Comps including Parlon and Dextrin

[stix]

I've been doing some research on this forum and elsewhere and still don't have a satisfactory answer that makes sense.

 

Some compositions include Parlon and Dextrin. This is the composition in question, I'm not sure where I got it from so I cannot give due reference to the author.

 

GREEN STAR

56 Barium Nitrate

17 Magnalium

17 Parlon

7 Red gum

5 Dextrin

 

From what I've gathered, Parlon is mainly used as a chlorine donor, but also a binder. Also, I thought Redgum was primarily used as a binder, but read that it's main use is a fuel... then why is the Dextrin required? ... as the main binder?... Confusing.

 

I have all the ingredients for this comp except for the redgum which I'll have in a few days.

 

So, I was looking through my database at possible comps to make (without KClO4) and came across this green star formula. The the first question I asked myself was "What solvent do I use"? First I thought Acetone, but then I saw Dextrin, so now I'm thinking water, otherwise what purpose does it serve?

 

I've read this from http://pyrodata.com/definitions/Binder

It has useful information but of course it doesn't give any explanations of the purpose of ingredients in a particular composition, and how could it anyway.

 

I still think acetone is the correct solvent. Although after re-reading my post for errors, I'm sure I claimed that it must be water???

 

Cheers.

[PIL]

Both acetone and water will work,it's just a matter of which binder will be activated.

Actually you can try creating your own formulas. Due to extremely hot-burning magnalium ,the choice of binder becomes less important .If you add enough oxidizer, vibrant red and green metallic stars will be very easy to make .

Edited August 30, 2015 by PIL

[nater]

In that formula, the red gum serves as a secondary fuel to the MgAl. The Parlon is the chlorine donor. Normally when an author includes dextrin, it is intended to be the binder with water as the solvent.

 

Troy Fish wrote an article promoting the use of parlon bound stars to make then waterproof. He researched a variety of solvents to dissolve the parlon and use it both as a chlorine donor and binder. Acetone was not the best solvent to make waterproof stars, but it is easily available and dries very quick. Gary Smith took inspiration from this and further developed his system for screen sliced, parlon stars which was again refined and publicised by Ned.

 

Many of the comps listed in Gary Smith and Ned's articles were modified from widely used compsm . This is one reason why you find different information about binders and solvents used with essentially the same composition.

 

As printed, the solvent would be water. There is no reason why you could not use acetone to activate the parlon. It should be mentioned that there is a slight fuel Value to dextrin as well. You could omit the dextrin entirely without ill effect assuming you activate the parlon as a binder. You could also omit the dextrin and increase the red gum slightly to compensate, but it would not be a 1:1 replacement.

[stix]

Thanks PIL,

 

At this point I won't be creating my own formulas. Sugar rocket fuel, yes, and some basic charcoal stars, yes and some very nice glitters, all good.

 

These are the things that I've been confident enough to make with great success. Coloured stars is a new game. Choice of binder in this situation is not obvious.

[stix]

. . . As printed, the solvent would be water. There is no reason why you could not use acetone to activate the parlon. It should be mentioned that there is a slight fuel Value to dextrin as well. You could omit the dextrin entirely without ill effect assuming you activate the parlon as a binder. You could also omit the dextrin and increase the red gum slightly to compensate, but it would not be a 1:1 replacement.

 

Thanks Nates - the way you have described it actually makes sense.

 

Without any great knowledge and very limited experience in these type of comps, for some reason it annoys me that the dextrin is there in the first place. Any acetone bound star has the appeal of immediacy - whereas charcoal comps plus water take 7+ days to dry properly.

 

I think I'll be going this way: dropping the dextrin, upping the redgum a bees dick or two, and using acetone as the solvent.

 

Reasonable?

[pyrokid]

Dextrin has the advantage of being very cheap. Additionally, some people have problems with perceived negative effects of parlon on star color. It other words, parlon can cause unattractive tails and slightly spoil the color.

 

I prefer to use water as a solvent, to avoid the headaches associated with acetone.

[rogeryermaw]

Headaches literal or figurative? If acetone vapors are giving you a headache you need ventilation. Vapors from acetone creep the floor looking for an ignition source and build up fast. The figurative headaches such as the stringy sticky mess aren't so tough to handle.

