPUJBZ8. Don't mind the break. It was just a really fast made shell to see how they perform. Their color is Magenta when you see it with ur own eyes.

 

I will join you on your experimentations for the blue one next year. As I think blue might be possible using KNO3, CuO, Parlon and PVB and phenolic. But Im not sure. PVB burns very hot, so you can probaly leave the Ai or Mg as this makes the flame too hot for blue.

If you have PVB, try to use it.

Edited December 22, 2017 by redbullzuiper

[calebkessinger]

I'll see if I can snag some formulas for no perc colors.. It'll be a while but I'll ask a friend the next time I see him.

[Sulphurstan]

Caleb, that's nice, thanks in advance!

[CountZero]

Old thread, but would you consider these rubber stars easy enough for a newbie to start with?

 

 

Not totally inexperienced, but have not done much pyro for the last 20 years or so and back then I was mostly about big bangs.

Edited January 24, 2021 by CountZero

[SharkWhisperer]

Old thread, but would you consider these rubber stars easy enough for a newbie to start with?

 

 

Not totally inexperienced, but have not done much pyro for the last 20 years or so and back then I was mostly about big bangs.

Absolutely. Pretty simple. Hardest part might be waiting for them to dry!

 

But you're also going to need to learn to make some decent BP if you want to do anything with your stars besides burn them in a pile or turn them into fountains... Store-bought BP gets expensive fast if you opt for that route.

[Carbon796]

I'm sure it's somewhere else too, but it was faster to just reattach than track it down. All you need to do is change the Shell ID and number of inserts, and it should do the rest. I included some reference information such as common shell ID's, and an approximation of the cannule or cavity in the center of the shell. It will also calculate insert sized based on concentric rings. The math was easy, so I included it.

 

There is a mathematical formula, but since I wrote this little calculator I got rusty and it'd take me a while to remember how it works well enough to explain. There's an article in a PGI bulletin about it, which is where I got the information from initially.

Look up skylighters articles/archives section, on screen sliced/cut parlon stars for some pointers.

Edited January 24, 2021 by Carbon796

[justvisiting]

CountZero, I made these as a newbie lots of times. I use Ziploc brand freezer bags to roll the patty out in. I poke air holes to let the air out, and cut the patty with a sharp knife. I've written quite a bit about how I do it, but I'm not a good searcher for old threads. I strongly disagree with the position that exotic solvent blends are required to achieve proper working times. The Ziploc bag solves the problem of evaporation.

[SharkWhisperer]

CountZero, I made these as a newbie lots of times. I use Ziploc brand freezer bags to roll the patty out in. I poke air holes to let the air out, and cut the patty with a sharp knife. I've written quite a bit about how I do it, but I'm not a good searcher for old threads. I strongly disagree with the position that exotic solvent blends are required to achieve proper working times. The Ziploc bag solves the problem of evaporation.

Some complain of "stringiness" when using pure acetone, that's reduced by introducing 20-25% (or so) alcohols. Parlons differ greatly according to source (and absolute molecular composition), but not that much in my experience.

 

Rubber stars are about the simplest comps, with near-immediate feedback due to rapid solvent evaporation, to learn with. Even with priming, you can shoot them the same afternoon...

 

Ziplocs? Whaaa? No need to bag it--mix it in a dixie cup and roll it with a kitchen rolling pin, cut with a drywall blade, and spritzed with acetone occasionally if your comp dried out too quickly to accept a good priming...

 

Easy stuff!!!

[CountZero]

Thanks for the replies. So these stars go to the top of the list.

 

I plan on making rockets, and while the rocket launch in itself is exciting(well to me at least) it just doesn't seem complete without some form of header. So I have sarted preparing a list of things I want to make so I can order some supplies.

 

I have started collecting everything I need for building a ball mill, just waiting for spring to be able to work on it. While we still can buy BP here it is pretty expensive.

[justvisiting]

This is how they look when I cut them. The picture is small but clicking makes it bigger. There is no need to rush. Stringiness is non-existent if the patties are left to stiffen up and a sharp knife is used. I like this method for the hobbyist-sized batches I make.

