should paper cylinder shells blow out sidewalls or just end caps

[jakespeed]

followed skylighter's instructions to the T from http://www.skylighter.com/fireworks/Paper-Cylindrical-Shell-Rocket-Heading.asp

 

only difference was i used a 1/4" timed fuse & shot it from a mortar

 

only got endcap blowouts which looked ok, but not what i was expecting

 

[lloyd]

Jake,

IF only the endcaps blew out, then you did not either 1) properly paste in the endcaps, or 2) did not properly burst the shell.

 

Although it's a "cylinder", still, it should burst more-or-less symmetrically about ALL centers of axes.

 

Lloyd

[pyroman2498]

A normal shell is supposed to blow to pieces, or at-least that is how i have found the fallout from my shells to be.
I agree with Lloyd above and would also add , spiking it should help also. i dont anymore tinker with these smaller shells but when i use to i always spiked them. Even with my pretty bad BP at the time i would get the shell to blow into smaller bits.

Stay Safe and Stay Green,

 

~Steven

[Mumbles]

I've never tried spiking and pasting a shell with only reinforced gummed tape. I'm more used to following general method: http://wichitabuggywhip.com/fireworks/2inchsalami.html The ends popping before the rest of the shell is usually called a horsetail break, but that has become a more confusing term, since it's also a popular intentional type of shell now. It typically comes from your reinforcement not being even.

 

If I'm following the skylighter tutorial correctly, it looks like there is one strip of reinforced tape for the casing, which has the fibers running around the circumference of the shell. Then when pasting/spiking the shell, there are two strips that run around the circumference, and one that runs the length of the shell vertically. The 3:1 ratio of horizontal to vertical strips would be where I'd start trying to trouble shoot. When you try another one, you might want to try to use 2 vertical and 1 horizonal strip when pasting so the number of layers for each direction are even.

 

 

Edit: I was mistaken. I misread the spiking/pasting portion and there is only one vertical and one horizontal layer there. You could possibly add a second vertical pass to reinforce that direction.

[jakespeed]

skylighter's 1-3/4" shell once wrapped was a bit tight in my 1.91" mortar

 

was fearful of blowing the mortar

 

so i made another @ 1-3/8" diameter

 

i only used 1 wrap of then thin cardboard instead of the suggested 2

 

i left the layers of fiber reinforced tape as recommended

 

this time it blew in all directions

 

once my 2" mortars arrive i'll give the 1-3/4" shell another shot with less thin cardboard

[lloyd]

Jake,

ANY shell should explode in "All Directions", unless it's a ring or pattern shell!

 

Think about it -- you'll laugh!

 

Lloyd

[schroedinger]

^^ lloyd, and whats with horsetail shells?

[lloyd]

^^ Shroe, it's a 'pattern shell'.

 

Ask yourself if the name gives away what pattern it makes in the sky.

 

LLoyd

[OldMarine]

Here's a nice horse tail:

[schroedinger]

^^ Shroe, it's a 'pattern shell'.

 

Ask yourself if the name gives away what pattern it makes in the sky.

 

LLoyd

Maybe next time i better put [ironic] .... [/ironic] Edited May 12, 2016 by schroedinger

[lloyd]

Sorry if I missed your meaning.

I just got finished reading a 'treatise' here about "polverone", where, since the writer can't _personally_ find a place in his vocabulary for a particular mixture, he's decided to usurp the old, traditional (yea, even 'standard') term. He knocks mortar out of the joints of this art's foundation with each such malapropism.

I get increasingly weary of people who deliberately diminish this art through misinformation, to such an extent that I'm really sensitive to the matter.

 

That sometimes makes me miss (attempts at) humor! <G>

 

LLoyd

[Arthur]

The break pattern is part of your shell design! You design what you want and then you make it. Horsetail is one pattern, Bow Tie is another ball is another - there are probably more patterns before you get to multi petal designs.

The physical arrangement of the components in the casing and the design of the case and the burst all affect the style of the shell break in the sky.

Horse tail is a great effect if you do it well but a simple star dump looks no good. Having the formula is only 10% of having the shell design.

[MrB]

While on the topic... The bowtie, i tend to over-break, and use fast burning stars to leave a short flightpath, with high density spark trails behind. I guess they could just as well just be broken hard enough to burst the endcaps, and leave the cylinder structure intact?

 

And both bowties,and horse tails need to be oriented properly for the audience to get the whole picture. It's easy enough to add drag to get them to orient right on one axis, but getting them to be parallel with the audience so they see the full effect...Impossible. So i just shot a bunch at the time, and hope that at least some shows of the effect in the right way. This is mostly true for "all" pattern shells, of course.

B!

[schroedinger]

B! For a bowtie shell, just use a round shell,

[MrB]

I guess that works to. Leaves the same issue orientating the shell anyway.

B!

[dagabu]

Sorry if I missed your meaning.

 

I just got finished reading a 'treatise' here about "polverone", where, since the writer can't _personally_ find a place in his vocabulary for a particular mixture, he's decided to usurp the old, traditional (yea, even 'standard') term. He knocks mortar out of the joints of this art's foundation with each such malapropism.

 

I get increasingly weary of people who deliberately diminish this art through misinformation, to such an extent that I'm really sensitive to the matter.

 

That sometimes makes me miss (attempts at) humor! <G>

 

LLoyd

 

I didn't read any misinformation in that thread.

[schroedinger]

B! a round bowtieshell also looks really like a bowtie. If you use a finn arrangement for orienting the shell, you can orient two of the axes, but the third will always be 360º luck.

If you have a flat pattern shell, i would use an angling of 30-40º as it will be recognizable at about 280º of the y axis (with an opt. Of about 40º).

A ring an bowtie from a round shell doesnt have that problem, it has just about 40º of bad orientatiation.

[Bangkokpyro]

Jake,

ANY shell should explode in "All Directions", unless it's a ring or pattern shell!

 

Think about it -- you'll laugh!

 

Lloyd

Or Maltese.

[lloyd]

Yeah, but Paul, Maltese-style shells are just (after all) multi-break ring pattern shells!

 

Lloyd

[Peret]

A good horsetail needs careful timing, with the fuse cut longer so that it breaks at the apex, as it turns over, and preferably shoots the stars out horizontal. If it breaks on the way up it looks like a failure, not a horsetail.

[stix]

followed skylighter's instructions to the T from http://www.skylighter.com/fireworks/Paper-Cylindrical-Shell-Rocket-Heading.asp

 

only difference was i used a 1/4" timed fuse & shot it from a mortar

 

only got endcap blowouts which looked ok, but not what i was expecting

 

 

Lloyd quoted:

Jake,

IF only the endcaps blew out, then you did not either 1) properly paste in the endcaps, or 2) did not properly burst the shell.

 

Although it's a "cylinder", still, it should burst more-or-less symmetrically about ALL centers of axes.

 

Thanks for posting this question Jake and the simple explanation from Lloyd - I've learned something valuable. Although I haven't made any shells yet, It was a question that I've wondered about. I did some searching on here and google but couldn't find an answer. Try googling "how does a pyro round ball shell break" ie. the actual mechanics of the break, and you'll understand the problem.

 

I was initially thinking that with a round shell the two hemi's simply parted ways at the weakest point, being the join. A CAN shell, I assumed must break in the center. A horse-tail was the only one I could be sure of what was actually going on.

 

So thanks again.

 

[EDIT] Also as pyroman2498 stated: "a normal shell is supposed to blow to pieces" - that says it all.

Edited May 22, 2016 by stix