[stix]

Headaches literal or figurative? If acetone vapors are giving you a headache you need ventilation. Vapors from acetone creep the floor looking for an ignition source and build up fast. The figurative headaches such as the stringy sticky mess aren't so tough to handle.

 

Haaaaaaa... chuckle..... that's pretty good Roger, very funny. Usually for test comps I would make around 50 grams, so hopefully lack of ventilation won't be the thing that gives me the first headache!

 

I never really thought about the acetone vapours "creeping the floor looking for a source of ignition" something to be careful about and keep in mind.

 

I probably should try both methods, ie. an actetone comp, then a water dissolved version, and see which one produces the best green colour.

 

Cheers.

[Andres1511]

I would go for the dextrin and water. Where stars with a high charcoal content might take 7+ days to dry, colored stars with water take much less time. From small (5mm cubes) to big (12mm, half of an inch cubes) it takes approximatly 1-4 days to dry, if you don't overwet. Good pumped stars might even take less time, but they take more time to make. Parlon bound stars might also create an orange glowing "skeleton" afer the star burns out. You might see this in the air, and it's like a really ugly color change. I've had this with a green comp very similar to yours.

 

EDIT: when I say water, I mean water with some alcohol

Edited August 31, 2015 by Andres1511

[Arthur]

Given the choice as in the formula that you quote, I'd use water for price or acetone for speed. An Acetone solvated star will dry in an hour or so, a water moistened star will take a week or more.

[stix]

Thanks everyone for all the info, I've learned a lot.

 

The overall consensus is that water is the intended solvent for this comp. So that's what I'll do first, but I'll also make an acetone version as well.

 

I'll be making 3/4" pumped comets and shooting from a star gun - which is my preferred (and only) method at this stage - I do like the "up close and personal" experience of seeing the star/comet shoot upward leaving a nice fat tail - satisfying enough for me at this point.

 

The funny thing is, is that green is not my most liked colour for stars - that formula is the only one I had using ingredients at hand except for redgum (coming soon). Red could be done, I have Strontium Nitrate, but not sure if a direct substitution is correct. My favourite colour, as for many others is blue. I've already resigned myself to the fact that without KClO4 it's not going to be doable.

 

Anyway, what I'm aiming to do is make a matrix star with a base colour to augment and contrast with some glitters that I've already made (Gold Twinkler) then perhaps at the head, include some dragons eggs (in hand) for a sort of finale. All this in a 3/4" comet?

 

The appeal with the parlon and acetone is that in my mind, I could make a plastic play-dough type putty composition, that could easily be embedded with small cubes of various comps, then shaped to suit an outcome, in a mechanical but ultimately artistic sense.

 

Naivety?... Most likely... but at least it keeps me learning.

 

Cheers.

[rogeryermaw]

 

Haaaaaaa... chuckle..... that's pretty good Roger, very funny. Usually for test comps I would make around 50 grams, so hopefully lack of ventilation won't be the thing that gives me the first headache!

 

I never really thought about the acetone vapours "creeping the floor looking for a source of ignition" something to be careful about and keep in mind.

 

I probably should try both methods, ie. an actetone comp, then a water dissolved version, and see which one produces the best green colour.

 

Cheers.

chemically they should be the same. i would think the only difference would be that, by dissolving the parlon, that particular chemical is far more intimately mixed and may increase burn speed since parlon, however poor, does have some fuel value....but i have doubts that it would be noticeable,

 

check out the red and green shells i uploaded a few days ago in my experiments thread. the green left no glowing mess and it was parlon/acetone bound.

 

strontium is not as heavy as barium so the sub isn't exactly 1:1 but its close. just a few percent increase in strontium will do fine.

 

don't give up on blue just yet. you don't necessarily need perc, chlorate or a.p. if your fuel choice burns cool enough and your oxidizer burns color neutral. i'm trying out a few comps with more commonly available oxidizers...probably nothing that has never been done but if i can yield a decent result i'll pass it on.

Edited September 3, 2015 by rogeryermaw

[PIL]

chemically they should be the same. i would think the only difference would be that, by dissolving the parlon, that particular chemical is far more intimately mixed and may increase burn speed since parlon, however poor, does have some fuel value....but i have doubts that it would be noticeable,

 

check out the red and green shells i uploaded a few days ago in my experiments thread. the green left no glowing mess and it was parlon/acetone bound.

 

strontium is not as heavy as barium so the sub isn't exactly 1:1 but its close. just a few percent increase in strontium will do fine.

