Aerial Shells

[smed9182]

Also hold off on pasting the shell with the fiberglass tape or paper until the seam is completely dry. You don't make it clear how long you wait before doing this. If you do it imediately, you might be trapping the solvent in there, and causing a weak seam.

 

If you don't already, try using a tissue paper liner to keep the burst separated from the stars. Use a passfire of some sort to pipe the fire from the timefuse to the center of the shell. This drastically improved bursts for me.

 

You are right, the solvent not being able to dry may be part of the problem actually, I usually start taping the shell or pasting it in a few minutes after I apply the xylene. And I do use tissue paper and a passfire, sorry I did not mention that. I line the stars along the shell, and than place tissue paper in and fill with my burst charge. My pass fire tube consists of a thin rolled kraft tube that I attach to the time fuse and fill with meal.

 

For booster, I use 70:30 slow flash made with -350 Bright flake, not dark - I think the slower speed helps with star ignition and perhaps helps prevent shattering of the stars. A 4in usually gets 5g loose in the center of the burst and worked in with a chopstick.

 

I unfortunately do not have any bright flake aluminum at this time. Do you think that 7:3 flash with dark Al is too powerful in general? I've tried a nitrate based flash before with mixed results. The ratio was 2:1:1 KNO3,S, Dark Al. I used that in two 4 inch shells and one broke way too hard, and the other not hard enough, just a poof. I used around 18 grams of this flash as described in the 4 inch shell tutorial on skylighter (http://www.skylighter.com/fireworks/how-to-make/4-inch-ball-shell.asp)

Would a slightly stronger nitrate based flash give me close to the same potency as the 7:3 with bright Al? The ratio for that is 5:3:2 KNO3,S,Dark Al.

Thanks.

[Arte valdo]

4'' shell tiger tail to half red half green:

http://www.youtube.com/watch?v=cBWs0yyZGiQ

[qwezxc12]

I unfortunately do not have any bright flake aluminum at this time. Do you think that 7:3 flash with dark Al is too powerful in general? I've tried a nitrate based flash before with mixed results. The ratio was 2:1:1 KNO3,S, Dark Al. I used that in two 4 inch shells and one broke way too hard, and the other not hard enough, just a poof. I used around 18 grams of this flash as described in the 4 inch shell tutorial on skylighter (http://www.skylighter.com/fireworks/how-to-make/4-inch-ball-shell.asp)

Would a slightly stronger nitrate based flash give me close to the same potency as the 7:3 with bright Al? The ratio for that is 5:3:2 KNO3,S,Dark Al.

Thanks.

 

smed,

I think the 'sweet spot' is smaller when using dark flash for a booster; I tried it and found that my shells weren't very consistent and the break was too violent. For me, bright flake flash as a booster is more forgiving. It's also much cheaper as the Al from Hawk Mtn works just fine. I cannot give an answer based on experience with the 2:1:1, as I've never used it.

 

My way is just that: one of many ways to skin this particular cat. I went this route after trying various mixes of whistle and/or flashbags and booster, fast and slow BP on carrier, KP on carrier, different methods of pasting or none, etc. I bought a case each of 4in (250) and 6in (100) plastic shells from Pyrocasings, and using them I've dialed in my shells so that I no longer have to spend time tweaking the mechanics of the shell lift, timing and break. I get to spend my time trying new formulas and effects because I have a reasonable baseline for shell performance....and to me, that's much more fun.

 

Take copious notes as you change shell construction parameters; sooner or later you'll hit on a method that works for you.

 

Damn I hope my next shell is as good as yours was for the lady screaming in the background, lol. Nice shell man, that purple was beautiful. AP yes?

 

 

swervedriver,

Thanks. Yes it is AP/Hexamine blue. It was really quite blue; any purple cast must be from the camera.

Edited May 16, 2009 by qwezxc12

[swervedriver]

Good one Arte!

 

Smed, fwiw I use standard 7:3 indian dark flash for boost most of the time, and it works fine in my small 3-4" shells. This shell was made and fired yesterday to test some stars. It's just a 3" plastic round shell sealed with methylene chloride, then sealed with pvc glue around the closed seam for added measure. This dried for a few hours and then was taped with strapping tape. It's boosted with 1.8g of 7:3 standard flash in the center and poked down into BP on vermiculite carrier.

For 4" shells I use between 3 and 7g, and 3" between 1.5 and 3.5g depending on the type of stars, but I've broken small willow shells fine with just straight BP +RG pulverone. 7:3 flash is somewhat touchy I've found, adding a little more and it makes a big difference. I like to use whistle mix for boost too, it's easier on the stars they say. I prime stars heavy because, like yourself, I get bummed when they don't work right.

