Flash-core stars

[ZoSo357]

Hey all,

 

I've been planning for new years (yeah, allready!) and I've been looking into star formula's and the like. I came up with this idea of making stars that burn then make a pop (yeah this isn't really origional) but my idea was to use 70/30 perch/Al flash powder, wet it, and pump very small cylinders or roll small stars, then either make stars to insert them in, or roll them with another star mix until enough mixture covers them for them to burn somttime then burst.

 

I was just wondering what the hazards could be. Do you think there could be a problem with wetting perch/Al flash, pumping, then coating in a star mixture (consisting of black powder chems for white/orange depending on ratio's) ?

 

Any tips and idea's are welcome. Let me know your opinion!

[Von Bass`]

I think some people use a small amount of flash in a pill box type star - the same as a normal pill box but with one end closed off.

 

I think it would look ace and really give an unexpected end to a show, but incompatibilites would be a problem - sulphur?

[ZoSo357]

well with chlorate flash it would, perchlorate flash can handle sulfur. It forms perchloric acid instead of sulfuric/sulfurous.

 

Note: Although I think aluminum/potassium nitrate may be a problem (if they become wet, it can heat up, and wetting is mandatory in most cases for making stars) yet boric acid should solve that.

[Frozentech]

Hey all,

 

I've been planning for new years (yeah, allready!) and I've been looking into star formula's and the like. I came up with this idea of making stars that burn then make a pop (yeah this isn't really origional) but my idea was to use 70/30 perch/Al flash powder, wet it, and pump very small cylinders or roll small stars, then either make stars to insert them in, or roll them with another star mix until enough mixture covers them for them to burn somttime then burst.

 

I was just wondering what the hazards could be. Do you think there could be a problem with wetting perch/Al flash, pumping, then coating in a star mixture (consisting of black powder chems for white/orange depending on ratio's) ?

 

Any tips and idea's are welcome. Let me know your opinion!

Flash core stars don't give a pop. What they do is burst into a very bright flash of light at the end. By wetting and pressing, you consolidate the flash powder into a bright white star. Using a dragons egg as a core for a rolled star gives the effect you want, of star burning normally, then popping loudly at the end. You can either make your own dragon eggs, or salvage them from those cheap 1.4g crackle balls, and use them as cores. Somehow the Chinese are rolling perfectly round, well primed eggs.

 

I like to press dragon eggs into stars using a star plate, half filling all the cavities, then dropping and egg or 2 in each one, fill the rest of the way with a star comp, and pressing. Works fine, not as well timed as rolling them I suppose, more of a ragged storm of crackles when the stars burn.

[hst45]

If you have access to reloading supplies primers will work as rolled star cores giving a report. It's not original, but it works. In my experience they have three drawbacks: 1) they are a whore to start to roll 2) they don't work in candles since they reach ignition temperature before leaving the tube and 3) cost. Other than that they have given me good service.

 

The Chinese have a two thousand year head start on me, but I've personally never had good luck with my own dragon egg cores. These would obviously be MUCH less expensive, but I estimate that only about 25% of my cores pop, even on a good day. It sucks to be me. Good luck and keep us informed of your work.

[shadopyro]

I found a tool set on wolters tool site which'll make this possible!

The star pump is one which makes hollow stars with a cavity down the middle. a bit simillar to the crosset stars but the cavity is uniform. Then the stars can be filled with flash or just another colour.

[Mumbles]

Still wont work. Filling with flash will best case scenario make a crossette, worst case scenario completely demolish the star.

 

There is a color to report tutorial on passfire that does work though. Basically you press a color comp into a tube, and fill with appropriate amount of flash and close it off. I believe passfire uses a clay bulkhead between the color and report. If you have good flash you shouldn't need it though. A piece of use is used as a passfire between the color and report on passfire.

[cplmac]

I don't think wetting it will have an adverse affect unless you have magnesium in the mix, but I would never press flash, wet or dry.

[shadopyro]

Damn, worth suggestion. So what if the flash was encloed into a flash bag and then into the cavity, therefore the flash going off after star has finished burning?

 

"I don't think wetting it will have an adverse affect unless you have magnesium in the mix, but I would never press flash, wet or dry."

 

-I dont think the flash is actually wetted though, i htink the star comp is pressed dry, the clay "nozzel" is pressed in place leaving a cavity left for the flash powder. then the flash is simply added into the cavity and sealed with a plug- am i right mumbles?

[Mumbles]

That is correct, and the star comp is pressed wet by the way. I've only used red gum bound stars, so they're alcohol bound. It is a bit more rubbery and is easier pressed and consolidated in.

 

I never thought about the flash reacting with the wet comp. Make sense to use the clay now though.

 

 

 

As far as the flash bag, do you really expect the star not to burn through it? Also is it really worth the effort? Just attach a comet to a tube with flash.

[shadopyro]

Meh fair enough, i was sorta thinking of a rather thick bag like coated in sodium silicate or whatever, but its just a waste of effort.

I understand now that the tube with comet is much better.

