Red star #2 Advice please

[Guest]

I have some strontium nitrate now, and I found this formula:

Red star#2 

Composition

20

Potassium chlorate

60

Strontium nitrate

20

Shellac

The directions are: Dissolve shellac in boiling ethanol, add the other ingredients and proceed as usual. The stars take unexpectedly long to dry. They can be dried in the sun or in a vacuum. Smaller stars dry faster.

I'm not sure about the proceed as usual part.

Would one try to make a dough consistency then screen cut or pump?

What about grinding the shellac flakes to the strontium and then just wetting the mix with alcohol, them pumping or cutting?

What about mixing it all dry, then make rolled stars only wetting with alcohol.

Or what about just adding the strontium to a bp star?

Anyways, I look forward to your replies.

[cmjlab]

Lots of questions!

Shellac dissolved in boiling ethanol (using a double boiler to avoid direct contact with heat source and ignition of alcohol), was the traditional way of adding it to a star comp.  Shellac typically takes longer to dry because it can form a skin and trap solvent in the star.

I have no idea if adding it dry with the star comp would work because I've never tried it or read about someone else doing it.  I'd imagine the main issue would be that adding ethanol to a dry comp with dry shellac would not result in very well bound stars since shellac is difficult to dissolve (hence the boiling alcohol).

Adding Strontium to a B.P. star may have 2 issues - one itay not burn enough for the Strontium Chloride emitters OR it will likely be overpowered by the B.P.'s yellowish flame.  That is pure speculation on my part, so I'd be curious to know your results if you try.  However, I believe that's why KCLO3 or KCLO4 are the oxidizers in addition to Strontium Nitrate, or it's Strontium as the oxidizer with lots of metal to increase the temperature.

[cmjlab]

I recently learned that adding a dry binder to star composition, then adding the solvent is a relatively modern concept.  In earlier times, they would dissolve the binder in the respective solvent then add it to  the mixed star composition as the last step.

I don't recall who to credit this info to, so it will have to suffice that someone else was discussing it and that's where I learned it from.

[AustralianPyromaniac]

I bind quite a lot of stuff with shellac, it's a great substitute for redgum or phenolic, with similar properties, and much easier to get for me. Everything dries very quickly, but I never use it above 5%. The resulting BP, stars, etc. are still porous enough to let the alcohol out, they also normally have other stuff in them, like charcoal, which helps. With a formula like that, at 20% shellac all dissolved, it's almost like trying to dry a block of plastic. KClO3 and strontium nitrate are likely to form strontium chlorate if dampened with water, which is super hygroscopic and the stars will never dry, this is why they have used alcohol with shellac as the binder. Any mix with these two compounds faces this issue. Strontium nitrate is hygroscopic, but the degree of this issue is overstated, the chloride contamination is what really makes it an issue, you'd have to know the purity of your sample to know this. 

Shellac does not activate in ethanol very quickly at all, at least the stuff I use. It really must be pre-dissolved. This is fine for cut or pumped stars but does not really work for rolled stars, at best you can dampen with alcohol with shellac dissolved in it, which works but not as well. For cut/ pumped stars, I dissolve the shellac in the minimal amount of alcohol possible over a few days, then add it in. Then I just keep adding more alcohol to get to the desired consistency for what I am doing.  

1) Try to find a different formula, the ones with insoluble salts of strontium (carbonate) can be dampened with water + dextrin. Or one with nitrate but with another primary fuel, and shellac as just a binder. 

2) Replace some of the shellac with a different fuel (high-quality sulphur, lactose, maybe charcoal) and just use the shellac as binder.

3) Use acetone or MEK, they are much more volatile and can find their way out of stars bound even with PVC as the binder, they should work better. 

4) Dissolve only 5% of the shellac in solvent, leave the rest powdered the formula. Stars will not be as strong but still strong enough?, it won't set nearly as solid.

Strontium in BP does work for red I believe, just not well. There is no chlorine, but the atom itself emits, requiring higher temperatures for excitation. Why would you want to go that route? In any case it will not work that well. 

Also why do you want to use a formula like this? The "rubber" stars are incredible, bound with acetone and parlon, would this not meet your demands better? Are you located in the US, or somewhere it is hard to get chemicals?  

Edited December 24, 2023 by AustralianPyromaniac

[cmjlab]

I would like to see a red star made from B.P. and Strontium nitrate.  I don't see how it's possible. I don't recall even seeing a red star with KNO3 in it.  

If I were a watering man, I'd bet you MAY get a pink. I've seen a few comps that use KNO3, some charcoal and some sulfur, but not in B.P. proportions.

