Sciencemadness Discussion Board

At-Home Research Study (Pyrotechnic Adhesives Comparison in Salutes)

Armistice19 - 22-7-2015 at 16:08

Hello all,

I would like to take the time now to inform any and all interested individuals, and/or those who would like to offer critique, that I will be conducting somewhat of a “research study” concerning the effectiveness of various common adhesives used in the manufacture of pyrotechnics (specifically salutes). The adhesives will be compared in homemade, and over-the-counter versions.

I plan on starting this particular project on Friday. Unless someone convinces me that research on this topic would be unnecessary, or is aware of such a project already being conducted in a detailed fashion.

The purpose of my project will be to find the BEST OVERALL glue (considering cost, drying time, strength, density, hardness, flexibility, resistance to water, expansion/contraction upon drying, and finally, the noise level of the finished salutes. All pertinent variables will be controlled as much as possible during the course of the study; i.e. a predetermined consistent amount of designated flash powder formula will be used each time, use of tubes of the same dimensions, same amounts of adhesive…etc.)

The glue will be used for completing two combined tasks:

-The manufacturing of paper tubes
-The plugging of said tubes

I aim to find a superfluous all purpose glue that can accomplish both tasks without any modification to the formula between each task.

Furthermore, two plugging techniques will also be observed. The first of which will be with tapered wood plugs in conjunction with the adhesive. The second will only observe the plugging performance of the adhesive when used alone.

The study may or may not include the following materials (and/or any combination thereof):

-Caesin
-SGRS
-Dextrin
-Wheatpaste
-Waterglass
-PVA
-Wood glue
-Hide glue
-Alcohol
-Acetic Acid
-Sodium Bicarbonate
-Calcium Hydroxide
-Water

All results, test methods, lab notes, and other recorded data/observations will be posted in this thread during the corse of the study.

I encourage any of you to please inform me of any suggestions, critiques, or safety considerations that you feel I should be aware of at this time.

*NOTE* (Please, no high cost/high density adhesive suggestions. I am not going to use J-B Weld to make a salute.)

[Edited on 23-7-2015 by Armistice19]

HashtagNever - 22-7-2015 at 19:03

SGRS is most definitely your best bet.

Armistice19 - 22-7-2015 at 19:33

HashtagNever,

Thank you for your suggestion, however, only by word of mouth and beginner pyro-blogs have I found SGRS to be "the best" pyro-adhesive. I imagine SGRS is merely an inexpensive Japanese raw material that is acceptable in performance. Can you prove to me; i.e. site reliable sources that concur SGRS is in fact superior to all other adhesives used for the above purposes? I would be more than happy to read!

kecskesajt - 22-7-2015 at 23:31

In Hungary,we use waterglass for almost anything(except stars).
It doesnt dry that easily but very strong tube will be the product.We make a bounch of paper tubes at once(100-150 pieces)
It expand a little but usable.
Another thing we like is CMC(carboxymethylcellulose).
It doesnt expand very muck but if you make a shell from it and you are not carefull enough it can kill you because its so strong.
Relatevely low cost,maybe ~7 dollars for 1 kg.
The best for tube: Waterglass
---------------------------------------------------------------------------------------------
For plug,the best thing is clay plug.Dry pressed Na or Ca bentonite.Very strong and in explosion you have lesser chance getting hit by it than using wood or gypsum plugs.
But the loudest is with modell gypsum

So the best for salute:Waterglass paper with gypum plug.

Armistice19 - 23-7-2015 at 09:17

Yes I believe waterglass to be a huge contender in this study, however my official hypothesis based on the previously posted considerations, is that our champion glue will consist of a mixture of adhesives. Thus combining the individual properties of interest.

I’m glad you mentioned bentonite/gypsum plugs. I was considering them, but previously believed them to be inferior to wood as far as reaching maximum pressure? Having said that, getting hit by dense enough flying debris is definitely a safety concern.

...Brain snack...
Gypsum:
2.32 g/cc

Wood (Pine):
0.35-0.67 g/cc

Modulus of rupture anyone??

