10 replies to this topic

[dave]

ok,

not many people here seem to be into smokes, but i am really having trouble getting what should work to work.
i felt like a bit of research into alternatives to colophony and ammonium chloride (which work perfectly well) to satisfy my curiosity really.

cinnamic acid is cited in USpatent 4032374 june 28 1977, douda et al,

basically the formulation quoted is around the following

cinnamic acid 48
potasium chlorate 29
sucrose 12
sod. bicarbonate 7
diatomite silica 4
binder (nc) +2 to 5

i have it on authority from someone in the industry that cinnamic acid can produce a very good, thick ,dense smoke, and is used in low toxicity military smokes
but can i get it to work !!
i admit i have left out the silica, but from what i,ve seen, simply tamped into a tube, its c**p.

i have tried adjusting the chlorate sugar ratio, lowering the ca level, to no effect
i think I AM MISSING SOMETHING HERE.
any comments from the industry / elsewhere welcome, pm if necessary
i would attach the patent but dont know how to ? can it be done ?

dave

[phildunford]

Is it burning?

Some mixtures need to be in a container that only has small holes to stop real burning taking place & allow the formation of smoke.

Flame can destroy the smoke...

Edited by phildunford, 16 November 2010 - 02:34 PM.

[Creepin_pyro]

Is it burning?

Some mixtures need to be in a container that only has small holes to stop real burning taking place & allow the formation of smoke.

Flame can destroy the smoke...

Sounds about right, the patent mentions that 'after ignition the flame was extinguished', so presumably they had not addressed the casing issue to make a finished product. It also calls for a first fire to be used.

Dave, I'd try using a proper smoke casing with baffles, not sure about a good way to extinguish the flame manually.

[dave]

Sounds about right, the patent mentions that 'after ignition the flame was extinguished', so presumably they had not addressed the casing issue to make a finished product. It also calls for a first fire to be used.

Dave, I'd try using a proper smoke casing with baffles, not sure about a good way to extinguish the flame manually.

phil, creepin pyro,
thanks for your replies ....... keep them coming.............

yes, i am aware that the vapour needs to cool to produce the smoke.
sorry i should have included that i have tried loosely tamped composition with small exit orifice ~ 6mm
and also a compressed column with central core and exit hole ~6mm.

i've just increased the chlorate to sucrose ration to 3:1, with 45% cinnamic acid

result, ......more reliable ignition but no real thick smoke at all ???.........very strange !
and the cinamic acid is from a reputable source..........all materials finely ground (individually !)

this is now annoying me............coloured smokes are far easier compared to this.

dave

[martyn]

From The preparatory manual of black powder and pyrotechnics

This is above my head - I just follow recepies!

Non toxic smoke generating composition for use in various training operations.

71.7% Trans-cinnamic acid
12.3% Potassium Chlorate
5.2% Sucrose
4.9% Cellulose Nitrate
3.8% Sodium Bicarbonate
1.9% diatomic Silica
0.2% impurities !???
Acetone (26g of Cellulose Nitrate to 150ml of acetone)

Blend to a uniform powder
Dissolve cellulose Nitrate in Acetone and blend into the other blended components, and press the stiff mass into any desired tube or container.
Should be ignited with a suitable ignition mixture.

ok,

not many people here seem to be into smokes, but i am really having trouble getting what should work to work.
i felt like a bit of research into alternatives to colophony and ammonium chloride (which work perfectly well) to satisfy my curiosity really.

cinnamic acid is cited in USpatent 4032374 june 28 1977, douda et al,

basically the formulation quoted is around the following

cinnamic acid 48
potasium chlorate 29
sucrose 12
sod. bicarbonate 7
diatomite silica 4
binder (nc) +2 to 5

i have it on authority from someone in the industry that cinnamic acid can produce a very good, thick ,dense smoke, and is used in low toxicity military smokes
but can i get it to work !!
i admit i have left out the silica, but from what i,ve seen, simply tamped into a tube, its c**p.

i have tried adjusting the chlorate sugar ratio, lowering the ca level, to no effect
i think I AM MISSING SOMETHING HERE.
any comments from the industry / elsewhere welcome, pm if necessary
i would attach the patent but dont know how to ? can it be done ?

dave

[dave]

[quote name='martyn' timestamp='1290122543' post='70664']
From The preparatory manual of black powder and pyrotechnics

This is above my head - I just follow recepies!

Non toxic smoke generating composition for use in various training operations.

71.7% Trans-cinnamic acid
12.3% Potassium Chlorate
5.2% Sucrose
4.9% Cellulose Nitrate
3.8% Sodium Bicarbonate
1.9% diatomic Silica
0.2% impurities !???
Acetone (26g of Cellulose Nitrate to 150ml of acetone)

Blend to a uniform powder
Dissolve cellulose Nitrate in Acetone and blend into the other blended components, and press the stiff mass into any desired tube or container.
Should be ignited with a suitable ignition mixture.

martyn,

that looks like its from the same patent...........frankly i'm begining to question it.........although it is in black and white, AND there are products out there using it
the problem seems to be that the formulation seems to be vastly under powered with the chlorate sucrose heating mixture.
it only seems self sustaining at high chorate to sucrose ratios (3:1) and relatively low cinnamic acid levels (45%) with no dense smoke production

cinnamic acid also seems to melt (~130c) rather than sublime, which i dont think helps matters (it boils ~400c)
if it is not self sustaining as a loosly tamped powder (in tube with small 6mm orifice) i cant see it will be any better when compressed
(and i have tried compressed core burners)

this is purely an academic excercise for my own interest since i have other cheaper mixes that work fine.

i dont like to be beaten but i have a feeling without extra help, from someone who is familiar with the composition, i may be stuck

dave

[dave]

eh eh

i'm smokin man !
managed to get a 55% cinnamic acid mix to produce......THICK DENSE WHITE SMOKE !!!

it needs a very hot igniter (used lead tetroxide/silicon as a test), now trying out a few alternatives.

