114 replies to this topic

[yanhua]

Hello there

Has anyone sucessfully made any coloured strobe compositions, specifically blue, red, green, yellow and purple.

If so, I'd be interested to see any formula used.

Thanks

Yanhua

[Aussie Pyro King]

Yes go to http://huizen.dds.nl....html#chapter10 and look under stobe stars. I find that the blue ones are very good. Hope it helped.

Jared

[Steve]

Does anyone know any that don't require ammonium perchlorate? I've only managed to find a white one using BaNO3 as the oxidizer.


Steve

[BigG]

Bleser has quite a few good one that do not use AP. They work fine - although I have seen better:

Green:
Barium Nitrate 53
Sulfur 17
Hexachlorobenzene 13
Magnalium 100 mesh 12
Dextrin 5

White:
Barium Nitrate 51
Sulfur 19
Magnalium 100 mesh 18
Potassium Nitrate 7
Dextrin 5

Hexachlorobenzene has been a popular chlorine donor in the states. Not much in Europe. I can't see why you would not be able to replace it with other chlorine donor, achieving only slightly different results.

[Steve]

Thats the white i use, i forgot about the green, i'll try it agian seeing i have parlon and saran to use now.

Cheers

Steve

[Yugen-biki]

Some weeks ago I found a page on the net dealing with a blue strobe rocket (can?t find it now ). I recall myself reading something about a modified blue strobe formula for use in rockets. (End burning?).
My id?: Is it possible to use another stobe formula (like the white one!) and have it as a propellant? On the condition you don?t ram it, use a "safe formula" and make it burn slower. Has enyone eny experience of this, or is it to dangerous?

The effect would be so good looking useing some white comp.

Fsssss....fop fop fop fop fop fop kabush!

[BigG]

Some weeks ago I found a page on the net dealing with a blue strobe rocket (can?t find it now ). I recall myself reading something about a modified blue strobe formula for use in rockets. (End burning?).
My id?: Is it possible to use another stobe formula (like the white one!) and have it as a propellant? On the condition you don?t ram it, use a "safe formula" and make it burn slower. Has enyone eny experience of this, or is it to dangerous?

The effect would be so good looking useing some white comp.

Fsssss....fop fop fop fop fop fop kabush!

I wanted to avoid this – but I see nobody else want to take it on – so here is your blue strobe formula – from Bill ‘The Doc’ Barr Video.

63% Ammonium perchlorate, ball milled to a fine dust
10% Copper oxide (black copper oxide, CuO)
5% PVC powder
22% GE II Silicone #5000 (bathroom caulk)


It is known that a brilliant blue strobe (or just brilliant blue stars) is in the realm of dreams for most but the commercial manufacturer. Try to think about blue stars you see. They are usually very “dark”. The reason is that CuO decompose at relevantly low temperature – so any blue has to use “cold” fuel. This is why lactose is very commonly used in such formulas. Add hot fuel such as magnesium or magnalium and the CuO will decompose too quickly retaining a white flame rather then a blue one. Commercial manufacturer seem to be able to control the temperature of the flame better and manufacture compositions that are close to optimal decomposition rate.

Bill Barr chooses some very unusual component in his formula, and the reasons for that are in his video. While such formulas are not in the realm of HE (the composition burn very slow actually), the inclusion of Silicon increases sensitivity considerably. Such a mixture will have to be pressed. You can’t ram it. Also, there are many type of bathroom caulk, and Bill specifically warns against using anything else then the one specified in the formula. Most likely it wont work, and in addition, some bathroom caulk contain materials that are very incompatible with ammonium or copper.

Using strobe formulas as fuel is most visible, and there are some good videos from American firework news on how to construct them. All I can say that your traditional designed are most likely to fail as such fuel is very hot and the engine blows up in mid flight. Even thick tube is prawn to this problem. Consistency and pressing pressure are very important to get the effect perfectly.

Hope this helps. BigG

Edited by BigG, 29 January 2004 - 03:42 PM.

[BurlHorse]

BigG,

Docs Formula is really hot, and very friction/shock sensitive. I like the "Putters" or "Farters" as we call them (Strobe rockets) and have made a few. This comp is quite "Springy" so if your going to fill a casing and want to leave say, an inch of free space for a heading, or clayplug to be drilled through (BY HAND) to passfire to a heading, press to about 1 and 3 quarters inches below end of casing, to allow the comp to relax after pressing. Doc also reccomends using or should I say dedicating a set of tooling for these as the tooling will become quite messy. This comp is extremely flammable even in it's "Wet" state so anyone trying it, stick with small batches at first just enough to fill a casing or 2, use a blast shield when pressing etc.