Heart Pine vs. Yellow Pine:
13,340-17,259 PSI

Gypsum 90% vs. Gypsum Plaster:
725-1,067 PSI

Anyone out there know how to calculate the maximum PSI released from a confined given amount of Flash Powder?

Pyro-Alan - 25-7-2015 at 07:13

You need to read these.

Fireworks
The art Science and Techniques, pub. 1988
Takeo Shimizu, PhD, Engr.
Pyrotechnica Pubs.

Chemistry of Pyrotechnics
Basic Principles and Theory 2nd ed., 2011
John Conkling, Christopher Mocella
CRC Press

The Chemistry of Powder and Explosives
Tenney L. Davis, Ph.D.
Two vols. In one book
Angriff Press 1943

The use of adhesives, confinement, formulae for explosion analysis.
Must haves for pyros.

Armistice19 - 26-7-2015 at 12:47

Pyro-Alan,

Thanks for the reading list!

I'm about 3/4 of the way through The Chemistry of Powder & Explosives right now, and once finished, I will be reading the Takeo Shimizu book. Shimizu's work has been recommended far too many times to ignore at this point. I have even heard whispers from other threads/forums that he actually discusses the very subject of pyrotechnic adhesives in depth!


Update:

This past Friday I tested some homemade Casein on a couple of old wooden planks from a Pickett fence (unpainted). After about 12 hours of drying, I was still able to separate the planks with my bare hands. However, this was not the easiest thing in the world to pull apart either. The glue seemed sticky and jelly like rather than a hard crust.

Procedure:

First I warmed up 1 1/2 cups of skim milk to a steam. I then eye-balled about two teaspoons of white distilled vinegar which was immediately stirred in thus separating the whey from the curd. I then added about a spoonful of baking soda to the curd, which I further heated while whisking in tap water. End product was yellowish-white with a "goopy" consistency.


I want to clarify that this attempt was nothing but a rough practice run in order to "get a feel" for the process. Later on tonight I will be making my second attempt. This one will be essentially the same as before, however I will use a graduated cylinder, an analytical scale, and a thermometer. Furthermore, this time all data/observations will be posted (most likely at some point on Tuesday).

[Edited on 26-7-2015 by Armistice19]

aga - 26-7-2015 at 13:00

I'm not a Pyro guy at all, yet i'm intrigued as to How you are going to measure the 'Best' adhesive.

Have you developed a protocol to Scientifically measure their relative performances ?

If not, then i fear that your efforts will be wasted, as the Scientists here will not accept just your word for it : you would have to produce Scientific Data to convince them.

Before pointlessly blowing a lot of stuff up, it would be a good idea to post your testing protocol for people to have a look at, and maybe for you to adapt into a truly Scientific procedure.

Just a thought.

Armistice19 - 26-7-2015 at 17:39

Before I say anything, I will begin with some basic clarification in case there was any miscommunication. The adhesive which creates the loudest salute, for the least amount of money, is (for my purposes) the champion glue.

Aga,

Thanks for your thought! this is exactly why I post my projects on this forum. I believe Benjamin Franklin was correct when he said "Critics are our friends, they show us our faults.”

After re-reading my first original post on this thread, I can see why you would wonder about my testing protocol. The introduction was very unspecific, and the main reason for this is because the specifics of the protocol are still being developed at this time. The introduction was simply meant to give a general idea of what kind of properties of interest I will be observing in the final adhesive (most importantly the decibel level of finished salutes).

Also please keep in mind this is not a professional research study by any means. I don't expect to get published, nor do I expect to be taken seriously by professors/world renown scientists. This is me having fun, and I merely wanted to contribute to sciencemadness after the many years that you all have assisted me in my educational journey.

Anyway, let's get to the good part. Perhaps now I should post a rough general procedure of how I imagine things might go??