( i have to say colophony mixes are a lot simpler)

dave

[Mumbles]

I was actually thinking that the comp didn't have enough fuel in it. I was thinking of these compositions as a typical colored smoke, just with white dye If you compare to something that may be more typical of a colored smoke, you may come to something like the following:

trans-cinnamic acid - 45
Potassium Chlorate - 28
Lactose/sucrose - 20
Carbonate of choice - 7

I've seen chlorate:sugar:carbonate ratios as high as 1:1:1. The 3:1 was actually rather odd for me to see. Smokes are a little odd to think about for me in terms of a typical 100% ratios as the smoke dye really isn't part of the burning composition. The ratio of sugar and chlorate is really what the composition is, and the rest is vaporized. Depending on the dye, it's level can be anywhere between about 35 and 70%. I usually start with the above composition and play with the dye content until it looks good. Don't ask me why, but the 28:20:7 ratio always seems to work better for me than 30:20 or 30:20:5. Trans-cinnamic acid looks like it should be more stable to extra heat than some of the more common other dyes.

[dave]

I was actually thinking that the comp didn't have enough fuel in it. I was thinking of these compositions as a typical colored smoke, just with white dye If you compare to something that may be more typical of a colored smoke, you may come to something like the following:

trans-cinnamic acid - 45
Potassium Chlorate - 28
Lactose/sucrose - 20
Carbonate of choice - 7

I've seen chlorate:sugar:carbonate ratios as high as 1:1:1. The 3:1 was actually rather odd for me to see. Smokes are a little odd to think about for me in terms of a typical 100% ratios as the smoke dye really isn't part of the burning composition. The ratio of sugar and chlorate is really what the composition is, and the rest is vaporized. Depending on the dye, it's level can be anywhere between about 35 and 70%. I usually start with the above composition and play with the dye content until it looks good. Don't ask me why, but the 28:20:7 ratio always seems to work better for me than 30:20 or 30:20:5. Trans-cinnamic acid looks like it should be more stable to extra heat than some of the more common other dyes.

hi mumbles,
yes i agree to a point.
for coloured smokes i would tend to use the more usual chlorate to sugar ratio of 1.5 to 1.(in the patent quoted its about 2.3 to 1)
but cinnamic acid is not a dye and seems to behave very much differently in the mix, it seems much more exacting on conditions.
i'm stil trying to tweak it but its been so damn cold lately its put me off.
light magnesium carbonate seems better than the sod bicarb(not that i store the mixtures,) but i seem to recall mag chlorate is hygroscopic, should it form.
easier to mix in and its more "bulky"
c.a. melts at 134 and boils at 300c, so unlike the dyes it does not appear to sublime as such, i think thats a key difference.
from my understanding in the search for a "low" toxicity smoke the brits went with ca and the yanks went with terephthalic acid.
from a formulation point of view i think the ta was probably easier to develop, since i believe that does sublime (melts at 300c sublimes at 400c)

................more mixes to test

dave

[dave]

I was actually thinking that the comp didn't have enough fuel in it. I was thinking of these compositions as a typical colored smoke, just with white dye If you compare to something that may be more typical of a colored smoke, you may come to something like the following:

trans-cinnamic acid - 45
Potassium Chlorate - 28
Lactose/sucrose - 20
Carbonate of choice - 7

I've seen chlorate:sugar:carbonate ratios as high as 1:1:1. The 3:1 was actually rather odd for me to see. Smokes are a little odd to think about for me in terms of a typical 100% ratios as the smoke dye really isn't part of the burning composition. The ratio of sugar and chlorate is really what the composition is, and the rest is vaporized. Depending on the dye, it's level can be anywhere between about 35 and 70%. I usually start with the above composition and play with the dye content until it looks good. Don't ask me why, but the 28:20:7 ratio always seems to work better for me than 30:20 or 30:20:5. Trans-cinnamic acid looks like it should be more stable to extra heat than some of the more common other dyes.

mumbles,

you may be correct regarding the fuel (sugar) level in the mix.
i have just tried a formula from lancasters 3rd edition , page326, and its the best smoker yet.
not a quick burn or high emission rate, but a smooth steady thick smoke is produced and its easily ignited.
this was as an end burner and a hard solid ash is produced which can lead to pressure build up and some expulsion of remaining mix.
i might try it as a core burner and thus reduce the "ash path" as it were, simply to try and reduce the pressure build up.

lancaster 3rd edition, page 326

cinnamic acid..............................27
pot chlorate..................................29
lactose..........................................29
kaolin............................................15

the saga continues.........

dave

[dave]

heres a video of the latest cinnamic acid formulation, its a real belcher !!

tube id 1", with 6mm core, single ended emmision
it shows pulsating emmision which i have observed in some utube vids on the m83 terephthalic acid smoke grenade
a bit like a less violent whistle mechanism perhaps.

dave