633 replies to this topic

[seymour]

There is a risk of auto-ignition?

Yes.

Ammonium chlorate is formed which is very happy to ignite or explode on contact with fuels, or for no reason at all.

A reputable pyrotechnics source, from memory I think it was Passfire, had an incompatibility list, and described actions that can be taken to make them safe.

For example it is quite safe to roll a sulfur containing composition over a chlorate star if there is a layer in between containing carbonates or other basic salts, so that acid cannot make it through to the chlorate.

Also, one can successfully roll Potassium nitrate over Ammonium perchlorate stars if there is a Potassium perchlorate based buffer bound with nitrocellulose in between.

However, with Ammonium salts and Chlorates, it was simply put that under no circumstances should they ever be in the same star, even with many barrier layers, it's not safe.

[Mnemotron]

That'll work excellently and it matches the blue I have made with CuCl2 - But the burning properties are better than mine since I rarely ever used hexamine (I used dextrin, PVC and shellac)! It seems like the hexamine is a bit high but perhaps the paper you lit it on is producing the orange tip in that video.

Good luck with your future devices.

Hi MDH,

This is my Cucl2 star test:
Do you think it's ok?.Thank you!

[lokys]

Hi,

Does anybody know some Red Strobe compositions without Ammonium Perchlorate ?? And does anybody had tryed it ??

thank's a lot!

[Creepin_pyro]

Hi,

Does anybody know some Red Strobe compositions without Ammonium Perchlorate ?? And does anybody had tryed it ??

thank's a lot!

There are lots of red strobe compositions which use Strontium Nitrate, lots of formulas come up if you do a search here. Here's a random one.

Strontium Nitrate 68.87%
Magnalium, granular, -100 mesh 22.50%
Parlon 3.44%
Dextrin 1.72%
Gum Arabic 1.72%
Copper(II) Oxide, black 0.87%
Copper(II) Oxychloride 0.87%
Bind with 10% NC lacquer

They don't tend to quite as good as AP-based strobes but you can certainly make something useable.

[lokys]

There are lots of red strobe compositions which use Strontium Nitrate, lots of formulas come up if you do a search here. Here's a random one.

Strontium Nitrate 68.87%
Magnalium, granular, -100 mesh 22.50%
Parlon 3.44%
Dextrin 1.72%
Gum Arabic 1.72%
Copper(II) Oxide, black 0.87%
Copper(II) Oxychloride 0.87%
Bind with 10% NC lacquer

They don't tend to quite as good as AP-based strobes but you can certainly make something useable.

thanks, I don't have Copper(II) Oxychloride and Gum Arabic, but I can change it to Red Gum.. Do you know what Copper(II) Oxychloride doing in this formula ?

I have tryed to find some compositions here, but I can't..

Edited by lokys, 11 January 2011 - 10:00 AM.

[Creepin_pyro]

thanks, I don't have Copper(II) Oxychloride and Gum Arabic, but I can change it to Red Gum.. Do you know what Copper(II) Oxychloride doing in this formula ?

I have tryed to find some compositions here, but I can't..

You can probably swap the Oxychloride for Oxide without much difference. Here are a few more from Llloyd on REC.PYRO:

Various Nitrate red strobes

Chemical #1 #2 #3 #3b
Strontium Nitrate 51 51 51 51
Sulfur 19 19 19 19
Parlon 5 11 16 16
Magnalium, 60 mesh 9 9 6 12
Magnalium, 200 mesh 9 3 6 0
Potassium Nitrate 7 7 7 7
Dextrin 4 4 0 0
Total 104 104 105 105

#3 and #3b bound with acetone, but try dex/water

#1 works particularly well, and by tuning the amount of 200-mesh vs.
60-mesh MgAl, you can speed the strobe up to a steady burn, or slow it
to one or two flashes per second, with an occasional "stop", followed
by self-relight.

This material works best simply "settled" in a 5/16" i.d. thin paper
tube (lance tube). Adding up to 3% air float charcoal will make it
less prone to go out, and easier to ignite.

It's not a "true" strobe, in that it has more of a shimmering,
intermittent burn than a regular on/off strobing.

Simply replacing the strontium nitrate with barium nitrate yields an
acceptable green version.

Please get "full official approval" for your activities, all the way
around -- school admin, parents, etc. I had a good friend who was a
high school honors chemistry teacher. He lost his career because two
boys built some devices at home, and blamed him for "teaching them
how". He was exhonerated, but his career is gone.

LLoyd

[Potassium chlorate]

I just tested Jennings-White#1:

ammonium perchlorate 70
hexamine 15
cupper(II)chloride 10
dextrin 5

Marvellous blue as a loose composition. Might be a very good star formula. Only drawback is the price of AP.

[Predator]

There are lots of red strobe compositions which use Strontium Nitrate, lots of formulas come up if you do a search here. Here's a random one.

Strontium Nitrate 68.87%
Magnalium, granular, -100 mesh 22.50%
Parlon 3.44%
Dextrin 1.72%
Gum Arabic 1.72%
Copper(II) Oxide, black 0.87%
Copper(II) Oxychloride 0.87%
Bind with 10% NC lacquer

They don't tend to quite as good as AP-based strobes but you can certainly make something useable.

what is the role of black Copper oxide in this composition?
why sulfur is not present here as many strobe formulas use it?

[Predator]

and why sulfur is not present here, many strobe compositions contains sulfur or metal sulphate in it.
Also dextrin & GA is present in this formula then why to bind this composition with NC?

[Tinderbox]

Anyone ever used Sodium Nitrate based stars? Pirotex over on APC has an absolutely magnificent yellow gold glitter formula. Hygroscopy though??!!

Doing this off my phone. No search facility on mobile version.

Edited by Tinderbox, 02 May 2017 - 11:09 PM.

[Tinderbox]

Here's his formula:

 

Name of composition: long lasting gold glitter

Composition Type: glitter

Creator: Pirotex

Color/Effect: dark charcoal tail with many flashing sparks 

Preparation: Pump with water or 25% alcohol in water

 

NaNO3 - 47%

Charcoal (airfloat) - 40%

S - 6%

Dextrin - 7%

+10% magnalium (granulated 50-70 mesh)

 

[dave]

thats a really nice effect

[cooperman435]

I even went to look if I had any sodium nitrate and I'm embarrassed to say I'm lacking!

Really nice tail for a canister shell 😋

[Tinderbox]

Really want to try this but last few times I worked with NaNO3 it was hygro'. I should probs join that forum and ask how he gets around that problem.

[Rob.L.]

 

 

 

 

 

 

 

 

 

 

Barium Chlorate/Potassium Perchlorate star composition. % by weight.

 

BaClO3 58

KClO4 15

BaNO3 8

P.V.B. 8

P.V.C. 3

Parlon 8

 

Solvent: xylene 30

              Ethanol 60,

              Water 10 (all approx)

 

No prime yet, lights easy. 8mm.

 

Will tweak and do video.

 

Experimental composition, more tests needed.

 

Edit* Sorry folks I originally posted KClO3 but it was meant to be KClO4. Apologies.