But I'm willing to admit I'm wrong if someone can do it!  It would be interesting none the less.

[Guest]

Wow! Lots of great responses, thanks everyone!

If you've been following along, you already know this whole red thing started with some highway flares. They turned out to be useless probably because they were 30 years old or so, and none of the extraction methods seemed to work, so not knowing shit from shinola, I searched on pyrodata and found the red star#2 formula.

I was attracted to it because I already had shellac flakes, KCLO3 and alcohol, so I just ordered some strontium nitrate.

For certain reasons, I wasn't allowed to take chemistry in highschool, s added o I'm no chemist by any means, except what I've leaned by myself, online and here.

So today I took some of the SN ground it up, and added it to some MD, placed it in a trough, and lit it.  I used too much and it didn't work. I tried adding less, and got a decent red flame.

I then ground all the ingredients of the formula for red star #2 separately, mixed them and lit it, with nice results.

I went further and mixed some of my ground formula with MD and got a really hot red colored burning trough.

Next I took a whack at grinding some shellac into a fine powder and dissolved it into some boiling fuel grade alcohol. I then added the rest of the called for ingredients, stirred them in and evaporated it down to what acted and appeared a lot like R candy. I then smeared it onto a silicone honeycomb cell shaped hotpad, and placed it in a toaster oven at about 100-125 degrees or so until it solidified about 90%, removed it and let it finish cooling, evaporating, and hardening.

The results are what's in the video.

I tried launching them in some 3/4" inch shells, first mixed with 532, H3, and then 7.3. They didn't light.

Next, I primed them with NC and my mix of bp fines and 7.3, and still they didn't light using H3 and 532. So I'm guessing they need a hotter, easier burst, or an insane prime.

This is only day one, and a few hours into this experiment, but I believe I'll come up with something.

I've seen the rubber star kits on Sky Liar. I'm willing to try the method later, but not from them. In the meantime I'm sitting on 4 lbs of SN, and I'm going to get it to work!

So here's the video of the comp all by itself, no prime, and most likely not 100% dry. It's also a lot redder than it looks due to LED indoor lighting, and an iphone 7's response to things.

I have much more to add, but my hands are already asleep, and my brain needs to join them!

 

[Zumber]

I am witness who has seen potassium chlorate shellac and strontium nitrate based stars manufactured by our old persons (uncle grandfather) and I also prepared it for 10 years but now I dont since 2010.

The formula was used as a railway signal or flare (heard from grandfather)

Potassium chlorate 2 parts

Strontium nitrate 4 parts

Finely ground shellac powder (looks like turmeric) 1 part

Fine charcoal 0.1 part.

In this mixture What I have seen from grandpa and also I used to make same method and tried it lots of time too.....that they were grinding shellac flakes using coffee grinder and passing it through 150 mesh plus fine screen.

And sieve Chlorate strontium nitrate and shellac powder charcoal using 40 mesh screen.

And they damed that composition using hens egg(yellow yolk is not used)

As it is sticky and it was working too they used to make round stars.

I dont recommand this method I am just telling this what I have seen from ancestors just as a story.

It can be bound using 2 to 3 percent parlon and using acetone.

Shellac stars gives preety deep red colour but it burns too slower.

Edited December 24, 2023 by Zumber

[AustralianPyromaniac]

8 hours ago, cmjlab said:

I would like to see a red star made from B.P. and Strontium nitrate.  I don't see how it's possible. I don't recall even seeing a red star with KNO3 in it.  

If I were a watering man, I'd bet you MAY get a pink. I've seen a few comps that use KNO3, some charcoal and some sulfur, but not in B.P. proportions.

But I'm willing to admit I'm wrong if someone can do it!  It would be interesting none the less.

Ok maybe red is a push :)). But I think if you got strontium nitrate and kept mixing it with BP you'd eventually get a mix that burned more red than... yellow I guess... whatever colour BP is.  I more so meant starting with BP chemicals and strontium nitrate, you could do something with it. Without chlorine and with low flame temp, it would not be great. If that failed maybe ommit the charcoal and base it on mostly sulphur. I was not thinking of any published formula, just the general principle of the Sr emission, meaning I think it could be done to some extent, whereas the same idea with copper and barium salts lacking chlorine would not be possible. I have also read some people's work on KNO3 stars, and am vaguely remembering some of their formulas. 

6 hours ago, Bbqjoe said:

Wow! Lots of great responses, thanks everyone!

