Salutes and confinement

[dangerousamateur]

I hope I don't get flamed for this one.

 

Well, I've seen lots of salutes, commercial and also homemade stuff on YT, that where confined VERY strong.

I wonder if the confinement has any effect on the sound.

My feeling is that once you have reached a certain level of confinement, the sound does not change any more. If you move to amounts +10g even very thin casings work, even with nitrate based flash.

 

Also, I wonder if it has any effect how much the casing is filled.

 

In general, once the reaction/detonation velocity reaches a certain level, the sound does not change anymore. Or does it? As you can imagine, one cannot test theese things very often without getting in trouble.

 

I'm especially keen of rockets, where the casing is not objected to any mortar blast, it just needs to be strong enough to be safe to handle. Since any stronger casing is just dead weight to carry, I'd rather invest my payload capability in more energetic material Same goes for unnecessary voluminous headers.

[dagabu]

In order to go forward, lets go back some. The main purpose for reports on rockets has been to mark the end of it's travel, more importantly nowadays is its ability to bust the tube and stick so that the missile coming back down is less dangerous. The confinement and sound they produce have not been really high on the priority list.

 

GBs are often spiked and have thick hard cases to contain the comp and many have lots of filler added. These salutes have a markedly sharper sound than a Gabe Morte of the same size but it is the optimized mixes that make the best sound with high dB and low tones.

 

In short, yes confinement to a certain level increases the report but diminishes at a certain point. As far as how far the case needs to be filled, well, that continues to be a sore spot for some. No need to cut the ends off the roast...

 

-dag

[dan999ification]

it depends on the vit f, some will self confine and need little confinement to perform as well as standard f but we wont go there, imho thicker tubes will produce more db, a bit like uncorking a bottle, if the pressure is allowed to escape slowly, not much sound, if it is released quickly you get the idea, more pressure in a report or allowing it to build to me equals a faster release.

The filling dependant on casing length, if it is long ( more than ten id's ) and full or even tamped down the composition may not be consumed before the casing splits more so with heavy comps, but it is said to be louder not quite full, i think its best loose unless you need to maximise the amount of comp, the master and others here who make cap plug reports settle the comp to fit one gram in.

Paper does have its limits and im sure past a certain thickness once the walls are subjected to high enough pressure to compress the first few turns its all over, other materials with higher burst strength ive no doubt are louder.

All in all theres a reason why they are normally short and fat, traditional italian builders use a dry rolled stack of paper for the tube, safety being one reason, heavy tubes will come down heavy still if they are part broken, dry rolled paper will flutter.

 

Dan.

This is all just my opinion, and i hope to not upset the balance here i consider this as discussion and not how to.

 

 

[dagabu]

it depends on the vit f, some will self confine and need little confinement to perform as well as standard f but we wont go there, imho thicker tubes will produce more db, a bit like uncorking a bottle, if the pressure is allowed to escape slowly, not much sound, if it is released quickly you get the idea, more pressure in a report or allowing it to build to me equals a faster release.

The filling dependant on casing length, if it is long ( more than ten id's ) and full or even tamped down the composition may not be consumed before the casing splits more so with heavy comps, but it is said to be louder not quite full, i think its best loose unless you need to maximise the amount of comp, the master and others here who make cap plug reports settle the comp to fit one gram in.

Paper does have its limits and im sure past a certain thickness once the walls are subjected to high enough pressure to compress the first few turns its all over, other materials with higher burst strength ive no doubt are louder.

All in all theres a reason why they are normally short and fat, traditional italian builders use a dry rolled stack of paper for the tube, safety being one reason, heavy tubes will come down heavy still if they are part broken, dry rolled paper will flutter.

 

Dan.

This is all just my opinion, and i hope to not upset the balance here i consider this as discussion and not how to.

 

10 IDs? WOW! the rule at the shoot I am going to this month is no more than X3 the ID max.

 

-dag

[dan999ification]

sorry dag i wasnt going by rules, just that it may not be used if the casing is too long and very full, ten id's would be wastefull and not recommend, some tubers make them longer, i dont see why, short, fat and thick is the way i like em.

