Guest PyroManiac1 Posted January 5, 2020 Posted January 5, 2020 There are a few flare recipes on Pyro Data that I have all other ingredients for but "Calomel". I learned that this is a very toxic and hard to get mineral formerly used in insecticides. Is there anything I can substitute the calomel for in this recipe https://pyrodata.com/compositions/Purple-torch-1 This ingredient doesn't seem very widely used so I have no idea how it contributes to the composition.
Arthur Posted January 5, 2020 Posted January 5, 2020 (edited) Well it's the only chlorine donor in that formula, so try subbing it with your favourite chlorine donor, PVC Parlon etc. Just also beware of burn rate changes. Edited January 5, 2020 by Arthur 1
NeighborJ Posted January 20, 2020 Posted January 20, 2020 (edited) Does HCB have much fuel value? Edited January 20, 2020 by NeighborJ
Guest PyroManiac1 Posted January 20, 2020 Posted January 20, 2020 Yes. I did try this out. I substituted the calomel with Parlon. It wasn't very impressing to say the least. You could see a little bit of blue/purple near the nozzle but other than that it was pretty disappointing. There isn't any control so I don't know if the recipe just isn't good or it was because of the Parlon substition. I substituted it 1:1 Parlon to Calomel.
Arthur Posted January 20, 2020 Posted January 20, 2020 The problem with older comps is that some use lead mercury or arsenic compounds all of which are needed for correct function but not wanted in formulae now that their toxicity is better known.
Arthur Posted January 20, 2020 Posted January 20, 2020 I must say that I'd prefer to work on the veline system of colours and use the purple mix using red yellow and blue. I'd be very keen to avoid the use of heavy metals.
davidh Posted January 21, 2020 Posted January 21, 2020 In all honesty, if you're looking at formulas with Calomel, you should probably already know all of your substitution options. Just saying.
Guest PyroManiac1 Posted January 21, 2020 Posted January 21, 2020 In all honesty, if you're looking at formulas with Calomel, you should probably already know all of your substitution options. Just saying.What is that supposed to mean?
davidh Posted January 21, 2020 Posted January 21, 2020 The antique formulas can be very dangerous. I would highly recommend steering clear of them until you understand more of the chemistry. The bad thing about informal collections of formulas is that it is difficult to tell the dangerous ones from the safer ones. Lancaster 3rd rev has several colored fire formulas on pages 221-222. That would be a better place to start. Later, after you have more understanding how the many different chlorine donors affect fuel ratios, burn rates, and color production, you will be in a better position to safely use those antique formulas. That's just my two cents (from someone that has had bad formulas heat up on him...).
Arthur Posted January 21, 2020 Posted January 21, 2020 There are historic formulae with Realgar, Orpiment, Paris Green, Lead Nitrate, and Calomel. They were important to the development of the history of fireworks BUT really have no purpose now. They are hazardous to work with and spray toxic chemicals over the firing site, so I'd prefer never to have to use these chemicals again. There are so many lists of star formulae, lance formulae and torch and flare compounds that can now be found that some of the old formulae can e relegated to history. Now if anyone can explain why lead nitrate is better for making slow match than potassium nitrate, then I'd like to hear please.
NeighborJ Posted January 22, 2020 Posted January 22, 2020 (edited) Lead nitrate prohibits the formation of larger nitrate crystals as it dries. Im certain there are other reasons but by controlling the particle size in this manner would make more consistent fuse burn rates. I've not had any experience with it's use so I can only draw this info from the scattered tidbits I've read. As far as scattering toxic chems across the shoot site much of that statement is misleading. Yes those heavy metals do end up in the environment. After they are burnt they end up as rather inert nonsoluble compounds which are no more toxic than everything else we are exposed to. The problem happens when inexperienced pyros use those chems and end up with blown blind stars. This would definitely spread a few toxins. Edited January 22, 2020 by NeighborJ
Boophoenix Posted January 24, 2020 Posted January 24, 2020 Not a quote, but Mike swisher once said something along the lines of Calomel is a unique chlorine donor for it’s low chlorine value. It can increase the flame envelope size, but doesn’t really adversely effect a formula by adding more. Me: If I’m not mistaken it’s used in fairly high ratios in many formulas that shows signs of this being true. PyroM, in my own little tinkerings with other things I find chlorine donors to emit a fair amount of yellow excess carbon like properties when in excess. Your 1:1 was very likely a very poor test as calomel has a very low chlorine value in comparison to parlon. Not to mention our current standard chlorine donors do normally have effects of formulas. You might try something like one fifth the amount of parlon or less and see what happens. Yes, 1/5 is less chlorine than the Calomel than the near 1/4 math gives, but the little extra may be less impact on the formula. Fair information I’m just grasping at ideas I don’t know Jack about the chemistry of it I’ve just followed threads on Calomel for a while as they are interesting to me. https://www.skylighter.com/blogs/fireworks-information/chlorine-donor-chemicals For some reason fire suppression rings in my mind when talking about chlorine donors. It might just be a strange association I have or there may have been mention at some point over the years. I don’t recall why I have this association. I kind of suck at retaining things I’ve read.
Mumbles Posted February 15, 2020 Posted February 15, 2020 I was just thinking the same think BooPhoenix. Calomel is about 15wt% chlorine. Parlon is about 70 wt%. It's not always as simple as a simple replacement of course. At 10% of the total comp, I don't think it's unreasonable though. A 1:1 sub should be giving more than sufficient chlorine. The main issue I'd expect is flame temperature. Calomel supposedly gives up it's chlorine at a pretty low temp. The mix of sulfur and perchlorate should also generate some chlorine in its own. Some more traditional organic fuels like red gum, shellac, phenolic resin, colophony, etc. Might help. Copper powder, if available is another idea. I included a formula from Skylighter, via rec.pyro, for potential inspiration. Rolled Blue Fireworks Stars From rec.pyro (in part)Potassium perchlorate 36Sulfur 3Red Gum 3Shellac 8Copper 6Parlon 4
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