1. COST: I plan on saving receipts.

2. DRYING TIME: I plan to be using a hardness durometer every hour on a completely different location on the finished paper tube. Each time hardness is tested, the exact time will be recorded. Once I get 5 readings of the same hardness, I will declare set time. After 12 hours I will test the hardness three last times to get a final average, and compare it to the previous set time.

3. DENSITY: I plan on getting the mass from my scale, and the volume from my graduated cylinder....(you get the idea).

4. EXPANSION/CONTRACTION UPON DRYING: I plan on using digital calipers to measure all dimensions before and after drying.

5. NOISE LEVEL OF FINISHED SALUTE: I plan on using a decibel meter.

Furthermore, the salutes will be standard “Silver Salutes”

1-1/2" Long
1/2" Inner Diameter
10/16" Outer Diameter
1.5 grams of flash powder (standard 70/30 using indian blackhead)

[Edited on 27-7-2015 by Armistice19]

A sad day

Armistice19 - 9-6-2016 at 12:01

Apologies all around everybody. Obviously this project did not go quite as planned. It is with a heavy heart that I announce my favorite private property has been bought up by local government. I no longer have a proper place to conduct these tests. Between that and heavy work loads at the lab, I will be postponing this project until further notice. :(

Armistice19 - 5-8-2016 at 04:51

So I'm thinking about revamping this project slowly, but before I do, I have an extremely important safety question. I understand that having a high humidity environment greatly decreases the chances of a static discharge while mixing FP and during the construction of salutes. But I also know that high humidity can cause the Al powder to begin to evolve hydrogen and form aluminum oxide while releasing small amounts of heat along the way. So which is it? High humidity, or low humidity? Isn't this a catch 22?

My knowledge tells me that during mixing or fabrication of salutes there should be a high humidity, and that pre-mixed FP or finished salutes should be stored in a desiccator sprayed with static guard (which I have already done).

Am I correct here?

I've also heard of people cleaning up FP spills with a sponge and soapy water, which I have also done before, but I've been thinking about that lately and how it could be hazardous for the same reasons stated above. Just concerned right now, as anyone who does this kind of thing should be!

[Edited on 8-5-2016 by Armistice19]

[Edited on 8-5-2016 by Armistice19]

PHILOU Zrealone - 5-8-2016 at 13:39

A little moisture into FP is bad news but a large amount like a soaking wet sponge for a tiny spill is absolutely harmless because there is a lot of water to take up the heat and too little FP to inflame and produce any damage...stil don't trow the sponge afterwards into your FP drum ;):P:)

[Edited on 6-8-2016 by PHILOU Zrealone]

Armistice19 - 5-8-2016 at 14:38

From what I've been reading that makes a lot of sense. Thank you kindly.

Here's an experimental salute I made not too long ago. Currently it is in the desiccator for safety, and because the glue was taking forever to dry! :P (I layed it on extremely thick)

Made from rolled Kraft paper and wheat paste with wooden endplugs. Wheat paste had a little extra sugar, titebond III ultimate wood glue, and 91% first aid grade ispropyl alcohol. There is absolutely NO airspace in the finished product, due to tamping and hammering the final plug in tightly. (I know I'm crazy) :P

Final product was brushed with 3 coats of titebond III ultimate wood glue, and two final large gobs more to cover the end plugs.

Video coming soon.

IMG_20160803_020547365.jpg - 857kB

[Edited on 8-6-2016 by Armistice19]

[Edited on 8-6-2016 by Armistice19]

[Edited on 8-6-2016 by Armistice19]

Bert - 5-8-2016 at 22:53

Shoot. Just fiberglass them, if you want the ultimate hard shell.

And then shoot the same weight of flash in 3 turns of 80 lb. Kraft paper, and be amazed at the lack of huge performance increase vs. huge additional effort to make ridiculously elaborate casings.

Armistice19 - 6-8-2016 at 00:01

Good point,

I really went overkill on that one, but it was more just to see what would happen if I did. We'll see how she performs, I'm expecting it not to be great at this point.

