Jump to content


Photo

Strobing


  • Please log in to reply
114 replies to this topic

#91 cplmac

cplmac

    Member

  • General Public Members
  • PipPip
  • 194 posts

Posted 25 February 2007 - 07:28 AM

There's three oxidizers in that formula Mumbles! Potassium Dichromate I believe converts to oxygen when it burns.

#92 seymour

seymour

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 691 posts

Posted 25 February 2007 - 09:24 AM

Indeed, but that is not Pot. dichromate's primary use in that type of composition, as is theprimary use of Ammon. perc and the sulphate in the two phases of the AP/sulphate strobes burning.
The monkey leaped off it's sunny perch and flew off into the night sky.

#93 Mumbles

Mumbles

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 955 posts

Posted 25 February 2007 - 06:29 PM

Yes, the strobing would still work, though not as effectively, without the dichromate. It is added for 1 of 2 reasons. Either it is there to help protect the Mg, or to catalyse the decomposition of the perchlorate. Might be a bit of both. It should be noted that the Mg should be coated reguardless or not of any extra dichromate added to the composition.

#94 Pretty green flames

Pretty green flames

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 689 posts

Posted 09 March 2008 - 07:41 AM

Does anyone know which prime is reccomended for Blesser's white strobe stars. Will a simple dusting of green mix do or am I going to need a serious prime to get these going?

Thanks

#95 Yugen-biki

Yugen-biki

    Pyro is forever

  • General Public Members
  • PipPipPip
  • 384 posts

Posted 09 March 2008 - 07:23 PM

Don't prime with green mix! The KNO3 and NH4ClO4 woll form NH4NO3 which is hygroscopic and your stars will not ignite and maby something worse. Use NaNO3 instead or find a strobe prime mix. The strobe primes I have tried all needed an additional prime. Try NaNO3 "BP" with 10 additional % fine (flash) Al.
Lancaster has a "ignitor" primer that I find interesting. It could be an alternative...

Edited by Yugen-biki, 09 March 2008 - 07:26 PM.


#96 Pretty green flames

Pretty green flames

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 689 posts

Posted 09 March 2008 - 07:35 PM

Blesser's white strobe as in

Barium Nitrate 51 grams
Potassium Nitrate 7 grams
Sulfur 19 grams
Magnalium 60 to100 mesh 18 grams
Dextrin 5 grams

My mistake, should've posted a formula in the first place. :)

#97 pyromaniac303

pyromaniac303

    Member

  • UKPS Members
  • 632 posts

Posted 09 March 2008 - 08:47 PM

I just step prime with 50/50 meal:strobe comp, then an additional layer of meal. Got 100% ignition, though I should warn you they burn for a long duration, hope you made them 5mm or smaller or it will be raining stars!
You can never have a long enough fuse...

#98 Pretty green flames

Pretty green flames

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 689 posts

Posted 10 March 2008 - 05:56 AM

I just step prime with 50/50 meal:strobe comp, then an additional layer of meal. Got 100% ignition, though I should warn you they burn for a long duration, hope you made them 5mm or smaller or it will be raining stars!


Cool, i've step primed them and they seem to ignite just fine in a star gun. But I did make them 10mm cut stars, a 5x5mm piece seems to have a burn time around 1.5secs which isn't too much. I think I've used too fine mesh magnalium so they burn that fastand don't strobe much, the strobe is very fast :(

See for yourself, a 5mm cube on the ground
Kinda pathetic I know.

I milled all the chems, sans the magnalium, together for 1 hour, should I pre-mill everything and screen together?

Thanks for your help

#99 MDH

MDH

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 742 posts

Posted 11 March 2008 - 01:56 AM

Hello there,

Just wondering how the Barium Nitrate, Sulfur and coarse Magnesium strobe is...

3 Barium Nitrate
2 Magnesium (40-60 mesh)
5 Sulfur

A good strobe?

Edited by MDH, 11 March 2008 - 01:56 AM.