 

don't give up on blue just yet. you don't necessarily need perc, chlorate or a.p. if your fuel choice burns cool enough and your oxidizer burns color neutral. i'm trying out a few comps with more commonly available oxidizers...probably nothing that has never been done but if i can yield a decent result i'll pass it on.

The molar mass of anhydrous strontium nitrate is 212g/mol. The molar mass of barium nitrate

is 261g/mol. Since they are both alkaline earth metal, they decompose in the same manner. So you can substitute 0.82 gram of Sr(NO3)2 for every gram of Ba(NO3)2.

Blue is a tricky color.Nitrates burn too cool to release the copper from copper oxide.Fuel that burns with perchlorates as oxidizer often smoulder with nitrates.

[stix]

. . . check out the red and green shells i uploaded a few days ago in my experiments thread. the green left no glowing mess and it was parlon/acetone bound . . .

 

Just did - and very nice indeed Roger. Nice enough that it's made me want to change tack - I may as well go for Red using this Skylighter formula:

 

RED STAR

53 Strontium Nitrate

19 Magnalium

17 Parlon

11 Red gum

+ 22% Acetone

 

The molar mass of anhydrous strontium nitrate is 212g/mol. The molar mass of barium nitrate

is 261g/mol. Since they are both alkaline earth metal, they decompose in the same manner. So you can substitute 0.82 gram of Sr(NO3)2 for every gram of Ba(NO3)2.

Blue is a tricky color.Nitrates burn too cool to release the copper from copper oxide.Fuel that burns with perchlorates as oxidizer often smoulder with nitrates.

 

Thanks PIL, I've copied that down for future reference. Since now I'll be starting with Red, that would convert to multiplying the Sr(NO3)2 by 1.2 for the correct amount of Ba(NO3)2. If my math is correct.

 

Would priming these stars with the "Black Powder Parlon-Star Prime" which is on the same skylighter page

http://www.skylighter.com/fireworks/how-to-make/red-rubber-stars.asp

be good enough - or will it require a hotter prime?

 

[EDIT]

 

Yeah, I guess I'm taking my own thread off-topic.

 

So to summarise, what I've learned is:

The intended binder for the original formula is dextrin dissolved with water. With some experimentation (which has already been proven), the dextrin could be eliminated and acetone used to dissolve the parlon as the binder - which would give quicker setup times, but possibly not as clean burning stars - which didn't seem the case with the stars Roger pointed out in his experiments thread.

 

Cheers.

 

Well, I may as well go the whole nine yards and compare the two:

 

GREEN STAR RED STAR

56 Barium Nitrate 53 Strontium Nitrate

17 Magnalium 19 Magnalium

17 Parlon 17 Parlon

7 Red gum 11 Red gum

5 Dextrin -

 

+ ??% Water + 22% Acetone

 

As per my above calculation: 53 x 1.2 = 63.6. So I guess that's not entirely correct, but who cares if the formula produces a good result?

Edited September 4, 2015 by stix

[mabuse00]

The math is not super critical. With 56% Ba-Nitrate you should do fine.

 

 

Would priming these stars with the "Black Powder Parlon-Star Prime" which is on the same skylighter page

http://www.skylighte...ubber-stars.asp

be good enough - or will it require a hotter prime?

 

If your priming layer is thick enough and your stars wont be ejected from the shell at to high speeds you might get away with the "Black Powder Parlon-Star Prime".

 

I would prefer to give them a thin layer of perchlorate hotprime first, like the one mentioned in the article, or something similar, like Monocapa ect.

 

If you want to save/dont have perchlorate, you can also try to use a 50/50 mixture of the

Black Powder Parlon-Star Prime and your star composition as the inner priming layer.

 

 

[rogeryermaw]

Stix if you can get smokeless powder that's the way to go. I have a purposed spray bottle for priming with n.c. in acetone very thin. As with cut stars, dust both sides of your patty before cutting with mill dust, cut and dry completely (3-4 hours). Then I lay them out on wax paper and spray with the n.c. after which I dump the sheet into my priming box and toss. This prime consists of mill dust with about 8% mgal (80-200). They light pretty reliably.

