Ned makes KNO3-glitter without Boric Acid, and seems to be very relaxed about it.

[WSM]

Also not a glitter.

 

AND tends to be somewhat treacherous, in my experience.

 

WSM

[WSM]

Also pretty expensive.

 

True.

 

Under other circumstances it can assist in the ignition of harder-to-light items, though (even though less expensive and less hazardous options exist).

 

WSM

Edited January 20, 2018 by WSM

[Ubehage]

Try this formula, ity doesn't require boric acid to be safe:

50% black CuO

50% Al

Bound with nc and primed with bp

It should be noted that CuO is a very energetic material. In the sense that it has a LOT of potential energy to be released under the right circumstances.

 

Copper in general, is not easy to "get going". It takes a relatively large amount of energy to ignite it.

On the other side of that coin, this also means that there is a huge amount of energy that CAN be released.

In my experiences, mixing CuO and Al can have disastrous consequences.

 

Be careful!

[pyrojig]

Just a little observation when I made glitters in past. Fine flake material has a lot of reactive surface area, while atomized or spherical doesnt. I believe on flake , even the coated bright flake heated up in nitrate mixtures . Now when using the atomized or sphere AL I noticed that there was little or no heating . Therefore I didnt use the boric acid in the mix. No ammonia smell either .

I dont believe that the boric acid inters the reaction of the glitters , but w/o seemed that the glitter was more pronounced.

 

Just a couple observations , not advise .

Also on the Cu/AL NC bound mixs, they can if intimately mixed , become quite energetic . .

[Seymour]

I've had Al-Nitrate react with Glitter mixes similar to D1 on multiple occasions, as well as having them not react most of the time.

None of the reactions were generating enough heat to ignite the spread out stars, but they often broke apart, and didn't work so well afterwards.

It helps to cut the water level down and dry them more with air flow than with heating. When I did get them starting to crack with the distinct sulfur based smell I simply made sure the stars were in the shade, away from things, and spread out on a tray (already were, but if not this is how they should be). Often they kept reacting, sometimes the shade stopped it. I let them be.

I hardly ever add Boric acid to Nitrate -Aluminium mixes, though there are cases where I would. Glitters, I rarely do and focus on drying conditions, somewhat like high charcoal stars.

Copper thermite can have significant value in many situations and i'll admit to a fondness of it. I'm not sure how it is too relevant in regards to the NO3- Al reaction potential though with or without Boric acid.

I've made batches with quite fine CuO and Indian Dark flake Al which while not as good as KClO4 with that Al, did serious damage in small quantities barely confined. Piles go boom.

It can be used to boost shells as flash powder for those without KClO4.

With fine glitter Al it burns really nice in long lines. so fast. Nice trail of pink or red Cu left behind.

 

Edited January 26, 2018 by Seymour

[Seymour]

As for the ignition of CuO/Al, depends on the Al (CuO too, but not usually so significant. Finer = faster, purity and all that). With fine flake it'll go off from black match and visco.

With larger atomised it will not light from a stick of black match, however any primed KClO4 based colour star with MgAl is in my experience an extremely reliable and easy igniter for CuO/Al using coarser atomised Al.

Scraps and deformed stars, you get the idea.

[pyrojig]

To chime in, i believe you hit the nail on the head with the water being a minimal and the drying arrangement being a factor . Fast drying or sun can cause a reaction , but you dont want stars to sit wet for long periods either ( weeks) . water content is a huge factor in glitters and their performance . 7% seems to be a standard even less at times . (water content)

Also forgot to mention how the stars are made..... is a huge factor too. a sheet of cut stars close together is a larger chance to heat up ....lots of surface area. pumped and pressed stars are great, followed by rolled . these rarely heat up

Edited January 26, 2018 by pyrojig