Ferocious titanium salutes ( title ) ti donuts were around 8 id's, salamis but i suspect loose powder backing up the theory of longer needing loose comp if thats is actually how they were made, too wastefull otherwise.

2 or 3 id's is all that is needed.

 

Dan.

Edited October 3, 2012 by dan999ification

[dagabu]

Agreed.

 

-dag

[FREAKYDUTCHMEN]

Piromaniac, the spanish mascletas use thin walled spiral wound tubes for their ground salutes, the tubes are only used to hold the 7:3 or 3:1 etc flash together. The fuse, in many cases quickmatch, ends in the middle of the salute. The sound of these salutes have a really low tone which you might not expect. It's the thin casing that prevents the sharp tone. Because when the thin wall erupts from the detonation not the whole amount of flash powder has burned yet, so even after the ignition and the eruption of the tube the actual bang goes on which makes the soundwave longer. If the spanish would have used thick walled tubes every spectator would be deaf after one mascleta.

If you want a nice deep salute on your I'd recommend to use a thin walled tube containing at least 15-20 grams of 7:3 flashpowder and maybe even more if you don't really care about amounts. If you don't want to put too much flash powder on a rocket you require more confinement which ends in a sharper tone.

Big question still is what higher distances do with the sound. The story here above is about salutes on the ground, but I also now that 7:3 flash in thin walled plastic rocket headers 1mm wall thickness and kind of elastic) also sound really really nice.

Edited October 4, 2012 by FREAKYDUTCHMEN

[dangerousamateur]

I'm not talking about a stickbreaking bottomshot, but a pure salute rocket.

The only intent is to have an airal salute.

Only for new years eve of corse, it won't attract to much attention then.

 

I tried some thin walled headers last year, but the sound was rather sharp, high pitched.

 

 

Now check this out:

 

Turn up the subwoofer

 

"Only" about 50g of Flash and a rather massive tube.

http://img855.imageshack.us/img855/9162/zinko.jpg

 

Thats the sound i want. Not that ear hurting m80 sound but rather a concussion.

 

I like to strip one of these and look whats inside. Slow flash?

[dan999ification]

probably slow the pitch is different, slow ( er ) pressure build up gives less crack and more thunder imo.

 

Dan.

[usapyro]

I wonder if a very long thin salute would create a deeper sound than a short stubby one...

 

Oh wait, that reminds me of when I nearly deafened myself with 20' of flashcord... Damn that crap is louddd...

Edited October 7, 2012 by usapyro

[dan999ification]

you have a problem scott, this forum is for discussion not encouraging misuse, what do you expect?

Please leave your attitude in your threads.

 

Dan.

[dangerousamateur]

probably slow the pitch is different, slow ( er ) pressure build up gives less crack and more thunder imo.

Yes, but in that massive confinement? Must be damn slow flash then...

 

I wonder if a very long thin salute would create a deeper sound than a short stubby one...

Somebody needs to try it out I would, if it wasnt so load

[propyro]

I'm new to posting online,and this forum seemed as good or better than a lot of others.

My knowledge and experience is with ground salutes only,I'll eventually get into other areas

of pyrotechnics later on.

I've been making/experimenting with salutes for about 4yrs.The flash that is the industry standard

is KCLO4/AL usually reccomended in a 70:30 mix.This is the safest (most stable) and the only mix

I've used.I haven't had the need to add anything else,except cab-o-sil,which I recommend even if the perc you use

already has this added as anti-cake.My preferred mix is -325 mesh perc/w cab-o-sil and a mix of Ind. Blk 2 micron with star molecule 1.5 micron jagged

flake,both the Al's are coated flake.Whith these fine chems I use a roughly 2:1 mix,by the way the more flash in the tube the more explosive,this I do know for a fact.

 

100g batch would be as follows:

potassium perchlorate/w Cab 67g

Indian Blk 2micron 16.5g

Star Molecule 1.5 micron 16.5

 

the reason I mix the ALs is it seems to give a good balance of a loud crack and a lower bass sound.

