633 replies to this topic

[rocket gary]

does any on have any good stars that use zinc powder as i have loads of it iv tryed some comps on pyro guide theres only 2 comps that i can find soo i thought some of you would have some better ones thanks all

[seymour]

What was wrong with granite stars, which I assume were the ones you saw on pyroguide.


I've made a number of formulas based on black powder with zinc and a binder. My old Zinc powder burned slowly in the mix:

BP 10 (50%)
Zn 9 (45%)
Dextrin 1 (5%)

My new Zinc, a finer powder, burns fast in the mix:

BP 7 (35%)
Zn 12 (60%)
Dextrin 1 (5%)



You can try the granite formula, or experiment like I have.
By the way, this thread is for posting and discussing existing formulas. While I can understand posting your question here, I believe it would be more suitable elsewhere.

[rocket gary]

ohh im sorry i didnt relise i could not ask a question the granite stars are ok but i find the burn very quick and i thought with zinc i could get long hangs thanks for your reply

[seymour]

Because of the fast burn, you will need to do what I did and change the ratios.

There are stars called "zinc spreader stars", which give a trail of burning zinc. However, these need pretty coarse zinc. Because your stuff burns so fast, I doubt it will work.

From memory, the Zinc spreaders were typically Potassium chlorate, Zinc, Potassium nitrate and Charcoal.

[rocket gary]

iv also made zinc spreader stars they are also ok im realy just looking for some thing to hang for as long as possible but they are a good effect thanks

[CCH Concepts]

I've made a zinc/sulfur comps mainly for smoke devices. but I'm sure this could be bound to make a decent star.

[portfire]

If your after a long hang-time try this

Name: Slow Gold

Source: Dave Buell

KNO3-36

C (airfloat)-29

C (80 mesh)-14

S-9

Ti sponge 40-80 mesh-7

Dextrin-5

Ball mill all apart from the 80# Charcoal and Ti, then screen. Long hang-time and a great effect

[Vic]

Slow gold is an absolute classic long hang time formula, Willow Diadem is an another but I don't now whether the formula is in the public domain.
Here is a video by Sasman showing both: My link

[CCH Concepts]

i love the density of those shells and the spread they get. how big does the shell need to be to get that effect only maybe smaller. i have a few 3" shells but not the tubes to fire them at the mo. will i be able to achieve a nice effect with shells sizes. what size stars should i uses and how would you suggests the break charge being implemented? i apologize if this is the wrong place for this quest just that video made me wounder.

[a_bab]

The absolute best charcoal for thick, long lasting sparks seems to be the one obtained from the black locust wood (Robinia pseudoacacia).

There are some very nice stories about it on the passfire forum, such as the sparks are so long lasting that they will fall on the earth even from 200 m of high. The stars should be something like 75% black locust/25% pine tree in order to avoid this (TT stars), and around 8 mm max for a 6" shell.

[seymour]

I find it quite amusing how much discussion of these compositions these there is, and the mythical status that seems to surround them.

I have made many similar formulas, and YOU WILL NOT get the same effect as someone else if you do not use exactly the same starting materials. So many variables exist, such as Titanium particle size (you may not have, nor do you need exactly 40-80 mesh), and charcoal type, and sulfur content. I've had a very similar composition in 20mm stars burning in two seconds, and then 11mm stars burning for over ten seconds.

Essentially, you are going to need to do some tweaking.

Adding more sulfur increases the delay of the titanium, and gives it a more shimmering quality.

Obviously the Charcoal will play a huge role, and if you use Locust, then I'd do what A_bab says. With Radiata pine charcoal, more sulfur than slow gold, and a little bit of sodium bicarb to slow it down even more, I had 9mm stars burning perfectly for a three inch shell.

CCH, you can definitely get a three inch shell working well with these stars, though obviously it will not be as dense as the bigger shells. Just burst them like you would any other chrysanthemum, if you want a chrysanthemum burst, or like a horsetail, if you want a horsetail break... We cannot tell you how to burst it, because that is a choice you need to make. By the way, Sasman's shells are chrysanthemums.

http://www.youtube.c...u/4/tHUlvblN9zI

And the firework in my youtube vid from 26 seconds to 40 seconds is a horsetail.

[Potassium chlorate]

Haha, I love your ironic "hobbies" on your YT profile.

Wonderful fireworks, mate!

[Vic]

i love the density of those shells and the spread they get. how big does the shell need to be to get that effect only maybe smaller. i have a few 3" shells but not the tubes to fire them at the mo. will i be able to achieve a nice effect with shells sizes. what size stars should i uses and how would you suggests the break charge being implemented? i apologize if this is the wrong place for this quest just that video made me wounder.

I would say your 3'' shells would be fine.
But I suggest you try some star formulas, make yourself a star gun and pump some stars say 3/8
you will be able to see the individual star effects achievable and at the same time you can get your lift up to scratch.
Start off slow and then see what it takes blow them blind adjust your prime if necessary then imagine them in your 3” shell,
and that will inspire you to learn the finer details of shell building.

[CCH Concepts]

i have just had wienarts book delivered (i know thats the wrong spelling), so hope for some good stuff in there.

i have had good results with valine stars and tiger tails so far, there the main ones i have used. until they fail me I'm pretty happy with them, saying that i likes the Yankee flashers so going to give them ago.
i am going to be trying other effects hummers, tourbillions effects like this look really cool.

another one i really want on concentrate on is my rockets. so alot here lol.

i have some brass now and I'm going to make some tooling, i want a crossett pump, but I'm thinking i might need to buy this, but ill give it a go at making one.

[Vic]

I find it quite amusing how much discussion of these compositions these there is, and the mythical status that seems to surround them.

I have made many similar formulas, and YOU WILL NOT get the same effect as someone else if you do not use exactly the same starting materials. So many variables exist, such as Titanium particle size (you may not have, nor do you need exactly 40-80 mesh), and charcoal type, and sulfur content. I've had a very similar composition in 20mm stars burning in two seconds, and then 11mm stars burning for over ten seconds.

Essentially, you are going to need to do some tweaking.

Adding more sulfur increases the delay of the titanium, and gives it a more shimmering quality.

Obviously the Charcoal will play a huge role, and if you use Locust, then I'd do what A_bab says. With Radiata pine charcoal, more sulfur than slow gold, and a little bit of sodium bicarb to slow it down even more, I had 9mm stars burning perfectly for a three inch shell.

CCH, you can definitely get a three inch shell working well with these stars, though obviously it will not be as dense as the bigger shells. Just burst them like you would any other chrysanthemum, if you want a chrysanthemum burst, or like a horsetail, if you want a horsetail break... We cannot tell you how to burst it, because that is a choice you need to make. By the way, Sasman's shells are chrysanthemums.

http://www.youtube.c...u/4/tHUlvblN9zI

And the firework in my youtube vid from 26 seconds to 40 seconds is a horsetail.

Semour could you explain the chrysanthemum effect my interpretation is longer burning stars that fall to the ground but Takeo Shimizu Chrysanthemum 6 is a Fast burning charcoal streamer no hang effect .