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good slow burning fountain fuel?


klachner

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Hello,

I am searching after a good composition for fountains, which burns slow and therefore long, and which has enough power to make a good effect. All the comps I found online didn´t have any informations about burning speed... I recently made some fountains with normal black powder and 10% ti, the tubes were 10cm long and 3cm ID, and the nozzle was 1cm in diameter. The effect was great and good in height, but although they had 50g they only burned about 5 seconds long... How could I improve the fuel so it will burn slower? Maybe adding more Charcoal or something like that? I would like to have a "base" composition, to which I can add different effects, like titanium, al flitter, little stars and stuff

Any ideas?

Edited by klachner
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You can have power or duration but not both. Adding charcoal both calms and lengthens the burn in a BP based comp.

I keep several colored perc based gerb comps that I can mix for different colors that burn so long you have to shorten the tubes sometimes to prevent burn through. A 5/8" tube 6" long will burn nearly thirty seconds with brilliant color and great itanium sparks.

I got them from FW.com but Ned originally posted on SL here:

http://www.skylighter.com/fireworks/how-to-make/colored-firework-fountains.asp

Edited by OldMarine
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hm ok thank you so i will try adding more charcoal, until the effect isn´t powerful enough any more. I already came across these colored fountains, but at the moment I want to make some which don´t make too much color by the fuel, because I want to have the little colored microstars and titanium as effect only

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Make a very slow BP with coarse charcoal in an open ended tube then begin increasing the fine coal to coarse ratio until that un-nozzled tube will give around 5 feet of plume. Ram that final comp in a nozzled tube and I bet you'll have something very close to what you are looking for. You should be good with a nozzle around 1/3 the tube ID unless your microstars are over 1/16".

I love fountains with a passion!

 

Edit: My math sucks but your tubes are only about 4" long? The best way to extend burn time is to extend your tubes until they start to burn through and then back off a bit on length. Use the same comp you are using now and try it in a 6" tube and go from there!

Edited by OldMarine
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I`d also go for a smaller id but longer tube, the 30mm ~1.25" id will have a large flame front that`ll soon burn through 50g of comp.

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A reasonable size cone fountain, retail in the UK, contains 500 to 1000grams of compound, a 50g fountain will be small when compared! Fountains are basically slow BP or poor BP! The sparks can be microstars or granular charcoal, or any of several metals in moderate powder form (Fe, MagAl, Ti etc). Anything that came from first attempts at BP is a base for fountain comp! Good meal powder with 2 - 20% added fine, or assorted charcoal is a good start too. However "impressive" always means lots of powder.

 

Parallel tubed fountains run at a steady height, cone fountains should grow as they burn. You can have changing colours by compound changes as the tube is filled and can change the colour of the sparkles by putting different microstars in the mix at different heights.

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Small devices are GOOD especially for testing, if it's big and it fails there's usually hurt and fallout, if it's small the hurt and fallout is less. When you get good then bigger is fine,

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Here are my first two 1"x6" titanium gerbs made with screen mixed BP using commercial airfloat charcoal +10% Ti:

 

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  • 1 month later...
One thing I do to slow down bp compositions in fountains is to mix some CaCO3 under' then bind it with a pingpong ball based nc -acetone mi (THICK! As few acetone as possible!) and then add the Ti or the microstars, finally hand pressed into the tube. Couldnt give you some burning time, but it really slows down the thing, without affecting the effect too much. Only problem is the the drying time. If you try different proportions of CaCO3, you should find what you re looking for. Personnally, I also use additional charcoal or lampblack for slowing down, but they always add the golden-orange spray effect, and sometime we don t want this effect.
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If you are using the NC to keep the dust down, I suggest you use Wax instead. It is far cheaper, compresses much better, and although the ping pong ball stuff is not likely to be very impact sensitive, the wax will be safer.

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This is my favorite slow burning fountain comp, and it's so easy to make. I sub the steel for titanium usually, but that's entirely up to you. It's easily hand mixed (screening isn't even required), and I like to boost its performance with whistle comp (if you so desire). I've made many large fountains with this formula, and they always get lots of compliments.

 

Potassium Nitrate 43.5

Charcoal 15.2

Sulfur 10.9

Metal particles, iron/steel/FeTi/Ti 30.4

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Hmmm Maybe i need to put one of them in my sweet corn on a trip wire.

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If you are using the NC to keep the dust down, I suggest you use Wax instead. It is far cheaper, compresses much better, and although the ping pong ball stuff is not likely to be very impact sensitive, the wax will be safer.