Sounds like the general consensus is that thicker and harder doesn't always mean better. I suppose I've chosen to learn this lesson the hard way.

Hopefully I still get a nice crater though :P

[Edited on 8-6-2016 by Armistice19]

PHILOU Zrealone - 6-8-2016 at 10:22

Wooden plugs...maybe replace with slaked lime/chalk so when bursting it becomes a dust and not a hard projectile...

In fact the tamping and hammering to put as much as possible into the banger is useless...

Commercial hard cardboard "Pirat bangers" with a match head instead of a fuse only contains 1/3 of free flowing flash powder...the 2/3 rest is air...thus it is quite a material economy...instead of 1 banger, you can make 3!

I have made rolled newspaper bangers cylinders with wooden glue...you can make as big, as long and as thick as you want...and it is hard like stone.

[Edited on 6-8-2016 by PHILOU Zrealone]

Armistice19 - 6-8-2016 at 10:45

I haven't tried slaked lime yet, I was thinking about bentonite as another (safer) plugging option as well.

Yes I realize the tamping and hammering can lead to a "blowout" situation. I kind of wanted to see if it would still happen with the thicker harder tube.

I'm intrigued with potential pressure build up with this particular practice device.

I have a 7.5 g polumna from 4th of July in the desiccator as well. I was very disappointed with the polumnas I made this year as they were very "poofy" and far less "bangy" than years past.

[Edited on 8-6-2016 by Armistice19]

PHILOU Zrealone - 6-8-2016 at 11:14

You can spice up lower pyrotechnic compositions with a pinch of dust from silver acetylide nitrato complex (detonating)...of course don't use this for the fuse only for the core charge.
I have done this in démos at univeristy and Bengale fire turned into severe bangers.

Armistice19 - 6-8-2016 at 11:54

Silver Acetylide fuse! LOL jeeze oh man!

But in all seriousness thanks for the warning. It is far better to make sure everyone's safe, rather than assume that I didn't already know not to do that. Ever.

I figure someday I'll do a synth of the stuff, but it's a little out of my league for now. Mostly due to it's instability, and the fact that the hand full of times I made NC were my first real synths. Most of the stuff I create consists of powder binaries (the occasional thermite) smoke compositions, gas/oxygen filled balloons and such. Better to do plenty of reading on it before I attempt it, but sounds pretty neat none the less!

P.S. *Just remembered I have two jugs of calcium hydroxide on the shelf! Time to get crackin' (no pun intended).

[Edited on 8-6-2016 by Armistice19]

[Edited on 8-6-2016 by Armistice19]

PHILOU Zrealone - 6-8-2016 at 13:21

Quote: Originally posted by Armistice19  
Silver Acetylide fuse! LOL jeeze oh man!

But in all seriousness thanks for the warning. It is far better to make sure everyone's safe, rather than assume that I didn't already know not to do that. Ever.

I figure someday I'll do a synth of the stuff, but it's a little out of my league for now. Mostly due to it's instability, and the fact that the hand full of times I made NC were my first real synths. Most of the stuff I create consists of powder binaries (the occasional thermite) smoke compositions, gas/oxygen filled balloons and such. Better to do plenty of reading on it before I attempt it, but sounds pretty neat none the less!

P.S. *Just remembered I have two jugs of calcium hydroxide on the shelf! Time to get crackin' (no pun intended).

Good luck!

Don't forget to wear gloves and googles...Ca(OH)2 is quite basic and dangerous/irritating to skin and eyes when moist...about equivalent to medium concentration NaOH solution...

Armistice19 - 6-8-2016 at 13:39

Quote: Originally posted by PHILOU Zrealone  

Good luck!

Don't forget to wear gloves and googles...Ca(OH)2 is quite basic and dangerous/irritating to skin and eyes when moist...about equivalent to medium concentration NaOH solution...


Thanks!

I figure I'll read the MSDS on the particular stuff I have.