The vermiculite is sprayed and coated until it won't hold anymore BP, very scientific-like . My camera sucks and won't show the green colors, but you can see it's a decent break with standard flash used. Maybe it's your BP burst, your lift seems to be fine.

I'm just throwing this around, probably a silly question, but is your burst made with good milled BP?

 

Anyhow, here's the crappy vid of a 7:3 flash broken plastic shell-

 

Edited May 16, 2009 by swervedriver

[smed9182]

Maybe it's your BP burst, your lift seems to be fine.

I'm just throwing this around, probably a silly question, but is your burst made with good milled BP?

 

My lift charge is made with the same Meal that I use to coat rice hulls. I use KNO3 and mixed hardwood charcoal from highqualitychems.com and the sulfur is just 95% or something gardening sulfur. I mill my BP in a Chicago Tools dual drum ball mill for about 24 hours minimum. I coat my hulls in a 4:1 ratio, spraying the hulls until they are wet then slowly adding meal until they are all coated evenly.

 

As a lot of you guys have stated, it could very well be that my stars just are not primed enough and blow blind when the break is seemingly too hard. I think I'm going to look into that glue you were talking about qwezxc, and follow mumble's advice in letting the shell dry for a long enough time before doing anything else to it.

[Yankie]

Wow, if your getting breaks like that with out pasting swervedriver, I may quit pasting and use a more powerful booster than whistle. I have a fair bit of bright flake Al left so I can use bright flake Al. Now to order more plastic hemis... What will I do with all the paper hemis I ordered?

[yellowcard]

Make shells with them ofcourse . Just get a 3-4 layer pasting on your 3'' and use 7-1010g slowflash or 3-4g hotflash. Prime your stars decent. Your breaks will be fine.

[Yankie]

Ahh but pasting is such a PITA

I have a kilo or so of random shitty stars in a jar, ranging in effects from charcoal streamer, to glitter, to silver streamer, to coloured stars and even some crackling stars (I call it the poo star jar). I am wondering whether to put them all in a 6" shell or in a 5" mine....

Also I made 500g blue, 550g purple, 1kg red and 1kg green star composition. My star plate is gonna get a working.

Edited May 17, 2009 by Yankie

[swervedriver]

Yankie, I know a lot of the old school pyros here frown on the quick non-pasted flash-boosted plastic shells. But for myself, it's more the Ends than the Means.

I'm trying a 4" plastic double petal peony. The 2" inner petal has a small 1g dark flash boost while the outer petal is whistle boosted. I wonder if it will work or not, lol, we'll see...

[psyco_1322]

This is my post from Passfire, it covers my part of this break discussion:

 

I think it's amazing no one has mentioned whistle as a booster yet. I used it primarily over flash for my shells.

 

I break my 3" balls with bp rice hulls and 3g of whistle. The break plenty hard, and I have even considered backing off a bit to mellow out the break.

 

Been testing some 4" balls to dial in my breaks. I have been using bp rice hulls with 6g of whistle to boost. They seem to be breaking nice and hard. I might leave them right where they are.

 

Whistle is way cheaper, less sensitive, and a lot less messy than flash. Plus it doesn't leave blinding centers in your flowers

 

Because Lee will likely ask where I pulled my numbers from: I like my 3g in a 3", and thought that doubling the number sounds about right for booster amounts, plus it's simple to remember. This is what my numbers should look like on larger shells.

3" - 3g

4" - 6g

5" - 12g

6" - 24g

7" - 48g

8" - 96g

 

Yes, 100g of whistle in an 8" shell is going to be a bit over kill. I think I might omit the 7" shell from the series and use 48g in an 8". Future testing when I get to those sizes may dominate the final amount that I use. This is just an idea in my head right now and its not any farther than 4".

[Miech]

Smaller shells require relatively more booster than larger ones, so just doubling the amount for each inch probably isn't the way to go. By example, a 12" would need 1200 grams of booster this way, which is rediculously much. Anything from 6" should break perfectly fine without booster if you use a decent break charge and decent pasting.

[psyco_1322]

Actually a 12" shell would use 384g of booster if I was to stick to the pattern. I was only incorporating the sizes that are common, that's why I think I will throw out the 7". I still don't know how well this pattern will work with larger things, there may need to be a variation sometime. Until I can test it, I can't say for sure.

 

I have my final 4" ball test about ready. Should be a nice one, it's a straight Win20 shell - gonna be purdy.

[swervedriver]

Well the 4" double petal turned into a 4" with pistil. The 4" outer shell broke nice and big with whistle boost, but the inner petal didn't break big, nor round. Hmmm, these are hard to do well. Back to the drawing board on that one I guess..