Just to make sure (i'm a french man, not that much vocabulary ), when you say wax, it is candle wax? Or another? If candle wax, what are you using to dissolve it?

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Sulfurstan, paraffin wax(candle wax) is soluble in toluene.
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Thanks. I ll try this kind of "binder" in my fountains, should also be good to protect the Al from the potassium nitrate...
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  • 1 year later...

Hello,

I'm searching the opposite-A powerful & fast BP composition that can lift or throw tiny mild steel granules to at least around 40-45meters.

In India we hand ram the composition in terracota(earthen & burnt) pots of different sizes.

Lot of other technicalities are involved, but I want to give a try.

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What you may want is a Clark"s Giant Fountain . I you look on you-Tube for it you should find some references on it...........Pat

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The fine detail of the Clarks fountain and the Asian Tubri is never mentioned sadly. The comp is simple it's fuel and oxidiser like a rocket the sparks are formed with charcoal and iron filings but the nature of the iron filings is important especially the carbon content and the oil that covers them! No-one bothers to write down what iron fillings they use, and that's the info you really need.

 

To be impressive these both need to contain a lot of powder You may make tests at 100grams but you make the competition item at much bigger weights maybe 5kilos of powder, and sometimes you need to scale up the particle sizes sometimes you don't. Just like a rocket you need a comp that's fast enough to throw the stars out but not fast enough to split the pot into shrapnel.

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The fine detail of the Clarks fountain and the Asian Tubri is never mentioned sadly. The comp is simple it's fuel and oxidiser like a rocket the sparks are formed with charcoal and iron filings but the nature of the iron filings is important especially the carbon content and the oil that covers them! No-one bothers to write down what iron fillings they use, and that's the info you really need.

 

To be impressive these both need to contain a lot of powder You may make tests at 100grams but you make the competition item at much bigger weights maybe 5kilos of powder, and sometimes you need to scale up the particle sizes sometimes you don't. Just like a rocket you need a comp that's fast enough to throw the stars out but not fast enough to split the pot into shrapnel.

 

 

 

Actually I've achieved a certain level in making said kind of fountain, but it's not up to my satisfaction level for which I'm not posting in forum. Neither I found option to post video of experiments just here(Don't have youtube link).

Not only the comp, but processing of the composition, fineness of metal particle+carbon content as well as quality+size of the pot and processing of the pot all are equally important here.

 

Will share if anyone is interested.

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The fine detail of the Clarks fountain and the Asian Tubri is never mentioned sadly. The comp is simple it's fuel and oxidiser like a rocket the sparks are formed with charcoal and iron filings but the nature of the iron filings is important especially the carbon content and the oil that covers them! No-one bothers to write down what iron fillings they use, and that's the info you really need.

 

To be impressive these both need to contain a lot of powder You may make tests at 100grams but you make the competition item at much bigger weights maybe 5kilos of powder, and sometimes you need to scale up the particle sizes sometimes you don't. Just like a rocket you need a comp that's fast enough to throw the stars out but not fast enough to split the pot into shrapnel.

 

Small scale tests don't really work in this case, or at least not with the Clark's Giant Steel Fountain. The case pressures are much different in the real deal than any smaller test.

 

Also, for what it's worth, The Chemistry of Powder and Explosives is fairly detailed about everything involving the Giant Steel Fountain.

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  • 2 months later...

"The fine detail of the Clark's fountain and the Asian tubri is never mentioned sadly."

With due respect Aurther, I'd like to state that Clark's fountain & Indian tubri is entirely a different entity. Please search with "Tubri Competition" in youtube & you"ll feel what I'm up to.

Indian tubri composition is compacted in an earthen pot which is somewhat fragile & challenge is to achieve great height & spread without even a crack-mark on the earthen pot.

And last part of your statement.

This is the topic which has been less discussed in this forum as per my search goes as compared to aerial fireworks. Acceptable reasons could be very less involvement of Indian pyros as compared.

Nevertless, though the BP composition is some kind of simple but a lot of technicalities are involved into this.

I'm making progress in this project & surely share my success with forum & put forth all details for interested people to the best of my knowledge.

Tubri is huge and great fun.

 

Regards,

SKC

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When ramming a fountain with micro stars or dragon eggs wouldn't the ramming process break the stars up and not produce the effect of a star shooting out or dragon egg making single pops you would think it would just crush the stars into powder and then the crushed star would just effect the color of the flame could someone please explain how this works

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It does not. The powdered fountain composition kind of cushions and surrounds the microstars. Some might get cracked or smashed, but the majority survive.

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  • 2 weeks later...
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