[PIL]

 

Just did - and very nice indeed Roger. Nice enough that it's made me want to change tack - I may as well go for Red using this Skylighter formula:

 

RED STAR

53 Strontium Nitrate

19 Magnalium

17 Parlon

11 Red gum

+ 22% Acetone

 

 

Thanks PIL, I've copied that down for future reference. Since now I'll be starting with Red, that would convert to multiplying the Sr(NO3)2 by 1.2 for the correct amount of Ba(NO3)2. If my math is correct.

 

Would priming these stars with the "Black Powder Parlon-Star Prime" which is on the same skylighter page

http://www.skylighter.com/fireworks/how-to-make/red-rubber-stars.asp

be good enough - or will it require a hotter prime?

 

[EDIT]

 

Yeah, I guess I'm taking my own thread off-topic.

 

So to summarise, what I've learned is:

The intended binder for the original formula is dextrin dissolved with water. With some experimentation (which has already been proven), the dextrin could be eliminated and acetone used to dissolve the parlon as the binder - which would give quicker setup times, but possibly not as clean burning stars - which didn't seem the case with the stars Roger pointed out in his experiments thread.

 

Cheers.

 

Well, I may as well go the whole nine yards and compare the two:

 

GREEN STAR RED STAR

56 Barium Nitrate 53 Strontium Nitrate

17 Magnalium 19 Magnalium

17 Parlon 17 Parlon

7 Red gum 11 Red gum

5 Dextrin -

 

+ ??% Water + 22% Acetone

 

As per my above calculation: 53 x 1.2 = 63.6. So I guess that's not entirely correct, but who cares if the formula produces a good result?

There's 3 percent decrease in the oxidizer ,but 3 percent increase in the fuel. And your red star formula burns more resin fuel which consumes way more oxygen than dextrin .

Stars burn in the air ,so atmospheric oxygen should be taken into consideration. Most of the star comp is oxygen-deficient.An over-oxidized star will create a big piece of slag.

[stix]

The math is not super critical. With 56% Ba-Nitrate you should do fine.

 

 

If your priming layer is thick enough and your stars wont be ejected from the shell at to high speeds you might get away with the "Black Powder Parlon-Star Prime".

 

I would prefer to give them a thin layer of perchlorate hotprime first, like the one mentioned in the article, or something similar, like Monocapa ect.

 

If you want to save/dont have perchlorate, you can also try to use a 50/50 mixture of the

Black Powder Parlon-Star Prime and your star composition as the inner priming layer.

 

 

 

Thanks mabs. Nah, Unfortunately I don't have perchlorate. But your suggestion of a "50/50 mixture of the Black Powder Parlon-Star Prime and your star composition as the inner priming layer" sounds like a good idea, and may be the way to go.

 

I'm not making shells at this stage, just simple 3/4" comets shot from a star gun. If that's successful, then CAN shells might be on the cards later down the track (sounds very far away ). Priming without KClO3, KClO4 or Silicon Powder or whatever else that I don't know of, was always going to present a challenge.

 

That's fine - it gives me something to work on.

 

Stix if you can get smokeless powder that's the way to go. I have a purposed spray bottle for priming with n.c. in acetone very thin. As with cut stars, dust both sides of your patty before cutting with mill dust, cut and dry completely (3-4 hours). Then I lay them out on wax paper and spray with the n.c. after which I dump the sheet into my priming box and toss. This prime consists of mill dust with about 8% mgal (80-200). They light pretty reliably.

 

Thanks Roger. That's a lot to take in, but becomes more clear as I read it. I do have a small supply of smokeless powder and have made nc lacquer before, so it seems very doable.

 

My aims and goals are quite modest, but important to me nonetheless. Thanks for sharing your hard earned knowledge.

 

Cheers to all.

[stix]

There's 3 percent decrease in the oxidizer ,but 3 percent increase in the fuel. And your red star formula burns more resin fuel which consumes way more oxygen than dextrin .

Stars burn in the air ,so atmospheric oxygen should be taken into consideration. Most of the star comp is oxygen-deficient.An over-oxidized star will create a big piece of slag.

 

I'm not sure I understand completely. Maybe it's just the wording.

 

Are you saying that that particular formula is not good - and under oxygenated? (for want of a better word). Or are you pointing out that the formula is purposefully under-oxygenated, because whilst streaming through the air with speed, it will gather the oxygen needed, and burn and consume itself without waste?

 

Much to ponder - it's very late here and after midnight.

