Chemite?

[MacTim]

Going through some old stuff that was rat holed away for years I came across something called "Chemite" not much info out there on the stuff so I thought I would as the Pros. 1. does it have a use in pyrotechnics? 2. How was it used? Throw this ole dog a bone...........

 

MacTim

[Crazy Swede]

Isnt that a brand name for detergents and similar industrial chemicals?

[davidh]

L-TR3: PETARDS Although simple in construction. Petards are extremely effective. The whole secret is in the composition, which is: Potassium Perchlorate 66 Aluminum, dark 34 (Parts by Weight) Chemite 1 

...

[davidh]

Looks like it's probably a fumed silica.

[MacTim]

davidh, Thank you for your input, I remember in my English class this phrase: "Hoist with his own petard", a phrase used in Shakespeare's Hamlet. The phrase's meaning is literally that a bomb maker is blown up. a petard is a small explosive device.

Yes it is quite "fluffy" not stuffy........... so in a FP formula you would add "a wee bit" to enhance the affects??

 

MacTim

[justvisiting]

Some tiny little voice in the back of my mind is associating the term 'chemite' with copper chromite, a catalyst. I didn't find any reference to it, but maybe chemite is a term for homemade copper chromite? Just a guess.

[Arthur]

Chemite.inc is or was a detergent supply company probably in NY state.

 

Unless it says more the manufacturer's name is as helpful as Heinz et,al.

[Mumbles]

Certain detergents and powdered soaps have been added to flash comps as well. I don't understand how it works, but it works. DavidH's suggestion of fumed silica is also very possible. Without a context or more details it will probably be hard to tell.

[Bourbon]

Snatched this from a book... I had read about Chemite "silicon dioxide" somewhere else but couldn't find it, so I picked this up instead from a different place. I was annoyed the first time I heard about chemite. I couldn't get anyone to tell me what it was. I was told repeatedly "those in the business know", as if it was some kind of a trade secret. I didn't find it for around 3 years when I stumbled across it... Disappointing to say the least. lol

CAB-O-SIL This concern with prevention of caking led to introduction of anti-caking agents, of which Cab-O-Sil was the main one, sold under the proprietary name "Salutex" by WesTech corporation and lately "Chemite" from Square Lake Enterprises. It is composed of silicon dioxide (sand) in particles on the order of a micron in diameter. The name "Salutex" apparently derived from the theory that it made for a bigger bang by keeping the particles of a flash mix separated on a microscopic level, thus exposing greater surface area for burning. 

[WSM]

Snatched this from a book... I had read about Chemite "silicon dioxide" somewhere else but couldn't find it, so I picked this up instead from a different place. I was annoyed the first time I heard about chemite. I couldn't get anyone to tell me what it was. I was told repeatedly "those in the business know", as if it was some kind of a trade secret. I didn't find it for around 3 years when I stumbled across it... Disappointing to say the least. lol

CAB-O-SIL This concern with prevention of caking led to introduction of anti-caking agents, of which Cab-O-Sil was the main one, sold under the proprietary name "Salutex" by WesTech corporation and lately "Chemite" from Square Lake Enterprises. It is composed of silicon dioxide (sand) in particles on the order of a micron in diameter. The name "Salutex" apparently derived from the theory that it made for a bigger bang by keeping the particles of a flash mix separated on a microscopic level, thus exposing greater surface area for burning.

 

Bourbon is right.

 

Chemite is another name for Cab-O-Sil or fumed silica. It served the purpose of "fluffing up" the flash powder so as to increase the flame propagation through the mixture (producing a faster burn and louder sound with less mass).

 

Us old dudes remember this stuff from the "Good old days".

 

WSM

[Arthur]

If the product the OP has is fumed silica it should be obvious simply because of the ultra low density of the product.

[dave321]

not sure how much you would use ?

 

but typically low %s improve the flow of powders significantly,

 

and if the flow improves this tends to pack down quicker,

so that might be a completely erroneous conclusion, re fluffing up.

 

fluffing up would be best performed by adding a % of coarse sawdust.?

[SharkWhisperer]

not sure how much you would use ?

 

but typically low %s improve the flow of powders significantly,

 

and if the flow improves this tends to pack down quicker,

so that might be a completely erroneous conclusion, re fluffing up.

 

fluffing up would be best performed by adding a % of coarse sawdust.?