FYI, when cured this stuff really takes fire easily and is suitable for making cut stars, the method being to build a small (Basswood or even balsa wood will do) 1/2" by 5" x5" frame, line it with cellephane, I tried Glad wrap/Saran Wrap but the comp stuck to it, cellophane works well though. Anyway, mix your comp and squeeze it out onto the cello lined frame, level it as best you can, it's incredibly messy stuff and let cure for 1 week, using a sharp knife, scissors will also work, cut the 5x5 into 10 strips length wise, then cut those down to 1/2 by 1/2, voila, 100 Blue strobe stars! My burn time for 1/2 by 1/2 stars is about 1 mississipi, 2 mississipi, 3 missi...consumed. in the star form they don't truly "Strobe as in a real on and off, but more of a low freq flutter, they make an interesting flub, flub kinda noise as they burn too. I attempted to use Velienes prime for them but the effort of making it stick vs. blind stars was really probably not worth the effort as they take fire so easily.

Something I just thought of, Instead of the frame, users might try loading the still "wet" comp into a caulking gun tube, and cutting the tip off to about 1/2" opening and laying out lines of the comp on the cellophane, let that cure for a few days then cutting them into 1/2" pieces, just a thought. the added surface area of the caulk gun lines of comp should allow them to cure a bit faster ??

As always, safety is the key when working with all energetic materials, Gloves, face mask or at least goggles should be considered mandatory and this stuff stinks to high heaven, so work only in a well ventilated area or outside. Your results may vary by your own practices and methods, but BigG listed the best way, and the AP does have to be milled to dust.......

Regards, stay green,

Bear

[BurlHorse]

Interesting Formula, from Pyrotechnica XIII, developed by Peter Budarick for the Knox Pyro Ballet, display fired November 19th, 1988.

Electric Pulsar and fluttering white fireball formula - a sort of strobe, but very cool to watch them in action!

Ammonium Perchlorate------------------48.5%
Barium Sulfate----------------------------12.5%
Magnalium 125um dust-------------------20.5%
Alloprene 60 Mesh Dust (I used Parlon)--9.0%
Potassium Dichromate (Bad Stuff)--------4.5%
Budarick used vinyl wallpaper paste for his binder, I have tried both Starpol and dextrin, the latter giving best results------5.0%
Budarick used +12% water to bind, I rolled them so I don't know what the exact percentage was, 25/75 Alc/h20 to roll

My notes: Buy Pyrotechnica XIII, it also has the Crackling Microstars by Shimizu Study, Excellent reading.

Grind or mill Potassium Dichromate as fine as possible, it is used here to protect the Magnalium and as a burn rate catalyst to the formula: after milling, combine with magnalium and mix, (be careful Dichromate is an oxidizer as well as a known poison/carcinogen. Filter type respirator is essential and Pot. Dichromate is absorbed through the skin and mucous membranes, so where gloves, respirator and longsleeved cotton clothing, it also stains everything it touches Orange/Brown Be aware of what you are working with..... ) set MG/AL Pot Dic. aside for now in a closed container. Screen and mix Barium Sulfate ( Also absorbable through the skin), Dextrin, parlon until you have no visibly grossly seperate particles. Add Pot.Dic./MG/AL to this and mix/screen/seive well. Mill AP to the finest dust you can get, My Coffee Grinder (The one Marked Oxidizers ONLY) worked wonders for this step, re-weigh what you get out of the mill and grind a bit more since some will always stick to the inside of the mill. Finally add the AP to the rest of the mix and combine thoroughly.

I generally use #8 steel shot for most cores, but I used Molecular seives for these, pre-wetted for several days in a 50/50 Alc/water mix. You don't need many of these to start (Your starting off with a small batch anyway RIGHT ?) a level tablespoon holds about 250 of these cores. Anyway, use what ever core you feel most comfortable with if your going to roll these.

I did not try cutting them so I can be of no help there, however Peter Budaricks + 12% water sounds "About" right, probably a little too wet, but hey it will dry right?
It's always a good practice to reserve about 15% of your dry comp to add if you over wet the batch.

I rolled these up to 3/8ths of an inch with 25/75 Alc/H2o and let them dry for a week in a warm place, no direct sun, but anywhere the temperature is around 67 to 75 degrees will speed things along, I then rolled them up to a tad under 3/4" and a tad bigger than 5/8ths inchs. just the way they averaged. anyway, this turned out to be the perfect size for 6" ball shells. I don't have notes on weather I primed them or not, but any AP compatible prime should be fine.