Edited January 26, 2021 by justvisiting

[SharkWhisperer]

 

This is how they look when I cut them. The picture is small but clicking makes it bigger. There is no need to rush. Stringiness is non-existent if the patties are left to stiffen up and a sharp knife is used. I like this method for the hobbyist-sized batches I make.

 

Nice n uniform those are. A cinch to screen-cut, too, though I get better uniformity if hand cut. Yeah, never considered the "stringiness" issue to be a problem--once the dough ball is solid enough to work in my gloved hands without sticking, there's pretty much no stringiness to worry about--just gotta work quick (or have a spray bottle of solvent nearby). I use whatever size square dowel side guides atop a sheet of wax paper that's liberally dusted with my first prime. Roll it out and pat a bunch of liberally applied prime to the top side (a spritz or two of acetone if starting to dry out), and cut away. Once mostly hardened and separated and not sticking to one another, they all get a spritz and tossed around in another dose of first prime--they're pretty well covered on two sides (or more if I toss another handful of prime on 'em just after cutting...) and bounce them around a little.. Can do the outer prime at the same time after a brief drying session, or go have a cheeseburger and do it a little later. Or add another outer effect if desired. Simple and forgiving--just gotta commit once you're in action before things dry out (or: use JV's plastic bag approach for mixing--I don't because cant see inside so well, or keep a spray bottle of acetone or acetone/alcohol mix nearby, which is what I generally do). Acetone will dissolve several plastics so be sure your spray bottle can tolerate it so you don't quickly develop a permanent clog...

[Guest]

Maybe a tad off topic but figured I'd ask here while people are talking about these stars.

 

Is it possible to bind these using alcohol due to their red gum content? Maybe even substitute red gum with phenolic resin? I hear phenolic resin can replace redgum in equal parts and that it is a better binder than red gum but Iv never tried it before.

 

Iv made these stars before and liked them but did not care too much for working with acetone. I already have alot of denatured alcohol laying around and it would be nice to reduce the amount of solvents I have to buy.

[SharkWhisperer]

Maybe a tad off topic but figured I'd ask here while people are talking about these stars.

 

Is it possible to bind these using alcohol due to their red gum content? Maybe even substitute red gum with phenolic resin? I hear phenolic resin can replace redgum in equal parts and that it is a better binder than red gum but Iv never tried it before.

 

Iv made these stars before and liked them but did not care too much for working with acetone. I already have alot of denatured alcohol laying around and it would be nice to reduce the amount of solvents I have to buy.

You could try it out on an inexpensive 100g test batch and find out within a few hours how they work. Im sure if the Chicoms use phenolic (PR) for many comps because it's cheap in bulk. I made dragon eggs (DEs) with PR/acetone instead of NC/acetone and won't be doing that again. But I used acetone instead of alcohol as solvent,and my PR didn't easily go into solution so it was more of a slurry. Yes acetone can be toxic if you huff the stuff out of a plastic bag or seal yourself in a tiny room making comps, but if it were really all that toxic,women would be dropping like flies every time they painted their toenails/fingernails (acetone solvent) or removed nail polish (main ingredient,sometimes only one). I like the smell of acetone, actually, and it dries super fast--much faster than alcohol. And if it dries too fast for your liking, you can mix in some methyl ethyl ketone (MEK), also for sale at HD/Lowes, to slow evaporation a bit. By the way, check the MSDS for your specific denatured alcohol. They vary widely in denaturants added. The best is mostly pure ethanol with a little toxic methanol and maybe some color added. But i've seen chem listings of crap I'm not familiar with and only 60-70% ethanol total, that I'd be extra PPE-conscious using. Others have suggested buying E85 fuel at the gas station for super cheap, but I'd want to know what that other 15% was before messing with it. Prefer not working with proven carcinogens like benzene when it's easily avoided and unnecessary. My go-to solvents are 91% IPA for granulating rocket BP, 70% IPA for granulating dextrin-bound BP (with a good long incubation time for dextrin to be activated by the 30% water), acetone for all red gum/parlon/DE formulations, generic paint thinner for silicone comps, and water for most everything else. Many people get away with water for nearly everything (not rubber stars, obviously), but I like my stuff to dry quickly. I would switch to PR/alcohol instead of red gum (RG)/acetone if: 1) it worked well, and 2) it was cheaper. Toxicity of solvent wouldn't really be a consideration (for me). But there are hundreds of different PRs and you rarely know which (or their differences and how they behave in pyro), and there are many types of Parlons (I buy in bulk, so don't worry about performance changes from batch-to-batch) and RG is a complicated mixture of tree sap that can be expected to vary from batch-to-batch. This, too, I stock up in large quantities, because i make a lot of rubber stars. Importantly, RG and PR have different oxygenation requirements and different fuel values, and it might be a mistake to sub them 1:1. For a decent discussion of this, perhaps visit another thread here:https://www.amateurpyro.com/forums/topic/13641-dextrin-red-gum-and-phenolic-resin-replacement-and-recalculation/ . Here's another thread indicating that with metallic rubber stars, PR should work ok. https://www.amateurpyro.com/forums/topic/13688-how-does-phenolic-resin-burn-when-no-perchlorate-is-around/?hl=%2Bphenolic+%2Bresin . There's more info out there, lots, but you'll need to look yourself for anything beyond these tidbits.