#100 treefingers

treefingers

    Member

  • General Public Members
  • PipPip
  • 80 posts

Posted 24 March 2008 - 03:53 PM

I'm thinking about making Blesser White Strobe Stars but adding Titanium to the formula for a tail. Do any of you know if there'll be any chemical incompatibilities?
There is a very fine line between “hobby” and “mental illness.

#101 GalFisk

GalFisk

    Member

  • General Public Members
  • PipPip
  • 39 posts

Posted 26 March 2008 - 12:11 PM

Ti is not chemically incompatible with other pyro ingredients, but it can increase the friction sensitivity of comps.

#102 Bonny

Bonny

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 538 posts

Posted 03 June 2008 - 01:27 PM

Blesser's white strobe as in

Barium Nitrate 51 grams
Potassium Nitrate 7 grams
Sulfur 19 grams
Magnalium 60 to100 mesh 18 grams
Dextrin 5 grams

My mistake, should've posted a formula in the first place. :)



I made a batch of cut stars using this formula. They strobed nicely on the ground, but when fired in a 3" ball shell, they just looked like white stars... Is this normal? Maybe they strobed too fast for the eye to see at a distance?

#103 Mumbles

Mumbles

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 955 posts

Posted 05 June 2008 - 04:34 AM

I'd be worried the Ti would kill the strobe reaction by making it burn too hot, and thus killing the dual reaction (dark and light reactions). The chems arn't too expensive though, so it never hurts to try. If it works, it would be an absolutely beautiful comp.

#104 drtoivowillmann

drtoivowillmann

    Member

  • General Public Members
  • PipPip
  • 36 posts

Posted 02 September 2009 - 02:10 PM

Gentlemen:

I am a professional fireworker since about 20 years an a Ph.D em Chemistry. But from my youth, when fireworks were only my hobby, I have some extremely cheap exotic strobe star formula. They are only to amateurs, but useless to professionals who have to make large quantities.
They do use laboratorium grade very coarse magnesium (for the so called Grignard-reactions) instead of magnalium and laboratorium grade charcoal (whithout any contamination of bronze particles, present in many factories ball mills, which might degrade the magnesium):

white: 90 parts Potassium Nitrate; 11,5 to 13 parts coarse charcoal; 5 parts carboximetylcelulose powder (binder); 3 to 5 parts magnesium
(mesh 2 to 10)
red: a) 80 to 85 parts Strontium Nitrate; 13 parts charcoal; 10 to 15 parts Potassium Perchlorate; 3 parts magnesium; 2 parts
carboximethylcelulose
B) 60 parts Strontium Nitrate; 35 parts Potassium Nitrate; 13 parts charcoal; 3 parts magnesium; 3 carboximethylcelulose
green: 80 to 85 parts Barium Nitrate; 10 parts Potassium Perchlorate; 13 parts charcoal; 3 to 5 parts magnesium; 5 parts carboximethylcelulose
yellow: 80 parts Sodium Nitrate; 13 parts charcoal; 3 parts magnesium; 3 carboximethylcelulose

* moisten with destilled water, make cut stars, prime with simple Black Powder
* only work as stars, do not work in lance work or flares
* the relatively small amount of coarse charcoal only reduces little of the nitrate oxidizer and slowly melts it down. When the molten zone
arrieves a single of the coarse magnesium particles, it explodes with a bright flash. The large number of repeated explosions of the coarse
magnesium particles produces a beautyful strobe effect in the sky, however without any stability of its frequency. Se secret is in the particle size
of magnesium. If it were to fine there is only continous burning.

Don't believe, simply try it. As you see, theese are not so dangerous formulas.

Greetings :

Toivo

#105 pyrotrev

pyrotrev

    Pyro Forum Top Trump

  • UKPS Members
  • 1,112 posts

Posted 07 September 2009 - 12:33 PM

Hi Toivo - thanks for the formulas - do you know the approximate size of the magnesium particles please?
Trying to do something very beautiful but very dangerous very safely....




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users