Since the stars are so big and there is not alot of room for burst in a six with that size stars, You'll have to beef up the burst a bit. I used....Looking in my notes...... Ah, Bp Hulls, added whistle mix to the hulls, 4 parts hulls, one part whistle mix ratio with a flash bag containing 6 grams of 70/30 flash. I also separated the burst from the stars with one layer white gift wrap Tissue, Don't remember why I did it, but it's here in my notebook so I'm passing it along.

When the shell breaks, the stars are an intense white fluttering effect and leave a very visible white smoke poof with each flutter, very cool!!

Have fun with this, Be careful and follow directions, these stars are hot burners but not unruly or overly sensitive, even so, treat them and all comps with respect, use static guard spray on your working attire and remember if it's cold and dry the conditions for static discharge is multplied.

Regards, Stay green

Bear

[Yugen-biki]

Some interesting reading you guyes have posted! :-) I have never made any strobe formula and don?t know if it is a good id? due to sensitivity and expensive chemicals.
Is it possible to use something other then "bathroom caulk"? Parafine/stearin... spelling?

[BigG]

Some interesting reading you guyes have posted! :-) I have never made any strobe formula and don?t know if it is a good id? due to sensitivity and expensive chemicals.
Is it possible to use something other then "bathroom caulk"? Parafine/stearin... spelling?

Really no. I have no idea how the doc come about to use bathroom caulk. He is also very specific that other brands will probably not work. I can’t remember what that specific bathroom caulk contained, but I can imagine the doc sitting in the bath, after getting all sweaty from fixing that chip on the left side, having a hot dog in one hand the silicon tube in the other – reading through the list of ingredients that make the material – and suddenly shouts “Eureka!!!” – jumping out of the bath and running out to the workshop – chased by his wife with a towel and a plate (for the hot dog).

Must have been a day to remember.

Apologies to Bill - I heard he is a great guy

[Yugen-biki]

Ha ha ha!


Here is wath I think:
The silicone is the fuel in the "blue strobe formula". Strobe formulas are to "powerfull" to be used in rockets unless the burning speed is slowed down. There is no metal fuel like MgAl or Mg in the rocket fuel to reduce the heet and rapid pulsating gas developement. Instead of metal silicone is used. Why GE II Silicone #5000? It has the properties we are looking for. The formula becomes sensitive when the silicone is added. Some ingredient in the #5000 burns fast when combined with Ammonium perchlorate. Another ingredient in the #5000 burns slower making a paus in the micro explosins, but still producing gas. This is how whistle and stobe formulas work. The #5000 may be replaced but I am no chemisty expert (yet ) so I don?t know what will be good for this.

Or maby I am totaly wrong and just talking crazy

/John

[adamw]

Here is another one:

Winokur Green Strobe

Barium Nitrate 49
Sulphur 18
MgAl granular 60 mesh 11
MgAl granular 200 mesh 9
Hexachloroethane 6
Dextrin 5
Potassium Dichromate 2
Boric Acid 0.5

Winokur White Strobe

Barium Nitrate 53
Sulphur 23
MgAl granular 60 mesh 12
MgAl granular 200 mesh 6
Dextrin 5
Potassium Dichromate 2
Boric Acid 0.5


Pot. dichromate is suspected as being a carcinogen, so always wear PPE when handling.

[adamw]

Just lit a small sample from a batch of Bleser White strobe. Promising. The comp was very slightly damp with solvent (substituted dextrin with 7 parts shellac) and gave about 3 strong slightly green flashes from a piece about the size of a biro pen nib (yes an interesting comparison) at about 2.5-3 Hz. Have made some 15mm pumped stars with it, so I'll put them into use soon. Will let you all know.

[chim-chim]

Just lit a small sample from a batch of Bleser White strobe. Promising. The comp was very slightly damp with solvent (substituted dextrin with 7 parts shellac) and gave about 3 strong slightly green flashes from a piece about the size of a biro pen nib (yes an interesting comparison) at about 2.5-3 Hz. Have made some 15mm pumped stars with it, so I'll put them into use soon. Will let you all know.

You never let us know so I had to try myself,
this formula correct?

from Bleser[13], page 22. Listed as "formulation #26; white strobe"
Barium nitrate....................................51
Sulfur............................................19
Magnalium, 100 Mesh...............................18
Potassium nitrate.................................7
Dextrin...........................................5


I stayed with the dextrin though.
Only as far as your post so far, damp comp., nib sized pile, 2-3 impressive flashes, filled 3 - 3/4' tube plug/cups and will try them soon.

But I will really let you all know.