Strobe Rocket Fuels

[californiapyro]

Making strobe rockets, really fascinating things. problem is, I really don't want to use dichromates, seeing as there are many hazards involved with them. I was wondering if there are fuels without them, and if so how that affects performance.

[Mumbles]

I don't think you're going to be able to get away from dichromates entirely. The metal is often treated with dichromate, and then additional dichromate is added to the composition as kind of a "buffer", and a catalyst. I've never seen a very good looking rocket that doesn't use ammonium perchlorate based compositions, which really require the usage of dichromate. The nitrate based strobes burn pretty slow and are not nearly consistent enough.

 

Really the only hazards with dichromates are don't get them in your system. Pretty much the same hazards for barium salts, antimony trisulfide, or a variety of other pyro chemicals. Respirator and proper gloves and you're good to go.

[californiapyro]

okay, thank you. I believe I will be using this formula then:

 

am perc 57

mgal 24

baso4 14

k dichromate 5

mineral oil 2

 

So should I treat the mgal with the dichromate first, and if so how? and how fine does it need to be? sorry for all the questions, I just want to be as safe as possible with these.

[allrocketspsl]

Blue strobe rocket propellant

Source: Greg Gallacci <psygreg@u.washington.edu

Comments: The GE silicone II is noted for having an ammonia-like odor, where the GE silicones smell more like vinegar. The dimensions of the rocket made with this propellant were 1 1/8 inch ID, with a 1/2 inch core.

Preparation: Mix the copper oxide, PVC and silicone first, in a plastic bag. Then mix in the ammonium perchlorate. The stuff is said to be somewhat crumbly, and presses well.

 

Ammonium perchlorate..............................63

Silicone II.......................................22

Copper(II)oxide...................................10

PVC...............................................5

 

 

 

 

heres an easy one

 

 

 

[californiapyro]

oh, thanks

[Mumbles]

Good luck with that particular blue formula. I know many who have tried and failed to make one that actually strobes. It seems quite dependent on the silicone used. It makes a decent blue star and bluish rocket propellant though. It's also somewhat advisable to let it partly cure before trying to press it.

 

So, that white strobe formula you posted came from Skylighter in a Ned Gorski article, where it specifies -200 mesh. I'm not sure where exactly you got it, but it's always good to have the original source. I also have similar formulas that call for a variety of meshes of MgAl and Mg. This is where you really have to tweak it yourself to get where you desire. I've never heard of people needing to pre-treat MgAl with dichromate solution the same way that is required with straight magnesium. In that formula, I suspect the dichromate is of a ball milled variety. I'm not sure if you were asking about the dichromate or the MgAl, but I figured I'd answer both.

 

Some do not like the color of the straight BaSO4 white strobes, as it does have a distinct greenish tinge if using good pure chemicals and done properly. One of the tricks is to replace 2 or 3 parts of the barium sulfate with strontium sulfate, which seems wash it out to a clean white.

[californiapyro]

yeah I tried that blue, and when wet it "puffs" a little bit for me. I'll see how it turns out. Yes, I got it from the sl article, and the mgal i have is -200. okay, so I would need to mill my dichromate before use. yeah I have noticed that green in some strobe stars I did before, I think i'll use your trick. when you say it makes a decent rocket propellant, would that be nozzleless, cored, what? Thanks for being so helpful!