8 replies to this topic

[Gary]

Hi,

I am thinking of making some flash-core stars for use in mines, candles and star-shells.
Picture this: a coloured star, let's say, green, is ejected from the shell/candle. It completes its burn, then gives a white flash at the end.
I have several ideas for making these stars, one of which involves making a 1.5-2 cm diameter pumped star, allowing it to dry, then boring a hole in the centre. This hole could be filled with a flash composition.
The other involves a pill-box star filled at one end with a small quantity of flash comp.
I am also interested in making colour-change stars.

Any ideas would be appreaciated.

Thanks,

Gary

[Caramanos2000]

I have also thought of this, sound great. My idea would be to bind some 70/30 flash with dextrin(gets rock hard) and roll some regular star comp around it. You might get away with kno3/sulfur/al flash to lower cost.

[BrightStar]

Well, for mines and shells, I would pump the flash core composition to 5mm dameter. After drying, use these as cores and roll them in the colour comp in the usual way until up to size. You could use the Veline colours for example, which might be hot enough to ignite the flash core without an intermediate prime. The effect should be a brilliant white twinkle lasting about a second or so as the star burns out.

Name: Flash Core
Source: David Bleser (as listed on Passfire)
Barium Nitrate 66
Aluminum, flake, dark, German Blackhead. 3 micron 27
Dextrin 6
Boric Acid 1
Solvent: 50/50 water/alcohol

There's a reference to this (and the hot igniter prime if you need it) at Dan Creagan's site here

Edited by BrightStar, 19 February 2007 - 08:10 PM.

[portfire]

http://www.pyrosocie...p;hl=crossettes

Also search for comets and search the star formulas topic

[Gary]

I have also thought of this, sound great. My idea would be to bind some 70/30 flash with dextrin(gets rock hard) and roll some regular star comp around it. You might get away with kno3/sulfur/al flash to lower cost.

Would a flash comp. mixed and bound with dextrin binder still retain its flash effect, or would it just burn with a blinding white light for a few seconds?
Give it a try, it might work.
What about a using a dragon's egg comp. the size of a small marble, then rolling the star comp. around it?
It would probably flash, accompanied by a deafingly loud bang!
Even the tiny dragon's eggs microgranules produce a very loud pop when subjected to flame.

[karlfoxman]

2" Cylinder shell with stars - reports

Bit like this idea? I was testing breaks for cylinder 2" shells and my lavender and lemon colours, the camera did not pick up the lovely colour but you get the idea.

[Caramanos2000]

THATS BRILLIANT! How you do that? Oh, the Dextrin idea, I was hoping the Dextrin would cause the flash to burst because it become self confined.

[karlfoxman]

The inserts are little tubes 35mm long and 11mm od, id 9mm. These have some star composition pressed into them as a delay. You then add about 0.6g flash to each one, I used a red flash formula in these. The end is then sealed with an end plug. they were lined up along the wall of the shell and the remaining space filled with my homemade lift pulverone. The one with 1g flash broke the best the other had no flash. Each insert is nosed and has blackmatch to ensure ignition. Lift was 10g home made lift and the weight of shell was 98g. The time fuse delay was 10mm Portuguese fuse so it give a slight tail. The cases were Gamon 2" plastic cylinders.

[pyrotrev]

If one was to use a fast burning star mix you could have go-getters > reports!.