[PIL]

In the first paragraph ,I'm explaining that the number I've given is correct when SAME AMOUNT of fuel is used.For example,red has 47% fuel .So the percentage of barium nitrate 63.6/(63.6+47)=57.5% .Less red gum means less oxidizer,so 56% is ok.

 

 

Most color star formulas are slightly under-oxygenated to compensate for atmospheric combustion.Seriously under-oxygenated stars produce lampblack，which will add yellow hue to the flame and spoil the color.

 

 

About prime ,I recommend green meal +10% mgal and 8% red iron oxide as inner layer.Thermite components produce molten iron that will ignite the star reliably

 

 

I'm Chinese. Sorry for my not-so-clear English expression.

Edited September 4, 2015 by PIL

[stix]

In the first paragraph ,I'm explaining that the number I've given is correct when SAME AMOUNT of fuel is used.For example,red has 47% fuel .So the percentage of barium nitrate 63.6/(63.6+47)=57.5% .Less red gum means less oxidizer,so 56% is ok.

 

 

Most color star formulas are slightly under-oxygenated to compensate for atmospheric combustion.Seriously under-oxygenated stars produce lampblack，which will add yellow hue to the flame and spoil the color.

 

 

About prime ,I recommend green meal +10% mgal and 8% red iron oxide as inner layer.Thermite components produce molten iron that will ignite the star reliably

 

 

I'm Chinese. Sorry for my not-so-clear English expression.

 

Thanks PIL, it wasn't you, it was me - it was very late. Your English is better than my Chinese - as a matter of fact, your English is probably better than mine

 

I'm trying to get my head around what the various components are there for, so thanks for helping explain things.

 

Cheers.

[stix]

I've just finished making this comp - 1/4" cut stars, and it's been drying (evaporating) for around 1 hr, so still quite soft.

 

Just did a static burn test (small piece) on my 'pyro plate' and I have to say that this is 'retina burning'. I mean it, in it's absolute sense. This test was done during daylight, and when lit and looked at, I still saw the image of it when I looked away. Certainly a brilliant Red!!

 

It left some slag, but I imagine that would not be the case when airborne - but nevertheless, that's irrelevant because it is a very nice Red indeed!

 

RED STAR

53 Strontium Nitrate

19 Magnalium

17 Parlon

11 Red gum

+ 22% Acetone

 

Cheers.

[clarkie752]

After reading this thread I am wondering...... If you used water and dextrin to bind this formula wouldn't you run a risk of the stars being driven in since the stronium/barium nitrate can be hydroscopic?? I have always bound red and green nitrate stars with parlon and acetone.

[Sparx88]

Though my all time favorite red is Ruby Red with "all" it's ingredi-ants, magnalium red or whatever other name, for me gets fueled with sulfur not red gum and yes bound with acetone, or more recently MEK. No strings attached.

[stix]

After reading this thread I am wondering...... If you used water and dextrin to bind this formula wouldn't you run a risk of the stars being driven in since the stronium/barium nitrate can be hydroscopic?? I have always bound red and green nitrate stars with parlon and acetone.

 

Clarky, I'm not sure if strontium/barium are any more hygroscopic than KNO3. I did some reading on this forum from about eight yrs ago and it was pointed out that they are not - but if someone else with more experience could answer that question, I'm sure it would be useful.

 

Then again, this is a possible explanation:

 

I would go for the dextrin and water. Where stars with a high charcoal content might take 7+ days to dry, colored stars with water take much less time. From small (5mm cubes) to big (12mm, half of an inch cubes) it takes approximatly 1-4 days to dry, if you don't overwet. Good pumped stars might even take less time, but they take more time to make. Parlon bound stars might also create an orange glowing "skeleton" afer the star burns out. You might see this in the air, and it's like a really ugly color change. I've had this with a green comp very similar to yours.

 

EDIT: When I say water, I mean water with some alcohol

 

Andres mentions water/alcohol. (I'll say 75/25) I'm sure that I read somewhere, but with another composition, that this idea is foolish. In that 75% wouldn't be enough water to activate the dextrin and 25% denatured alcohol is not enough to dissolve the redgum.

 

It seems a reasonable prospect to me. If the redgum can be dissolved enough, then it may protect the comp from being too hygroscopic?

 

I'm sure this has already been experimented with many times in the past and a consensus reached - if this can be shed light on, that would be appreciated.

 

Cheers.

Edited September 8, 2015 by stix