If you've been following along, you already know this whole red thing started with some highway flares. They turned out to be useless probably because they were 30 years old or so, and none of the extraction methods seemed to work, so not knowing shit from shinola, I searched on pyrodata and found the red star#2 formula.

I was attracted to it because I already had shellac flakes, KCLO3 and alcohol, so I just ordered some strontium nitrate.

For certain reasons, I wasn't allowed to take chemistry in highschool, s added o I'm no chemist by any means, except what I've leaned by myself, online and here.

So today I took some of the SN ground it up, and added it to some MD, placed it in a trough, and lit it.  I used too much and it didn't work. I tried adding less, and got a decent red flame.

I then ground all the ingredients of the formula for red star #2 separately, mixed them and lit it, with nice results.

I went further and mixed some of my ground formula with MD and got a really hot red colored burning trough.

Next I took a whack at grinding some shellac into a fine powder and dissolved it into some boiling fuel grade alcohol. I then added the rest of the called for ingredients, stirred them in and evaporated it down to what acted and appeared a lot like R candy. I then smeared it onto a silicone honeycomb cell shaped hotpad, and placed it in a toaster oven at about 100-125 degrees or so until it solidified about 90%, removed it and let it finish cooling, evaporating, and hardening.

The results are what's in the video.

I tried launching them in some 3/4" inch shells, first mixed with 532, H3, and then 7.3. They didn't light.

Next, I primed them with NC and my mix of bp fines and 7.3, and still they didn't light using H3 and 532. So I'm guessing they need a hotter, easier burst, or an insane prime.

This is only day one, and a few hours into this experiment, but I believe I'll come up with something.

I've seen the rubber star kits on Sky Liar. I'm willing to try the method later, but not from them. In the meantime I'm sitting on 4 lbs of SN, and I'm going to get it to work!

So here's the video of the comp all by itself, no prime, and most likely not 100% dry. It's also a lot redder than it looks due to LED indoor lighting, and an iphone 7's response to things.

I have much more to add, but my hands are already asleep, and my brain needs to join them!

 

Wow, you must have 12 fingers and then some more to lose making chlorate stars like that, hope it was a very small test batch. 100c? 100F? Crazy

The colour looks great. A burn-modifying fuel like charcoal 1-5% or sulphur 1-10% would improve ignitability or a hotter prime. Not sure I can recommend making that mix more flammable if you're treating it like that though. Better mixing of the oxidisers should also help. Oxidisers can be ball-milled together before mixing with shellac. Still, I think you should try a different formula. Do you only have KClO3 not O4? Do you make it yourself? 

 

[Guest]

6 hours ago, AustralianPyromaniac said:

Ok maybe red is a push :)). But I think if you got strontium nitrate and kept mixing it with BP you'd eventually get a mix that burned more red than... yellow I guess... whatever colour BP is.  I more so meant starting with BP chemicals and strontium nitrate, you could do something with it. Without chlorine and with low flame temp, it would not be great. If that failed maybe ommit the charcoal and base it on mostly sulphur. I was not thinking of any published formula, just the general principle of the Sr emission, meaning I think it could be done to some extent, whereas the same idea with copper and barium salts lacking chlorine would not be possible. I have also read some people's work on KNO3 stars, and am vaguely remembering some of their formulas. 

Wow, you must have 12 fingers and then some more to lose making chlorate stars like that, hope it was a very small test batch. 100c? 100F? Crazy

The colour looks great. A burn-modifying fuel like charcoal 1-5% or sulphur 1-10% would improve ignitability or a hotter prime. Not sure I can recommend making that mix more flammable if you're treating it like that though. Better mixing of the oxidisers should also help. Oxidisers can be ball-milled together before mixing with shellac. Still, I think you should try a different formula. Do you only have KClO3 not O4? Do you make it yourself? 

 

What are you going on about? The average day around here can be over 100ºF. I've seen 130º before. 

I seriously doubt much of anything I make will blow at those temps. But I could see where 100ºC could become as issue.

I dry my BP for a day in the 100º shade, and the next day I put it straight into the sun. Never had so much as a kernel spontaneously combust, although I think I've seen a few gingers burst into flames out here.😉🤣

I do have 04, I was just following the recipe.

TBH, I wasn't sure if the SN could be processed along with the chlorate. But if you believe 04 would work better, equally, or safer, I'm down with it.

The other thing is, I'm not throwing stuff in my gas oven in the kitchen, I have a little electric toaster oven outside for such things. I also have a wireless remote temp gauge to monitor things. I might not be jammed packed with knowledge or information, but I tend to believe I have more than my fair share of common sense, at least enough to still be alive in my 60's.

