1569 replies to this topic

[rocket]

That was one nice shell there mate, good job. Too me it looked like the rising comet went out and relit or maybe it fell off and was at its peek and started to fall.

Edited by rocket, 22 May 2007 - 06:40 AM.

[karlfoxman]

Suberb shell, Loved the break and the comet was timed perfectly! You got any construction pictures, would like to see inside the shell. The Veline stars lit well, how did you prime them, was it the same way I prime Veline?

[maxman]

Great shell BrightStar! Could you please describe how and what prime you used for your "step prime?"

[paul]

I can only admit what my previous speakers said! Amazing shell. I´m interested in the comet composition. A very thick and long lasting tail!

I especially like the breaks symmetry and the stars color which is exceptionally beautiful!

[pudi.dk]

Paul > says Tigertail on the shell, it looks like a Tigertail, so why wouldn't it be?

[Pyromaster2003]

That shell looked spot on did you add aluminium or ti to the stars? noticed they had a nice trail of white sparks...

[BrightStar]

Thanks for all the feedback folks.

Rocket, re the comet 're-ignition', frankly I have no idea. It was pressed into a cardboard canister before gluing it to the shell, so maybe a portion of it only ignited after the burst...

Karl, Maxman, construction pics below - I'm sure you can figure them out... When I first rolled the stars they were difficult to ignite so I used quite a generous prime. On 150g of the Veline red stars I rolled another 50g of 50/50 Veline red and willow meal screened together. The outer prime was 50g of 50/50 willow meal and green mix with +5% dextrin. I have had good success with this method with a variety of comps - it takes a little extra effort but seems to work.

Pyromaster. the Veline red contains 6% magnalium (I used 200-mesh) and the tail that you saw was simply the 50/50 step prime burning...

I'm now thinking of how I could make this shell in 9 or 10 different colours if only I had the facilites... a salvo of these would make an awesome finale to any show... Pics below:









As a quick disclaimer, I should add that this shell was constructed and tested in the open air in remote farmland far from harm's way...

Please feel free to ask any questions

// A few months after posting, I feel I must emphasise once again the safety aspect. The shell was constructed and tested in a remote agricultural location over a mile distant from other people. Please don't try this unless you have the space to work safely.

Edited by BrightStar, 01 August 2007 - 03:34 PM.

[Pyromaster2003]

Was a good effect im just starting to get into shells think your pics and vid got me inspired to try another shell lol! Only got one more question before i roll my next lot of stars...what cores did you use lead shot or other...? Thanks

[KarlosH]

Guestion: Which outer prime is the best for 100% ignition of stars??? Classic black powder75:15:10, or black powder wit more charcoal or more sulphur??? Thanks. Bye.

[Mumbles]

Neither of those will give you 100% ignition of all stars. I've been using this lately, with a layer of green meal over the top. Never had a star not light with this prime combo. I have broken the prime off the stars as I was "tapping" my shells shut though. I was really hammering on it though. I have some silicon I'd like to try out as well.

Potassium Perchlorate 55
Charcoal Airfloat 20
Wood Meal 6
Iron(III) Oxide, red 5
Potassium Dichromate 5
Magnalium, granular, -200 mesh 5
Dextrin 4

[BrightStar]

Hi Pyromaster - glad the shell inspired you. It sometimes seems a bit crazy to destroy 7 hours of work in 7 seconds but was worth it in the end. I did indeed use 1mm lead shot on this occasion. You only need a tiny amount - half a teaspoon produced 140 stars...

KarlosH - fast burning meal powder can often flash off a star without igniting it. A slower burning green mix (unmilled 75/15/10) is better. I've sometimes added some Crysanthemum 6 or Tigertail to my BP prime mix if I have it lying around - it also seems to work.

Mumbles - I have been thinking of making a universal prime mix for a while but don't much like the idea of carcinogenic dichromate in everything. I read here that copper oxychloride can also catalyse the perchlorate decomposition. Do you think it has potential for use in a prime or would it cause incompatibilities?

[Mumbles]

Just for personal reasons, I probabably wouldn't use it with copper oxychloride in conjunction with AP based stars, but thats about it. I have a feeling the dichromate is in there for dual use. One to catalyse the decomposition of the perchlorate, and the other to protect the MgAl. I don't believe the MgAl needs protection, but if the prime is used on a AP star, I could see it. Rather, another possibility would be to replace all the dichromate with Fe2O3.

[KarlosH]

Brightstar: Thanks. I have asked, because stars of my last shell was had bad ignition. I was used only black powder, but of cca 200 stars has burnt only small percentage. Another shells of my old tests was good....
I thinh that glossy surface of round stars is not so good for ignition, maybe small particles of burst charge hawe a small pneumatic interspace??? Maybe thin layer of dextrine which causes but ignition???
Sorry my english is not so good :-(
http://img02.picoodl...tam_8bc3d8d.jpg
http://n-joy.cz/vide...8Mn2TV82MfAhAU/

[Caramanos2000]

Just fired off a homemade canister shell from HDPE. my buggest yet. Used 3 Teaspoons of lift, shell was 2"x4"long, filled with 50/50 mg and bp with allot of red flying fish. Wow, it looked like I bought it, didnt use any flash but the bang was so loud! it flew to about 350' and blew perfectly. Will tape it asap.

[maxman]

Just wanted to share with you all a couple of 3 inch shells from last night.

The first was Tiger Tail It was beautiful!

The second was D1 Glitter I dont know why the break was odd because it was made the same as the tiger tail. They were Gamon ball shells glued and fibreglass tape strapped.

Hope you all enjoy anyhow

Any comments or advice welcome