[Edited on 8-6-2016 by Armistice19]

Bert - 6-8-2016 at 20:04

Hitt's flashcrackas, just sayin'-

No end plugs at all, just a small dab of white glue on dry rolled paper, string, flash powder and a fuse. Loud as hell if made with decent dark Aluminum/perchlorate/Sulfur or Antimony sulfide flash.

In the long ago, I saw 1 oz. of such flash loaded in a heavy spiral wound cardboard tube with very strong end plugs shot in a subjective comparison test with the same charge in an oversized version of the flashcracka. All who witnessed these tests prefered the sound quality of the flashcracka, and there was no possibility of case materials becoming a dangerous projectile.

Armistice19 - 6-8-2016 at 20:55

Eeek! Sulfur containing flash powders?

I've honestly only ever read about them, but they also sound out of my league again for now.

I'll try to make one of the earlier mil-spec m-80s if I get enough votes from you guys (but not until you guys give me time to research it properly.)

Heck, I'll even order the antimony sulfide for it too, but not yet. Best give it some time for me to get used to these kinds of projects before I get ahead of myself!

Just finished doing a bit of reading on Thomas Gabriel Hitt and just...wow. What an amazing man!

[Edited on 8-7-2016 by Armistice19]

Bert - 7-8-2016 at 09:07

Old fashioned saietines were made from 3 turns of dry rolled heavy kraft paper, rammed sawdust for end plugs and 2 turns of pasted string to hold it all together. They survived being ejected from a bursting aerial shell and were freaking LOUD with an ounce or so of decent flash, minimal thickness of a tough containment works just fine...

The primary reason for a heavy containment is using too slow a flash for the application, or the need for a lot of durability in handling and shipping. Otherwise, let the flash do the work. Want more noise? Use more flash.

And the dessicator is of questionable utility with perchlorate/Aluminum flash. You are also lowering the tensile strength of the paper by getting it crunchy dry, some have caused rocket cases to fail by treating them like that. I do not keep our several tons of salutes in a dessicator...

Armistice19 - 10-8-2016 at 04:02

Fair enough.

Sounds like what I'm hearing from you guys is that it would be a more relevant/appropriate contribution to the forum if I were to shift my focus away from adhesives and containment methods, and instead begin to experiment with different (more dangerous :() flash formulas, especially since what I'm going for here is decibel level (though brisance is of interest as well). I suppose I'm okay with changing up the original plan of attack with this study, however my main concern was (and still is) safety, and 70/30 KClO4/Al was the safest formula I could find.

Having said all this, I suppose I could begin to maintain a respectful fear for my hobby and still up the ante with new, more powerful/sensitive flash based mixtures at the same time. Though I will need to do a lot of research before these attempts, which will take a considerable amount of time.

So far I hear from you guys a few things.

1. Addition of Sulfur, or Antimony Sulfide (which scares me)
2. Sprucing up the bang with a primary initiator (which scares me even more)
3. Allow for more airspace in the containment

Any other suggestions? All suggestions are welcome, but please notify me of safety concerns.

I have an old ball mill and some 1/4" chrome plated steel media collecting dust somewhere in storage too. I was thinking of further milling the already finely powdered components separately in order to achieve sub-micron particle sizes, though I would have no way of testing the actual particle size :(

I figure after that I could start by diapering together sub-gram quantities. This should give me some time to get a feel for the mixtures, maybe do a couple hammer tests as well, provided I find a decent place to do them.

Bert,

Is it common to fiberglass coat salutes? From what I've read, glass is pretty high on the positive end of the triboelectric series, and polyester resin very low on the negative. Wouldn't that make a high potential for static discharge? I suppose this wouldn't matter if grounded-out during handling though, but still.

Speaking of grounding out, my pipes under my sink are plastic. Anywhere else I could connect my wristband?


[Edited on 8-10-2016 by Armistice19]

[Edited on 8-10-2016 by Armistice19]

Bert - 11-8-2016 at 13:45

Connect an anti static wristband to a solid ground, which could be a ground rod, driven into the earth a good ways... Please connect it through a megohm range RESISTOR, not directly. Ditto any anti static dissipative work surface, flooring, etc.