My thoughts are, why mess with sulfur and antimony trisulfide and all the rest of the myriad formulas out there for FP

this mix is as safe as flash gets and I will tell you from personal experience it is extremely powerful.

No FP whatever the mix achieves detonation as it is not a HE, but this mix sounds like one especially around 20-30g.

[CrossOut]

From my experience, confinement has little change in the sound of a salute.. the only thing that confinement really changes is the amplitude or loudness.. and at that its only a little change. for example if you take 50 grams of FP and put it in a moderately thick tube vs one that is twice the thickness, the sound will be only a tiny bit louder. that that even may only be psychological.

 

what i found is the only thing that can really change the sound of a salute is 1 the amount of FP used.. and 2 the composition your using.... faster FP's will produce a crisp loud crack where as slower flashes will produce deeper toned boom's

 

The shape of the container can also have a mild effect ranging form long cylindrical vs spherical.. it seems that spherical produces a little louder sound which also makes sense theoretically. a sphere is always a super critical shape for most chemical and nuclear reactions.

 

in general flash powder will always create more of a crack sound.. BP will create a nice deep boom sound.. buy keep in mind that it wont sound as loud.. the decibel system is based on a scale of 1*10^x where intensity is increased 10 times before you notice an increase in volume.. additionally this system occurs the same with lower pitched sounds. if you were to produce a noise of 10 decibels of a high frequency sound and 10 decibels of a low frequency sound, the higher frequency will always sound louder and higher frequency sound will have more energy behind it.

Edited February 1, 2013 by CrossOut

[dynomike1]

Ok i am confused on something. There two terms that i am not familiar with.

 

Cab o sill

 

Star molecule 1.5 micron 16.5

 

Ok maybe i do.

Edited February 1, 2013 by dynomike1

[MrB]

I've seen some really crazy salute casings from commercial players, where they use tubes with almost inch thick walls, and then pretty much just a single cardboard sheet as top/bottom. Shell is 100% filled, by using a empty shell as a scoop, and just "scraping of" the top to make sure it's an even fill. Always combined with a cylinder shell, soaking up the thump from the launch, most the time with a short delay between the shell, and the salute. The usual paper wrapping, and heavy spiking of the "shell" half of the combo. The result is a deep rumbling salute using the industry standard KCLO4/AL flash.

 

As far as they told me, the thick tube walls are there just so they can spike the darn thing, if they had a good way the'd just use a thin-wall tube, saving weight, and money.

B!

[nater]

MrB,

 

Sounds like you are describing a fairly standard color and report shell. I can't say I have seen a commercial one that impressed me too much and certainly not the Chinese ones. Limitations from ports and transport laws make this effect hard for commercial use anymore due to the bottom shot.

 

I have only made a couple of these so far using hand rolled casings for the report. Although I have been trying to get good confinement with BP for the nice deep tone. I understand the thickness of the salute casing serves to give property confinement as well as building up the report to serve as the case former for the color break of the shell. It also serves to save money on expensive aluminum since you will use less to fill it.

[mikeee]

Cab-o-sil

Fumed silica is made from flame pyrolysis of silicon tetrachloride or from quartz sand vaporized in a 3000°C electric arc.[1] Major global producers are Evonik (who sells it under the name Aerosil®), Cabot Corporation (Cab-O-Sil®) and Wacker Chemie-Dow Corning.

.

Star Molecule™ Aluminum Powder IS the HOTTEST ALUMINUM POWDER for sale. Star Molecule™ is a military grade aluminum powder that exceeds the performance of any other POWDERED ALUMINUM you can buy.

.

 

 

 

 

[MrB]

Sounds like you are describing a fairly standard color and report shell.

Yeah, i suspect it's pretty standard. I just wanted to cry when i saw the thick tube being closed of with what essentially is a cardboard backing for a new shirt... But then i'm fond of the sharp crack rather then the deep rumble salutes.