I've never mixed sulphur with kclo3 or o4, only because from what I've picked up so far, that's pretty much a recipe for a problem, but I might try a little charcoal first.

If you've got a better formula, I'm open to that as well. This is still the amateur forum right? I'm only here to learn.

Thanks for your input!👍 

Edited December 24, 2023 by Bbqjoe

[cmjlab]

There is a lot of stuff going onnon this thread!  🙂

Iso first to BBQ Joe and Australian Pyromaniac - I can admit when I'm wrong, and I was wrong.... I'm kind of surprised that adding SrN03 to B.P. resulted in red at all, I thought for sure that best case scenario, you add KCL03 contaminated SrN03 to B.P.and you may get orange since the chlorate can release some chlorine to help the color, but it sure looks like an ok red in the video, cool!

I still think that straight SrN03 would make orange at best, BUT that is just a wild guess and it clearly works better than I thought it ever would.

BBQJoe - the risk I think AustralianPyro was referring to was "grinding" up the Flare SrN03 which most agree includes KCL03 and Sulfur.  Grinding any KCLO3 when sulfur is present is certainly risky, as sulfur increases friction sensitivity, and lowers ignition temp (which also speaks to heating  up a mixture).  I'm glad it worked out for you, but he does have a point since even though you recrystallized the flare comp and potentially removed the sulfur and gained mostly Sr and KCL03 due to solubility, you added it to B.P. and re-wet the comp which adds sulfur back into the risk equation.

My *uneducated opinion* on the risk of KCL03/ sulfur combo (based on people's input who are far more experienced than me) - is that its often overstated because that is what they read in some pyro text, or heard someone else who has not much experience with it.  There's a lot of info in this forum, but basically the actual risk is that sulfur increases friction / heat / and possibly impact sensitivities, but will not spontaneous combustion of using modern sulfur that has minimal, or no, acidity (source of spontaneous combustion risk in combo with KCLO3 ).  If you are considerate of those risks, and focus on safe handling, as well as keep H20 away from it as much as possible, then the risk of spontaneous combustion is pretty minimal.  Again, just my 2¢, I use mostly KCLO3 comps and have not had an issue.  

Another little known risk with KCLO3 comps is that exposure to sunlight ha(i.e. drying chlorate stars in direct sunlight) has caused them to become much more friction and impact sensitive, and some possible reports of spontaneous combustion.  I don't know / understand the science behind it (displacement / UV rays? maybe) but I just don't dry chlorate in the sun.

I DO however, dry B.P. in the sun, in a dry box, or whatever is quickest to avoid having KN03 recrystallize and slow thenB.P. down.

 

[Arthur]

Please don't mix a BP formulation and chlorate. Chlorate and sulphur can produce very sensitive mixes that can fire spontaneously.

BP has a whole formulary of compatible mixes, Chlorate has it's own separate formulary of compatible mixes. 

[AustralianPyromaniac]

2 hours ago, Bbqjoe said:

What are you going on about? The average day around here can be over 100ºF. I've seen 130º before. 

I seriously doubt much of anything I make will blow at those temps. But I could see where 100ºC could become as issue.

I dry my BP for a day in the 100º shade, and the next day I put it straight into the sun. Never had so much as a kernel spontaneously combust, although I think I've seen a few gingers burst into flames out here.😉🤣

I do have 04, I was just following the recipe.

TBH, I wasn't sure if the SN could be processed along with the chlorate. But if you believe 04 would work better, equally, or safer, I'm down with it.

The other thing is, I'm not throwing stuff in my gas oven in the kitchen, I have a little electric toaster oven outside for such things. I also have a wireless remote temp gauge to monitor things. I might not be jammed packed with knowledge or information, but I tend to believe I have more than my fair share of common sense, at least enough to still be alive in my 60's.

I've never mixed sulphur with kclo3 or o4, only because from what I've picked up so far, that's pretty much a recipe for a problem, but I might try a little charcoal first.

If you've got a better formula, I'm open to that as well. This is still the amateur forum right? I'm only here to learn.

Thanks for your input!👍 

The part that worried me was the boiling down of the solution into R candy boiling off alcohol and heating a flammable composition using such an unpredictable source of heat. Not sure what the batch size was, I'd think quite small. As long as you understand the limits of what you're doing it's fine, I'd hope you wouldn't make a batch like that at 500g. Drying at 100 F is totally fine, just thought to check. Also, you Americans should really remember to put the F after your temps, not the whole world uses your archaic measurements . BP in the sun is totally fine, in chlorate stars the UV is an issue, not the heat - drying box is good. 

