hst45

The one from last year? Or from the year before that, or the year before that........... I REALLY should tend to the brush pile.

Try this link for some info:

http://www.sciencema...;page=1#pid1002

It's surprisingly simple. I haven't tried it with strontium, but it does work with barium carbonate.

In my experience it has more to do with the quality and size of the charcoal than with the wood species. I made a bunch of rockets with newsprint charcoal, and they were very inconsistant. Now I'm using hardwood, mostly maple, charcoal and it seems much better. It gives nice sparky trails, and good, consistant impulse. I guess the answer is that if you take willow, balsa or any other "superior" wood, but process it improperly it would probably be inferior to pine or hardwood that is cooked better. Only experimentation will tell.

By the way, I use a good bit of white pine charcoal (the wood scavenged from wood trim at jobsites) and it works quite well, so pine should be fine to use. Good luck!

MDH, if your goal is a green-burning, simple fountain or rocket fuel, try 2 parts Zinc and 1 part Sulfur. It burns with a light green hue, produces a lot of smoke, and is much less toxic than barium compounds. It will be a washed-out green though.

But one last question that refers to ignitors.
---for my smallest cannons, I need a electrical igniter that will fit in 1mm hole.---

Wow, that's tiny. Could you could fill the "flash" hole with, well, flash, and tape the igniter on top? I suppose really fine grained BP dust could be made to work also. Pauls idea of blackmatch thread seems promising, but I'm not sure that it might not be stiff enough to push into the hole without bending and binding up.