A lot of Chicom KCLO₄ (and probably other chems) contain 0.5% or 1% Cabosil or similar to keep it free-flowing. Though perc isn't really hygroscopic, the finer powders especially tend to clump up into moderately hard slabs if left in storage for a long time. Cabosil just prevents this. I've used perc both with and without Cab, and I've never really been able to tell any obvious difference in behavior, in various colored stars, primes, and FP... Though I've never directly compared with and without. Most comps are pretty forgiving of your perc possibly being off by a very small fraction due to inclusion of a mostly inert adulterant.

[WSM]

Bourbon is right.

Chemite is another name for Cab-O-Sil or fumed silica. It served the purpose of "fluffing up" the flash powder so as to increase the flame propagation through the mixture (producing a faster burn and louder sound with less mass).

Us old dudes remember this stuff from the "Good old days".

WSM

 

 

Revisiting this subject, a few points come back to mind.

 

"Chemite" was a name attributed by a pyro supply seller (many years ago) to Cab-O-Sil, Aerosil or whatever other trade name for fumed silica you find. Fumed silica comes in two main types, hydrophilic and hydrophobic (water friendly or water hating, in simpler terms). The type we typically use is the hydrophobic type.

 

Fumed silica is used in many industries and for many different purposes. It can be a thickener or a free-flow agent, for example.

 

It's utility (and also possibly an added hazard in some cases) in loose metal-oxidizer compositions is due not so much as a free flow agent as it is for the extremely large surface area of this inert material. What this means is that it bulks up the loose metal-oxidizer compositions, allowing a lot of interstitial gaps, which allow the flame front to propagate faster through the powder, equaling a faster burning loose metal-oxidizer compositions (and possibly a more hazardous product).

 

For small items, this can be beneficial, but in large articles, it's an unnecessary risk and can result in disaster for the user.

 

Some pyrotechnists have opted for natural products to bulk up their loose metal-oxidizer compositions. Cat tail fluff (collected from the plant in water flooded areas) or puffed rice cereal have been mentioned in the past, as an additive for faster burning, loose metal-oxidizer compositions.

 

Another caution is a possible risk of silicosis due to unprotected exposure, if a HEPA filter is not used by the handler of much fumed silica.

 

I've been cautioned by knowledgeable friends, not to use fumed silica in potassium nitrate (as a free-flow agent) used in glitter mixes, as it tends to kill the formation of spritzles required for a proper glitter effect. I haven't seen this for myself but pass it on as a possible problem.

 

A possible source for Cab-O-Sil is from sellers of plastics materials, such as acrylic resins used for hobbies or boat and auto repairs, etc., since it is used as an inert filler/thickener for the liquid resins. It can come in a huge 10 Lb. bag (about 3 cubic feet in volume), which would last a very long time for a hobbyist.

 

Those are the thoughts that come to mind regarding fumed silica. More may come up later if I ponder the matter further.

 

WSM

Edited December 12, 2021 by WSM

[Bourbon]

Great info @WSM..

[WSM]

not sure how much you would use ?

but typically low %s improve the flow of powders significantly,

and if the flow improves this tends to pack down quicker,

so that might be a completely erroneous conclusion, re fluffing up.

fluffing up would be best performed by adding a % of coarse sawdust.?

 

 

One caution about adding sawdust to loose metal-oxidizer mixtures, is that all wood is not the same.

 

Some woods are more alkaline and others are more acidic in nature. Different components can react negatively to materials that change the pH of the mixture.

 

For example, some oxidizers break down in the presence of either strong acids or strong alkalis, generating unstable compounds and possibly leading to a runaway reaction (fire or boom!). Aluminum breaks down in even slightly alkali environments, and magnesium breaks down in even slightly acid environments. Magnalium might be a weak link between them, chemically speaking.

 

Speaking of magnalium, don't mistake it for an alloy, which would have a unique character from its components. Magnalium is actually an intermetallic mix, rather than a true alloy; and can suffer from any pH away from neutral (7.0). Realizing this, I believe you can mix powdered aluminum and magnesium to get a similar effect if you don't have access to magnalium (Re: Brock 1949, reference to the "Orion flashing guns" mixture, which might be one of the earliest "strobe" composition references in print).

 

Adding sawdust to a composition might create an unwanted hazard if the mixture isn't treated to slow or prevent such a reaction. Consider doing a pH test on your sawdust before considering its use, or deciding on a neutralizer or buffer to add.

 

WSM