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Calcium Nitrate orange stars


PeteyPyro

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I found a 40 kg. pound bag of Calcium Nitrate (fertilizer grade) that was stored long ago. It was probably used by me years ago to treat calcium deficiencies in my soil in order to fix tomato 'end blossom rot' and cracking tomato fruit, and forgotten about. It was rather damp, but otherwise it seems fine. I dried out about a pound of it in my drying chamber, and tried a pinch in a torch flame. Classic Calcium bright orange flame color was observed. I realized that maybe I should put this 'free' resource to work in pyro, and was looking up orange star comp recipes. They seem to be using carbonate and sulfate salts of calcium, instead of the nitrate. Question (finally) : Does anybody know of a Calcium NITRATE star formula, or formulae, for orange stars that they like? Can this be easily substituted for Calcium Carbonate or Sulfate in stars/comets? At what ratio (1:1, 1:1.5 etc.) could this be used as a substitute? Is it too hygroscopic for consideration? Any thoughts or links would be appreciated, while it research the threads everywhere (I probably should have done this first in order to not be 'flamed' by y'all). Thanks.

 

ps. If anyone wants a pound or three (for free), for just the shipping costs, P.M. me.

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If you were not able to source a formula, there is a good reason for it: other have tried it but they failed miserably.

 

Calcium nitrate is far too hygroscopic to be of any use in pyro formulas.

Edited by a_bab
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"Calcium nitrate is far too hygroscopic to be of any use in pyro formulas."

Thanks, a_bab, I just did my homework, and I guess this is only good for my tomatoes. If I lived in the EU, I might be using my water softener's KCL for metathesis, to make KNO3. Thanks again. Back to other pyro. (I may still make a fountain for immediate use, before it clumps up or turns into into a puddle, like the CaCl does in my safe's DampRid.)

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Yup. One of my more memorable failures. I have a good brilliant red comp using strontium nitrate. Since calcium is in the same chemical family as strontium, I reasoned that I could just sub the Ca nitrate for the Sr. Worked, made a beautiful brilliant orange. (note: I live in the arid southeast part of Colorado at an elevation of ~6 800' ASL.) So, I pressed up a batch of stars using red gum and alcohol, and made a couple shells. Worked great.

Then the rains started, and with the increased humidity, the stars turned to mush!

One more reminder that it is essential to know the characteristics of any new chemical being introduced into a comp.

Bob

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Thanks, Bob. I just get curious when I see something that may be usefully repurposed in the art. I should have UTFSE first. It seems that certain carbonates are preferred, even over oxidizing nitrates, because of this.
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Well... If you went with a strontium nitrate composition, and substitute calcium nitrate, and then just sealed the darn thing with a airtight prime, or delay, you should be fine. So if you could "figure out" a worthwhile composition, and use a NC based prime or delay, it should be fine. Not sure it would be worthwhile, but possible.

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Well... If you went with a strontium nitrate composition, and substitute calcium nitrate, and then just sealed the darn thing with a airtight prime, or delay, you should be fine. So if you could "figure out" a worthwhile composition, and use a NC based prime or delay, it should be fine. Not sure it would be worthwhile, but possible.

I did. The comp in question contains 20% parlon, so it is quite amenable to 'screen-cutting' as in Ned Gorski's "rubber stars" article. The stars were quite acceptable, but I decided that they were not worth the effort as that method does not yield nice, regular stars for use as cores....

I had reasoned that adding red gum and binding with alcohol would make them (reasonably) moisture resistant. Nope.

Bob

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I'm tempted to try some Calcium 'orange'in a small round shell anyway. I do have a vacuum chamber that I can dry just about anything smaller than a loaf of bread, so I can get anything from stars to a pasted shell, very, very dry. Then I can seal it in a vacuum 'food saver' bag, with a desiccant pack, until I shoot it. I know the vacuum has removed all moisture when the vacuum holds steady. A lot of extra work drying stars and pasted shells, but I have time to burn. I'll post the video here in a few days, as we all like to SEE new stuff.
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Peter:

The comp I used was as follows:

Ca(NO3)2 50

MgAl (200-325 mesh) 30

Parlon 20

Binder 5

 

You can omit the binder if you choose to use the parlon with acetone as binder.

Bob

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Thanks, Bob. I'll try it, using acetone, as not much in this formula plays well with water.
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You are absolutely right. I should have specified "non-aqueous" binder. I suggest red gum/alcohol or phenolic resin/alcohol.

Bob

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Well... If you went with a strontium nitrate composition, and substitute calcium nitrate, and then just sealed the darn thing with a airtight prime, or delay, you should be fine. So if you could "figure out" a worthwhile composition, and use a NC based prime or delay, it should be fine. Not sure it would be worthwhile, but possible.

I fear that if your waterproof prime were truly so, it would also be flameproof. Pure NC lacquer will fireproof your stars. Add any charcoal to it, and it is no longer waterproof. Best idea is to not make such hygroscopic comps.

Bob

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Very true, Bob. At this point it's not feasible for 'normal' pyro, but just an exercise in 'proof of concept'. Nothing in the above formula works well with water, nor should it be bound with water based binders. If I didn't have a vacuum chamber for drying, and too much time on my hands, this would only be a 'thought experiment'. Calcium salts seem to be deliquescent anyway, like the chloride in my 'DampRid' tubs.
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I fear that if your waterproof prime were truly so, it would also be flameproof. Pure NC lacquer will fireproof your stars. Add any charcoal to it, and it is no longer waterproof.

 

Not really a problem. A step prime from the hygroscopic composition to a pure NC layer, and from there a step prime to a regular delay, or outer color / effect composition Is not exactly hard to make, would actually be airtight, and would ensure fire can pass from one composition to the next without issues.

I don't see it as a usefull method, but more then adequate for experimenting, and if you want to get rid of said nitrates...

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Thanks for the primer on primer recommendations, MrB. I was thinking along the same lines as you were. Yes, I'm trying to get rid of some of this extra CaNO3 in pyro, since I'm not growing tomatoes anymore. It's good for calcium deficient soils that needs a nitrate fix too. ✴I need a daily nitrate fix myself✴
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