 

I can't say I have seen a commercial one that impressed me too much and certainly not the Chinese ones.

This one was "a swedish design" but as you say, i suspect it's a common design for many reasons. I didn't provide it as a "glorious example of great design" but more like "anything works, really". But i still think a thicker end-plug would be good.

 

I understand the thickness of the salute casing serves to give property confinement as well as building up the report to serve as the case former for the color break of the shell. It also serves to save money on expensive aluminum since you will use less to fill it.

Yeah, these are pretty much all the reasons i can think of when it comes to why they do it this way.

 

B!

[flying fish]

If I understand correctly it sounds like with this Swedish (fish..y) method they pack it tight so that they can use thin end disks and rely on the contents for support. I guess it works, but thicken the end disk and maybe put a center support will make it safer, and you can avoid open mixing the flash and don't have to "scrape it off the top." For that matter anything that is scraped flush should be inert packing material (like sawdust), not flash!

 

For me one of the key advantages to using machine cores is being able to binary mix the flash (much safer). If I was going to forego this I'd just hand roll it.

[dynomike1]

Cab-o-sil

Fumed silica is made from flame pyrolysis of silicon tetrachloride or from quartz sand vaporized in a 3000°C electric arc.[1] Major global producers are Evonik (who sells it under the name Aerosil®), Cabot Corporation (Cab-O-Sil®) and Wacker Chemie-Dow Corning.

.

Star Molecule™ Aluminum Powder IS the HOTTEST ALUMINUM POWDER for sale. Star Molecule™ is a military grade aluminum powder that exceeds the performance of any other POWDERED ALUMINUM you can buy.

.

I guess that left me out.

[Algenco]

I don't see a need for Cab o sil, what purpose would it serve in a salute?

 

the perc won't clump once it's mixed with Al

[TritonPyro]

Hi Dan, I guess you have seen the FP crackers and large ground salutes that are available from Europe on the net? They are being used in my neck of the woods ( in UK ) and are incredibly loud. That's it, they are just noise makers. I really think that given time, metal powders and oxidisers will have a ban. The ease of making FP and the people that are irresponsibly making it will almost guarantee it. Sad day for star shell builders and it has taken me long time to build trust amongst my neighbours, to the extent they ask me to tell me what time at night am I testing so they can watch.

[Simoski]

One can easily make a 1g BP / H3 /FP salute by folding a strip of paper into a triangle shape using 45 ° folds. Put the BP / H3 / FP in with the fuse after three folds, then keep folding at 45° till the paper strip is consumed. Glue the triangle shut, light the fuse and throw.

 

As for the sound, a louder bang is observed with better confinement, that has tighter folds, more folds and more glue.

 

When I was a kid we used to add confinement to our crackers to make them louder, id est by binding them with more paper and electrical insulation tape. What I noticed is that you can over do it, by over confining with tons of tape the cracker would not go off

Edited March 22, 2018 by Simoski

[vinny1892]

I hope I don't get flamed for this one.

 

Well, I've seen lots of salutes, commercial and also homemade stuff on YT, that where confined VERY strong.

I wonder if the confinement has any effect on the sound.

My feeling is that once you have reached a certain level of confinement, the sound does not change any more. If you move to amounts +10g even very thin casings work, even with nitrate based flash.

 

Also, I wonder if it has any effect how much the casing is filled.

 

In general, once the reaction/detonation velocity reaches a certain level, the sound does not change anymore. Or does it? As you can imagine, one cannot test theese things very often without getting in trouble.

 

I'm especially keen of rockets, where the casing is not objected to any mortar blast, it just needs to be strong enough to be safe to handle. Since any stronger casing is just dead weight to carry, I'd rather invest my payload capability in more energetic material Same goes for unnecessary voluminous headers.

 

ive made a few with just the standard three wraps of gum tape. I have also made them with about a 1/4 inch wrap. they were hard as a rock. the payload was about 35g of flash in a 2 inch canister for both salutes. one sounded like a stick of tnt going off the other just a nice bang.