tdpyro

All of the aluminium and magnalium stars that we have been making recently have been swelling and cracking, and then start crumbling and turn powder given a long enough time.

I have been reading a skylighter article http://www.skylighte...cle.asp?Item=60 on the problems that can arise with fireflly stars. It indicates that a acidic potassium nitrate can cause crumbling problems, when used with aluminium. Is it possible that this also causes problems with magnalium based stars. (Our Potassium nitrate is GD)

Has anyone had any experience with these problems?
Does anyone know of a solution to this?

Using sodium bicarbonate seems to neutralise the acid and protects the stars from this effect to some extent, for example our D1 stars do not have this problem. But a similar based composition with higher amount of magnalium are starting to crumble. Using sodium bicarbonate induces a yellow colour , and causes the delayed glitter effect. On the skylight of article it suggests using potassium bicarbonate (this would not cause the yellow colour), does anyone know where this would be available from?

What would be a good prime for ammonium perchlorate based stars without using AP itself? Also I do not have potassium dichromate which many prime compositions recommend for using with a potassium perchlorate.
Thanks for any help.

I have recently designed and built a Visco machine, it's just about complete, just a few more refinements to the pulleys and nc application. When its complete , I will upload photos and hopefully a video of the machine in action.

I was just wondering if any of you guys knew of some Visco compositions , other than standard meal?
Don't some types of Visco use a perchlorate based composition?
Ive used standard meal, which worked great, but it does not seem as aggressive as some of the commercial fuses (it doesn't fly all over the place like a little rocket engine).

Any help is appreciated.
Dave