 

In short, it'll probably work just fine, but you might need to adjust ratios to account for different fuel values. If you try it, please report back. I don't use phenolic for too much, but if it works well, then I'll have a back-up when my fat bag of RG gets depleted. By the pound, PR is now cheaper than RG from common firework vendors, unless you buy in bulk. And whether real or imaginary, some vendors have had difficulty restocking RG lately, so I bought up a bunch (I like the stuff). Besides Parlon, I try to avoid burning plastics/rubbers when it's convenient--we already create a bit of pollution in an already over-polluted world; it's unavoidable, but can be minimized within reason...

[justvisiting]

I don't have a lot of experience with phenolic resin, but the experience I have seems to indicate that's it's not very good for cut stars. It's true that the stars will dry as hard as rocks, yes. But cutting them is a nightmare! At least, it was for me. It was like trying to cut cake into little cubes. When I used phenolic resin to roll stars, they stayed soft for several weeks. When I dissolved phenolic resin in isopropyl alcohol and evaporated the solution on parchment paper, I was left with a soft pancake of resin that stayed soft for almost a year! This stuff does not seem to like to give up the alcohol very easily.

 

I think where phenolic resin really shines is with pumped stars, where the alcohol percentage is just enough to activate it as a binder, but not enough to allow it to form a skin.

[robbo]

Shellac behaves the same way. Too much alcohol in a shellac formula is difficult deal with. The trick is to be patient (another concept with which I am familiar, but have little experience) and allow the binder to get gradually sticky.

[redbullzuiper]

I don't have a lot of experience with phenolic resin, but the experience I have seems to indicate that's it's not very good for cut stars. It's true that the stars will dry as hard as rocks, yes. But cutting them is a nightmare! At least, it was for me. It was like trying to cut cake into little cubes. When I used phenolic resin to roll stars, they stayed soft for several weeks. When I dissolved phenolic resin in isopropyl alcohol and evaporated the solution on parchment paper, I was left with a soft pancake of resin that stayed soft for almost a year! This stuff does not seem to like to give up the alcohol very easily.

 

I think where phenolic resin really shines is with pumped stars, where the alcohol percentage is just enough to activate it as a binder, but not enough to allow it to form a skin.

 

Hm, pretty wierd. I almost exclusively use phenlic as binder in almost all formula's. I either replace the red gum with phenolic, or replace the dextrin.

I roll all my stars and they dry within 7 - 12 days. Rolling stars with phenolic resin makes star rolling so much easier.

 

Are you using a drying box perhaps? Drying the stars in a drying box with heat wont make them hard, instead it softens them. The best way I found to dry them is inside a drying box without hot air, just a fan blowing air through it. Maybe that speeds up the evaporation of the alcohol, I dont know for sure, but for me it speeds up the drying time.

[justvisiting]

I will admit to having limited star rolling experience. Perhaps I used too much alcohol when I rolled them. Eventually- after a few weeks- they did harden.