1569 replies to this topic

[RegimentalPyro]

Nice looking shell Paul.....

What are you going to use for lift and burst? [When you say things like "Flash break" I get jittery.....]

[paul]

Oh, ehm yes. With flash break I mean using about 2g of Flash as the main breakcharge and blackpowder on corncob mix as a filler.

Lift?! Hm, 15-20g blackpowder... These are willowshells. When they fly too high the effect seems pretty small, I think. Or are I?m wrong and should use more?!

[heinz]

Hello everybody.

I?ve seen a lot of nice shells around here, so I have to say
that I?m really impressed of some people's work.

Since this is my first post, I?d like to introduce my doings.
I?ve been in pyrotechnics for about one year now. I?ve
spended most of that time in making my own BP, testing
stars and building canister shells. Here is a little movie (14 MB),
containing everything I?ve managed to build for last
new year?s eve.

http://home.arcor.de...r2004_heinz.mpg

These are cylindrical shells, 50 - 100mm in diameter, some
of them with multiple breaks. At the end of the clip you can
see some small selfmade rockets and starmines, too.

To get back to topic - I?m an absolute beginner in building
spherical shells, so it is my pleasure to present my first two
4"-Shells to the audience:

http://home.arcor.de...er_Kugel_01.mpg
http://www.8ung.at/h...er_Kugel_02.mpg

The first one contained 64 pumped tigertail stars, with a
little additional Ti (10%). For the bursting charge I used
about 80g BP + 8g Mg (50?).
The shell was liftet to about 150m height using 25g BP.

The second one contained 150 pumped willow stars with
5% Ti added to the composition. Bursting charge was
BP+Mg again, height was about 120m using 16g BP
lifting charge. It also was my first attempt to attach two
ascending tigertails ,too. They burnt out a little to fast,
but they worked.

I?m planning to use some colored stars for my next shells,
maybe in combination with those charcoal stars you?ve seen
above. Now I?m a little unsure about the risk of using colored
stars, all containing KClO3, wich will be lined up next to the
charcoal stars containing Sulfur.
It is said that KClO3 together with S is always a risk and should
be avoided - but on the other hand in this case the KClO3 is
just part of a bounded composition using red gum.
So what do you guys say - is it a big risk putting a charcoal
star containing S next to a colored star containing KClO3 into a
spherical shell ? I don?t have any KClO4 avaiable, and it will take
some time until I?l be able to roll my stars with "safety-layers".

Greetings from Germany
Heinz

[broadsword]

WOW
Very Nice shells!

[ProfHawking]

WOW
Very Nice shells!

seconded!
amazing, especially that second 4" shell. I have to give titanium a go...

i'd say even if they are only your first attempt at sphericals, the effect is nicer than the canster ones. Great going!

[alany]

I've never seen Titanium glitter before, especially in a low-sulfur composition.

I'd love the composition of those transformation comets in the mines at the end of the big video.

[Richard H]

Heinz, would you mind sharing the willow formula you used in the second shell? It looks fantastic.

[sasman]

Very Tasty...As for that last shell...i got that effect from willow with 5% to 10% Ti added when i made some rolled stars in a hurry with Nc laquer that had not dried 100% ..

Also looking forward to Danniels Scotts dozen orso shells....

[Richard H]

Out of interest, what size mesh do people find titanium works well for in stars? 60-100, -100 mesh?

[paul]

First: Heinz, your shells are GREAT! I like this flashing effect of the Ti best.

Heinz, I think an last layer of charcoal/aluminium/KNO3 as the prime layer will do the trick.
The willow stars are ignited easily and so this mix will work for that purpose I think. So there would?nt be any contact between KClO3 and sulfur at all.

But then you have to clean up your mill, to not get any sulfur traces into the charcoal/kno3/(aluminium) mix.

[Yugen-biki]

Nice shells Heinz!

About the sulfur KClO3 problem:
When puting chlorate-stars or H3 with sulfur stars or break powder the shell gets sensitive to shocks. If the shell were to fall back on the ground or you wold drop it, the shell might go of.
If the shell would get moist or damp composition is used, the KClO3, or maby the sulfur, may leech out and mix the two chemicals. If the sulfur contains sulfuric acid the mix might take fire.
It is not very dangerous to put solid stars with other solid compositions when one uses S and the other KClO3. BUT no one does it just to avoid the problems stated above.
One way to seal of the stars and burst is to use silk-paper as a barrier.
When mixing different stars you do best in useing a prime to separate the incompatible compositions. A binder that makes a solid water tight seal is god when primeing stars like this. Because in this way you don't need to fear the KClO3 to leech out of the star and into a sulfur composition.

P.S.
I like the Ti stars very much! What mesh did you use?

[PyroKid]

Just a quick message to congratulae Heinz on some top-quality shells.
I have got to aggree that the spherical shells produced a better burst than the cylindrical shells, but saying that, cylindrical shells are renound for their somewhat random dispertion, while spherical shells are renound for their spherical "floral" bursts.

Keep up the good work!

[heinz]

Thanks for your replies

Heinz, would you mind sharing the willow formula you used in the second shell? It looks fantastic.

So here?s the formula for these willow-Ti stars,
it?s a charcoal firedust composition taken from Shimizu:

KNO3 35%
S 12%
C 45%
SGRS 08%

with additional
Ti 05%

I?ve used spherical Ti 250-500?m. The stars
need to be made by a wet process - so I?ve
used the CIA method as if making BP and then
pumped them.


Greetings
Heinz

[Phoenix]

Well worth the long download! Excellent work.

[Jerronimo]

Yes Heinz very nice work, got to get me some Ti .

That 2nd spherical shell just was amazing.
for another nice effect you could try these formulas:

Silver:

85 BP
15 spherical Al (around 250 mesh)
5 bariumsulfate

Gold willow:

80 crysantium6(shimizu)
20 spherical Al (around 250 mesh)

Keep up the good work!