I hope you are not making flash indoors, in an apartment building, on the upper floor of your parents house, etc. You should be outdoors or in a minimal shelter away from everyone and everything that you could dammage.

Quote:
Sounds like what I'm hearing from you guys is that it would be a more relevant/appropriate contribution to the forum if I were to shift my focus away from adhesives and containment methods, and instead begin to experiment with different (more dangerous :() flash formulas,


Believe me, you do not need to contribute to this forum by screwing around with trying to make hyperflash, nor are you likely to do more than reinvent the wheel by trying.

No one wants you to risk your life, and you should do nothing that makes you nervous. 70:30 works just fine for much of the pyrotechnics industry, particle size and mixing can do a great deal to adjust performance.

Brissance? Not what flash is for, you are generating noise, not cutting steel here...

Initiating flash with primaries? Yes, some have substituted 90:10 ammonium nitrate/Aluminum for flash and used a cap/booster in very large salutes and bottom shots, both for economy and to have a salute mixture that would not blow a gun if the case leaked lift gasses, at least if it did not leak into the time fuse/passfire/cap assembly- I would not care to experience a round trip and one of these detonating on the ground, however.

Flash is too fuel rich for an easily detonable material, and you have not increased safety but added an additional risk from including a primary in your firing train. Worst of both worlds, please do not mix technologies, choose HE and cap, or choose flash and a flame initiator.

Pete Cermak of Banner Fireworks did coat large salutes and bottom shots with fiberglass & resin several decades back (he had worked in an auto body shop, and was used to working with the materials). No one else I know of does so now, at least commercially. Pete did not die from doing so, as he was apparently destined to hang.

Maybe it is time to read a lot more, rather than experiment.

XeonTheMGPony - 13-8-2016 at 10:03

I use nitro cotton in acetone as a glue for allot of my end caps to ensure it separates once it has don its job, physics will help you more for sound, by using a captive air chamber to increase the pressure waves amplitude for a bigger sounding boom using less material.


glue really doesn't matter at the speed it goes at gum will work, the emphasis is on the geometry of the charge and even internal pressure distribution. again I used shellac/varnish as it is what I had when making my charges

As stated do more reading, no need to mess with well established methods!

Some bursting charges used: An 95/5 carbon milled set off with a fullimate cap, Flash powder, fine black powder.

depends on the effect you're after, flash and black will give a deeper boom, the H.E. gives a sharper crack.

I am in no way even a professional on the subject but I have made a good bit of charges for aerial display and had moderat success and I did it by following established methodes, with just small personal twists for colour and casing methods.

Armistice19 - 18-8-2016 at 18:31

Thanks everyone for your advice. Much appreciated.

I think I would be comfortable with diapering in some sulfur/antimony trisulfide to the mix next time I have a free, uninterrupted day. Specifically I would like to try Thunder Flash formula # 3. On page 40 of the complete book of flash powder, as again, I am primarily going for decibel level here. As far as adding silver acetylide to my flash, I have decided not to do so, as this would be "mixing technologies" as Bert mentioned, or altering “well established methods” as Xeon said. Not to put down the suggestion from PHILOU, as it sounds like you achieved some pretty high decibel levels! But I’m just not comfortable with that for now.

Yes flash powder is not really for brisance at all, but that sure as heck doesn't mean I don’t like observing what little it has, and I do think thicker walled tubing may affect it slightly.

Personally, I'm not sure watching steel being cut in half by semtex would be interesting to me right now. But the small dirt craters and shattered plywood I have observed from flash devices is actually quite fascinating to me at this time.

Read more? Experiment less? Sounds like just what I need right now! Any good reads that anyone has to suggest? (other than the ones already suggested by pyro-alan at the beginning of this thread, which I will be reading shortly.)

[Edited on 8-19-2016 by Armistice19]

[Edited on 8-19-2016 by Armistice19]

[Edited on 8-19-2016 by Armistice19]