17 minutes ago, Arthur said:

Please don't mix a BP formulation and chlorate. Chlorate and sulphur can produce very sensitive mixes that can fire spontaneously.

BP has a whole formulary of compatible mixes, Chlorate has it's own separate formulary of compatible mixes. 

I do not understand why you'd say this. It really is not that bad! Sulphur chlorate is only a bit more sensitive than sulphur perchlorate. Acidic sulphur forms chloric acid which leads to spontaneous ignition when drying. Acid-free sulphur just does not have this issue. 

Sulphur compositions are more sensitive, and this is a different issue, but not sensitive to the point they cannot be handled safely. I'd like to challenge anyone to light a safety match without using the striker pad, it's not easy at all. Match heads contain both sulphur and chlorate, millions if not billions of those are handled safely every year.

I have made sulphur chlorate stars and stored them for extended periods of time without issue. Sensitivity-wise, I could never get them to light by friction, they cannot be ignited by light hammer blows, and even when struck hard they mostly do not light or only a small amount of the star lights. Shooting them in a slingshot into a brick wall reliably denotes them. The one shell I had fail to light hit the ground and that didn't light the stars either. 

I understand recommending beginners to avoid this hazard, but not by fear-mongering.

[Guest]

3 hours ago, cmjlab said:

There is a lot of stuff going onnon this thread!  🙂

Iso first to BBQ Joe and Australian Pyromaniac - I can admit when I'm wrong, and I was wrong.... I'm kind of surprised that adding SrN03 to B.P. resulted in red at all, I thought for sure that best case scenario, you add KCL03 contaminated SrN03 to B.P.and you may get orange since the chlorate can release some chlorine to help the color, but it sure looks like an ok red in the video, cool!

I still think that straight SrN03 would make orange at best, BUT that is just a wild guess and it clearly works better than I thought it ever would.

BBQJoe - the risk I think AustralianPyro was referring to was "grinding" up the Flare SrN03 which most agree includes KCL03 and Sulfur.  Grinding any KCLO3 when sulfur is present is certainly risky, as sulfur increases friction sensitivity, and lowers ignition temp (which also speaks to heating  up a mixture).  I'm glad it worked out for you, but he does have a point since even though you recrystallized the flare comp and potentially removed the sulfur and gained mostly Sr and KCL03 due to solubility, you added it to B.P. and re-wet the comp which adds sulfur back into the risk equation.

My *uneducated opinion* on the risk of KCL03/ sulfur combo (based on people's input who are far more experienced than me) - is that its often overstated because that is what they read in some pyro text, or heard someone else who has not much experience with it.  There's a lot of info in this forum, but basically the actual risk is that sulfur increases friction / heat / and possibly impact sensitivities, but will not spontaneous combustion of using modern sulfur that has minimal, or no, acidity (source of spontaneous combustion risk in combo with KCLO3 ).  If you are considerate of those risks, and focus on safe handling, as well as keep H20 away from it as much as possible, then the risk of spontaneous combustion is pretty minimal.  Again, just my 2¢, I use mostly KCLO3 comps and have not had an issue.  

Another little known risk with KCLO3 comps is that exposure to sunlight ha(i.e. drying chlorate stars in direct sunlight) has caused them to become much more friction and impact sensitive, and some possible reports of spontaneous combustion.  I don't know / understand the science behind it (displacement / UV rays? maybe) but I just don't dry chlorate in the sun.

I DO however, dry B.P. in the sun, in a dry box, or whatever is quickest to avoid having KN03 recrystallize and slow thenB.P. down.

 

I believe I may have mistyped or you misread. I believe I wrote that I mixed some strontium with bp and after two attempts, I did get some red, but what you saw burning in the video was the SN/kclo3/shellac formula.

You might have also missed the part where I said the flare extraction was a complete failure.

Anyways I didn't go further with my experiment today, too many other things to do, but will probably get back to it sometime next week.

Also to AP, I used a hot plate outdoors to heat the alcohol and shellac, then turned it down to the lowest setting and mixed in the kclo3 and strontium. When I considered close enough to done, I removed it from the heat and let the residual heat from the pan and stirring to get it down to a gooey consistency. After spreading it on the silicone pad, I let it sit for awhile, then put it in the toaster oven on low. 

Again, I'd like to thank everyone for their input and info!

[cmjlab]

My bad.  I thought you had made a B.P./ SrN03 red.