[brother john]

Picked this up awhile back on creagen.net. Special Effects Star:

 

Click on picture to see the movie

~1/2" Blonde Streamer round star and 3/16" flash core.

Star gun launch with 1/2 gram of Benzolift.

 

Name: Flash Core

Source: David Bleser (as listed on Passfire)

 

Barium Nitrate 66

Aluminum, flake, dark, German Blackhead. 3 micron 27

Dextrin 6

Boric Acid 1

 

Preparation: Must use flash core igniter formula as a prime (see igniter prime below). Roll with 50/50

water/alcohol, not exceeding 3/16'' diameter and dry. Roll at least 1/32'' thick igniter

prime before rolling on next layer of star comp. Star must be moving through the

air to accurately test for proper operation. Click on the above picture to see a short movie of the flash core in action.

 

Never did a copy and paste on a post before. I don't see the picture that is referred to here within my reply so I am pasting it now. http://www.creagan.net/fireworks/flashCore3.wmv I haven't tried this myself but am planning on doing so for New Year's. We'll see. Hope it works for both of us!

[ewest]

If you have access to reloading supplies primers will work as rolled star cores giving a report. It's not original, but it works.

I just read that in Blesers book on Round shells and stars. I was like WTF?!? Use pistol primers as cores for exploding stars?

 

But the more I think about it the more I like it. I guess I need to find out when the next gun show is.

[qwezxc12]

If you have access to reloading supplies primers will work as  rolled star cores giving a report. It's not original, but it works.

I just read that in Blesers book on Round shells and stars. I was like WTF?!? Use pistol primers as cores for exploding stars?

 

But the more I think about it the more I like it. I guess I need to find out when the next gun show is.

I use CCI or Winchester Large Pistol primers inserted into 3/8" pumped stars for faux-dragon's eggs. I usually put them in BP/MGAl as it takes fire absurdly easy and burns very hot so I'm assured the primers will fire.

 

I don't think they're expensive - I just bought a box of 1000 for $23.00 - they are a bit tedious to use in my star plate; fill 1/2 way or so, insert primers, fill and press.

 

Here's a video of a test of the first batch of these stars I ever made in a small 1-1/2" mine with ~35g of white BP/MgAl pistol primer and AFN Orange Ti stars:

Video

 

I also submitted two 2" mines with these stars in the competition forum:

Mine submission

 

As you can see, they don't 'cook-off' in an even rate. Rolling them into consistantly sized stars would help as the primers are located at various depths in the pumped stars - sometimes you can see the primer poking through the side of the cylindrical star.

 

I do like their effect when they're mixed in with other colors / effects. Alone, they're not impressive enough, but they do spice up a mix of stuff.

 

Nasty Pb3O4 Dragon's Eggs sure do look better, though. Sooner or later I'm going to try to make them. I also plan to try fine mesh CuO / Al thermite cores bound with NC laquer.

[ewest]

You know, I saw your mine submissions and didn't even pay attention when you mentioned the pistol primers. It is a pretty nice effect isn't it? I think I'll put it on my list of things to try; stupid list keeps getting longer and longer though.

 

On the dragon eggs note, I've made 3 different batches so far (100gr each) and made them 3 different ways. Each way I tried I was trying for the easiest, and the most efficient way to get a common size but at the end of the day I ended up taking all three batches and grating them through a 40 mesh screen to get some cores about the size of sand. I can't wait to roll some comp around them and try one.

[Caramanos2000]

Does anyone have any tips on how to turn those cheap crackle balls or paper crackling fuse into some cool stars? I do have a general idea, but have any of you guys done it before?

[pudidotdk]

Use the dragon eggs as round star cores, or mix with damp compositon and pump comets.

[Bonny]

Sorry to bump a really old one here, but I have a question about the prime used on the flash core stars brother john listed

Barium Nitrate 66

Aluminum, flake, dark, German Blackhead. 3 micron 27

Dextrin 6

Boric Acid 1

 

The prime I found is this:

 

Brilliant core coating composition

Source: Composition from Shimizu[1], page 219.

Comments: This composition can be used to prime the 'Brilliant Core' stars (see effect stars). roll the cores in this prime untill they are round.

Preparation:

 

Potassium perchlorate.............................33

Barium nitrate....................................34

Aluminum (fine flake).............................10

Rosin (BL combustion agent).......................8

Antimony trisulfude (or sulfur)...................9

Boric acid........................................1

Soluble glutinous rice starch.....................5

 

Could the rosin be replaced with shellac or red gum? I don't have any rosin...

[Miech]

True, but I don't think it would matter that much when used in a priming composition. Especially when the brilliant cores are used with a streamer rolled around it you probably wouldn't see it if you knew.

 

I'd just give it a try.

[Zmuro]

True, but I don't think it would matter that much when used in a priming composition. Especially when the brilliant cores are used with a streamer rolled around it you probably wouldn't see it if you knew.

 

I'd just give it a try.

 

I use potassium nitrate based FP with bight Al and they work fine, I don't use any boric acid because Al is coated with stearine and I stop rolling when they are about 5mm . I prime them with BP+5% Bright Al and than I roll TT or C8 composition over it.