22 replies to this topic

[50AE]

You know, sometimes I wonder if you guys have any practical experience with these warnings you're giving, or are just regurgitating stuff you've read.

I think that others will agree, some of us cannot or don't want to encounter "practical experiences" and prefer regurgitating stuff we've read.

[Mumbles]

I wasn't talking making kilos of composition, just to blow it up. Very small scale tests will give you reference point. A small scoop of chlorate, and a small scoop of sulfur into a mortar and pestle. Grind it together, and see what kind of pressure it takes. It won't blow up all at once, it normally gives small snaps and crackles. Even if it does go up, thats why we use the small scoops. Try the same thing with perchloratte. You will notice that it is harder to get the same snaps, but it's still not all that difficult to achieve.

I've never tested any other additives. I would use H3 as a control though. It is more or less fuel balanced. The addition of copper oxide, iron oxide, etc. will show the increase in sensitivity. I found it odd, from reference values, how sensitive lactose and chlorate is, despite it's wide use. That was impact though IIRC.

[50AE]

Yes, I did some test previously with potassium chlorate and some chemicals. KClO3 + Sulfur detonated with ease from the friction of the mortar and pestle. KClO3 + Sugar was almost insensitive, as well as KClO3 + CaSO4 + a little sugar. However, KClO3 + dextrin seemed to be very sensitive, not as the sulfur mix, but still.

[AdmiralDonSnider]

I agree that there is a tendency to overstate the dangers of using chlorate oxidizers. This is founded in the claims of many amateur resources around. Most exhibition fireworks are still widely based on chlorates. However the choice if to use chlorate is an individual decision.

I have also wondered if replacing the perchlorate with chlorate in some compositions with compatible reagents will work fine ?

Indeed. Replacing chlorate for perc 1:1 in e.g. Shimizu´s low temperature type color stars will give nice results. Some users have already mentioned that Hardt is also a good source for chlorate formulas. So are Ofca (Technique in Fire - Cut Stars) and Weingart, as well as Baechle - although his formulas often employ calomel and other more exotic stuff.

Edited by AdmiralDonSnider, 01 July 2009 - 03:33 PM.

[sir steve]

[quote name='50AE' date='22 May 2009 - 02:04 PM' timestamp='1242997482' post='56328']
This summer, I'm resuming my pyro activity and I'm nervous to find out the best chlorate compositions. I'm also nervous about safety, so I want safe compositions. But you may wonder why I want to use "chlorate" as oxidizer ?

The main reason it's - it's very cheap and easy to get ! I'm preparing it by the electrolysis of KCl solution. I recrystallize it two times and I obtain a good quality chlorate.
But as you know, it has incompatibilities ! No sulfur, no metal powders, and many others. As safety reference, I'd like to use Bill Ofca's article about chlorates.

I do not agree that copper oxide should not be mixed with KClO3. It is insoluable and I know of no reported problems.
Cu Bz can also be mixed with KClO3 but there is no point as the oxide is cheaper. CuBz can be used with KClO4 as a fuel
and catylist.

Steve

[sir steve]

!!!! Did you know that Barium chlorate is very unstable and has caused many accidents in history?! Green chlorate stars can and do spontaneously ignite! Not something I'd want hanging around in my house.

I don't find the warning very useful. what formula what circumstances? I could sayBarium Chlorate is the safest chemical used in fireworks. I agree you don't want themhanging around the house they are cat 1.1. Steve.

[seymour]

!!!! Did you know that Barium chlorate is very unstable and has caused many accidents in history?! Green chlorate stars can and do spontaneously ignite! Not something I'd want hanging around in my house.

I don't find the warning very useful. what formula what circumstances? I could sayBarium Chlorate is the safest chemical used in fireworks. I agree you don't want themhanging around the house they are cat 1.1. Steve.

What makes you think that?

The point has been made that chlorates, while fairly sensitive are excessively villianised. However I do not see how you consider Barium chlorate the safest of the firework chemicals.

[50AE]

What makes you think that barium chlorate mixtures will spontaneously ignite ?
I'll test how sensitive they are after I synthesize some Ba(ClO3)2 and I'll report the results here.
Finally I considered to not trust some warnings from Bill Ofca's, especially on the calcium sulfate, carbonate and copper oxide side. If he likes to warn us, why didn't he tell that dextrin sensitizes chlorates so much ?

Regards, 50AE