28 replies to this topic

[Karl Mitchell-Shead]

A friend showed me this clip and asked for my thoughts....



Now im not going to say a word, i know my thoughts, i also know what application Pentaerythritol has in PETN, however my chemsistry horizons are somewhat limited when it comes to exotic compounds, can anybody see any profound or negative effects PE would have on this composition because i can't!

Cheers in advance

[Karl Mitchell-Shead]

Oh and i'm not really into the practical side of things anymore so we can skip past the 'dabbling' warnings.

[Arthur Brown]

Why do youtubers always want to make the best/worst/kewlest Flashpowder!
1 I see no chemical advantage over conventional flash
2 It's a waste of good organic intermediates that have better uses.

Interesting also that the popup ads from google were a UK EOD company and printer cartridges!

[BrightStar]

Yup, this seems fairly pointless to me. It's just adding an expensive and not particularly effective ingredient to the mix.

One interesting exotic flash-like mix is the HMTD and Dark Pyro Al used as the comp to dust the inside of shock tube. I don't know whether any additional oxidiser is used, so it's probably not a binary flash mix in the traditional sense.

Given that we try not not to discuss HE on this site however, I'll leave it there...

[Potassium chlorate]

If you want an extremely powerful flash powder, simply substitute KClO₃ for KClO₄ in the standard 70:30 with Dark Pyro Al. The flash will be tremendous. It will also be more dangerous, of course.

As mentioned before this is just a waste of pentaerythritol.

[Mumbles]

I'd honestly be surprised if that guy even got PE. You can make a FAR more powerful, and vaguely safer mix with:

70 - Perc
20 - Benzoate
10 - Aluminum

I've been using it more often for larger salutes to save a bit of money. Even in bulk, blackhead aluminum is still $9 a pound. I bet I could replace it with cheaper bright flake.

[MDH]

Or you could just use bulk potassium sorbate like I suggested a million times. Perhaps it's just me, but bright flake aluminum needs far too much confinement to do its job.

The Chinese have used potassium terephthalate as an intermediate in flash powder mixtures which makes it burn somewhat like a flare outside containment, but explosively inside containment.

[Karl Mitchell-Shead]

Glad to see my thoughts are echoed on the use of PE

[pyrotechnist]

Or cheaper yet stop using perc and use a readily available oxidizer like calcium sulphate for flash with MgAl or even copper oxide with aluminium or MgAl confined makes a nice deep boom. Though it may require a thermite mix on the end of your fuse to light it.

[Mumbles]

Copper oxide is at least 2-3 as expensive as perc here. The same goes with potassium sorbate, not cost effective, even for a VERY slight gain in total energy output (less than 3%). It's no less than 4x as expensive.

By larger salutes, I meant bottom shots. Plenty of confiment for bright flake, or even atomized to do the trick.

The so called "negative explosives" definitely have merit. I just haven't gotten around to experimenting with them. It's a bit daunting to be working with large salutes, and not know if they'll even go off.

[dr thrust]

sorry to go off topic, but ive never seen/heard of potassium sorbate as a fuel before, would it be suitable as a fuel in a rocket propellant?

[MDH]

Copper oxide is at least 2-3 as expensive as perc here. The same goes with potassium sorbate, not cost effective, even for a VERY slight gain in total energy output (less than 3%). It's no less than 4x as expensive.

By larger salutes, I meant bottom shots. Plenty of confiment for bright flake, or even atomized to do the trick.

The so called "negative explosives" definitely have merit. I just haven't gotten around to experimenting with them. It's a bit daunting to be working with large salutes, and not know if they'll even go off.

On the sorbate - Yes, it's expensive unless you buy it in bulk quantities. And it is actually surprisingly fast burning. I have used tiny amounts to produce quite powerful crackers, and it can be used as a booster.

I don't think it can be used as a rocket fuel - it would probably explode. Perhaps with potassium nitrate and sulfur, but definitely not with chlorates or perchlorates.

Edited by MDH, 14 April 2010 - 09:50 PM.

[digger]

Hey I can supply the potassium sorbate at prices far lower than perc! I have 250kg in stock at the moment looking for a home.

It can now be had cheaper than the benzoates! (I will even be offering a special on these soon as I will be getting a big delivery in the next week or two)

[digger]

P.S. I think the sorbate would make a good rocket fuel. My results suggest it is of a similar power to salicylate whistle.

I will give it a go in a couple of weeks time to see how it performs.

D

[dr thrust]

ill look forward to that!