[FREAKYDUTCHMEN]

Whistle should whistle, I've never seen a commercial shell with a whistle break so why should I use it.

6 grams whistle break simply can't beat my 5 grams hotflash or KP break.

[Mumbles]

There are a lot of techniques we use that are not commercially viable or economical. Just because it isn't used commercially, doesn't mean that it's not useful or valid. It'd be rare to find any commercially produced canister shells in the traditional techniques anymore.

 

Whistle has it's uses in burst strengthening. It doesn't produce as bright of a flash, which is advantageous in certain shells, as well as breaking crossettes. I've never noticed a distinct flash with FP when it is mixed into the burst, only when a flash bag is used however, so this may be a moot point. It still is nicer in crossettes IMO though for those of us who want to stay away from rolled shots of dark flash.

 

I think you will have issues making a 4" double petal that does not look like a pistil. Heck, I can barely get them to work with 6" shells. Keep working on it, I've seen very nice 4" double petals. You might want to try a thinner paper inner hemi for the inner petal if you did not use one. 2-3 layers of paper pasted over a 2" plastic hemi probably would work. It would allow for a little more room for the burst, and help give some more symmetry. I have a few more things I want to try before advising them, such as wrapping the inner petal with string as outlined (sort of) in Shimizu.

[smed9182]

So I've listened to everyone's tips on how to improve my shells, and I must say that it worked great! Here is my shell that I fired tonight, It's a 4" plastic Tiger Tail shell. I sealed it with xylene and let it dry much longer this time, then I taped it with the fiberglass reinforced gummed tape as qwezxc describes using 3 overlapping layers. The stars were 1/2" pumped Tiger Tail stars that I primed much more then I used to. For my break, I used 4:1 BP on Rice Hulls, with 5g of 7:3 perc/dark Al flash that I mixed into the break charge as Mumbles' said. The shell weighed 295 grams, and I used 40 grams of pulverone to lift it. I attached a couple slow gold comets on the shell, but my camera man did not do so well capturing it. This along with my other shell was filmed at about 350 feet away. It's not perfect yet, but it is definitely a start!

 

[Mumbles]

That was a mighty fine shell, and a good improvement. I'm glad we could help, and didn't steer you in the wrong direction

[swervedriver]

Beautiful shell Smed! Gotta love charcoal streamers, simple yet awesome.

[Aimlesspayload]

Would someone mind watching this video of mine and telling me if you think I'm having stars getting blown blind? the only ones you can really judge are the tiger tail and chrysanthemum #6 shells. The crackling and jumping jack shells aren't symmetrically arranged so...

 

-shells A, B, and G

 

http://www.youtube.com/watch?v=lWEIK-fWBwU

 

-thanks in advance for any replies.

Edited May 22, 2009 by Aimlesspayload

[TheSidewinder]

G looked like it may have blown some blind but A looked quite good, assuming you intended it to be a Spider shell. (The break was relatively gentle and the streamers all "dropped" from the point of break, as they should in a Spider.)

 

B was similar to A, though with a bit less streamer effect. Were those 2 built identically?

 

 

If those were your first shells of that size, you did a darn good job.

[Mumbles]

I think you may be confused as to what a spider shell is supposed to do. They are designed to be broken extremely hard. Large flash bag hard. They are supposed to be shot fast and in a straight line, when several are fired in tandem, the overlapping "arms" should look like a spider web. I do find it more pleasing to break the "big spider" of a timed spider shell soft like that. I think it looks kind of like a big spider (animal) within the webs.

[Aimlesspayload]

A and B were built similarly (A = pumped TT stars, B = cut TT stars), I pasted them with electrical tape basically in a halo around the seam of the plastic shells, so that the hemis would come apart easily. With G, I used chrysanthemum #6 cut stars, the thing is, I'm not sure if stars got blow blind because the time fuse was not set to light the BP from the center of the shell. I'm thinking all the stars ignited, but the stars nearest the initial burst-charge-ignition-point were thrown with less force than the stars farther from the ignition point? Think that's a correct guess?

 

I had made 4 shells before these. thanks for the compliment!

[TheSidewinder]

OK, I have my terms wrong.

 

What is the right name for a softly-broken shell where the streamers just drop from the break point, forming a "fan" about 30-45 degrees wide as they fall?

 

I've seen them shot by the volley, and the effect was beautiful.

[Ventsi]

SideWinder those are usually reffered to as horsetail or hosebreak shells.

 

These right?:

[optimus]

I thought horsetail shells broke on the way up, just before apex - creating an arc?

 

Great example of what I'm talking about at 6:00 in this clip: