Making Whistle mix

[AdmiralDonSnider]

Surprisingly the search function didn´t vomit out useful results, so...

 

I´ve never made whistle mix so far and although I read through the information given by Öztap and Hardt, I´m still unsure about a few details concerning the "emulsion" you make:

 

- about how much solvent to use (viscosity of the slurry) when wetting the iron oxide, vaseline and benzoate

 

- about what Hardt refers to when he talks about "other suitable solvents" apart from toluene. Which other solvents will work?

 

Thanks!

[sparksnsky]

You can use lacquer thinner as well.

[FrankRizzo]

Ball mill your potassium perchlorate and the iron oxide together for 2hrs in an optimized mill, or longer if you have a slower rock tumbler or similar. Also, make sure that your benzoate is extremely fine and dry. If it's a coarser material, dry it in an oven @250F for a few hrs and ball mill it immediately after cooling.

 

Once you've done the prep work and your chemicals are both finely powdered and dry, screen both the fuel and oxidizer together (3) times through a 30-mesh screen. ***Do not scrape your fingernails against the screen or use a hard tool to force the material through*** Use only hand pressure and a shaking motion of the screen to pass the material. Add the screened mix to a large ziploc bag (note: 1kg fits nicely in a gallon size bag. Make sure to get the style with two zipper closures for extra strength and leak prevention). Pour in enough solvent (denatured alcohol, lacquer thinner, or E-85 gasoline) to wet the mix to a firm clay consistency. I typically use ~16oz of solvent for a 1kg batch...you may need more or less. Squeeze the air from the bag, seal, and kneed the solvent/vaseline mix through the bag until thoroughly wetted. Granulate through standard aluminum window screen and lay on newspaper to dry.

 

Instead of vaseline, I personally prefer to use 2% red gum with the same solvent and processing routine.

[AdmiralDonSnider]

Very helpful (although I try to avoid ball-milling). Thanks, Frank!

[Sambo]

I don't ball mill mine, i just separately de-clump through a 120# screen. Everything goes into a ss bowl then and is flooded with toluene/xylene paint thinners and mixed untill enough solvent has evaporated and it is like a soft clay like consistency. I then push it through the 120# screen twice and finally kneed and fold it with my hands. It sounds long winded but only takes about half hour to make a kg.

What are you looking to use it for anyway? I go through this process as I'm using mine for rockets, if your using it as a shell booster a single pass through the screen while wet should be enough.

I also don't use any vaseline or such.

[AdmiralDonSnider]

What are you looking to use it for anyway?

 

I simply want to make tubular whistles to be shot from mortars or as an added effect in bombettes, shells etc.

 

Thanks for your very useful input as well.

Edited September 18, 2009 by AdmiralDonSnider

[dagabu]

I agree, no ball milling of whistle comp, complete or other and no screening either.

 

I screen everything through a 200 mesh screen by itself (taking time to clean the screen between chems) and combine using the diaper method. I have nothing against baggies but when mixing up 500 grams of comp, 1" of distance nearly halves the brisiance of whistle if it ignites. In fact, 6" of open air will leave all fingers intact... Think about that for a moment.

 

I do use baby oil in my comp, Vaseline is messy and unnecessary. I use Acetone, very quick dry times.

 

Is this Benzoate whistle? Should have asked first...

[AdmiralDonSnider]

I agree, no ball milling of whistle comp, complete or other and no screening either.

 

I screen everything through a 200 mesh screen by itself (taking time to clean the screen between chems) and combine using the diaper method.

Is this Benzoate whistle? Should have asked first...

 

Concerning integration there´s no difference to the way I make flash (most people recommend to treat whistle mix like flash) and I will also choose the diaper method.

 

There is no need for a binder when it comes to whistle mix granulation, right? The solvent just wets it and evaporates (without dissolving any chemical?), and I can´t find any other binder in the formula.

 

I want to use chlorate-Na-benzoate whistle. I also have perc and salicylate, so...

[dagabu]

I use this recipe:

 

Potassium Perchlorate 70

Sodium Benzoate, -325 mesh 30

Iron(III) Oxide, red 5

Baby oil 1

 

All measurements in weight per parts not percentage

 

I am not sure of all the reasons that a wax or oil is used but if pressed dry, it will crack and CATO.

 

Dave

 

BTW- I have never seen any whistle comp with Red Gum and I have seen a lot!

Edited September 18, 2009 by dagabu

[Sambo]

I simply want to make tubular whistles to be shot from mortars or as an added effect in bombettes, shells etc.

 

Baring this in mind you might want to consider a slow whistle like 64/32/1 with 3 vaseline/mineral oil, I would also go with the benzoate(gives a better sound IMO). Black copper oxide gives a good raspy sound as does red iron oxide, oxychloride is aparently quieter.

I have used hot 76/23/1 whistle in inserts and ruptured the cake tubes, the pressure of lift and the whistle burning was just too much for the tubes to take. If I use fast whistle inserts now ill first press a small bp incriment before whistle, this solved my problem. Also a slower whistle will make a better sound than a fast one.

Ah shit, Ive just written this and now realised you're going to use chlorate. It should be a similar theory though with more fuel slowing the mix down.

 

Dagabu, I have pressed 70/30 whistle dry on some pusher tooling and haven't had any problems. I believe the waxyness of the benzoate helps bind together.

Also the iron oxide being a catalyst is only needed in small amounts, 5% is way too much. If it works for you though keep on doin' it.

[FrankRizzo]

If you do not ball mill the ingredients, or make positively sure they are ground fine as purchased from the supplier, you will not have a quality whistle mix. Simple as that. It may "work", but you're not getting nearly the potential that you could. Obviously, whistle mix should **never** be ball milled together. Even the old-timers that I know who had done this for many years previously (without incident) do not do it any longer.

 

Red gum as a whistle binder is a fairly new adaptation. I tried it after reading about Ned's experiments with binding BP ingredients with it. It works wonderfully, and is more storage-stable as the binder is less likely to migrate from the mixture into the walls of the paper tube as mineral oil (baby oil) or vaseline tend to do. I later learned that it was not an original thought when a few members of WPAG told me they had been using the same technique (RG binding) to make whistle burst granules for crossettes. The 2% figure was simply a direct adaptation of Ned's numbers from the BP testing he did. At that low of a percentage, it didn't adversely affect the burn-rate of the BP, but still achieved a nice binding action. I tried it, it worked for my uses, so I continue to use it.

 

Varying the ratio of iron oxide to perchlorate above ~1.5% will impact the tone of the whistle. 1.3-1.5% produces the optimum catalytic action. After that point, the only increase in burn rate is due to the lowering of the density of the mixture. Since the extra iron oxide is added at the expense of fuel/oxidizer, total evolved gas is lower, so the mixture will do less work.

[psyco_1322]

Don't use chlorate whistle if you have perchlorate laying around. Chlorate whistle not only only has the issues associated with chlorates but its also about as sensitive as strobe mix. Just make some normal whistle with perchlorate. Since they aren't rockets, I would just go with a slower, simpler 70:30 ratio. You don't really even need at catalyst. The benzoate is going to give you the best/loudest/raspiest sound, and its cheep, use that.

 

Red gum makes for a pretty stable fuel for long term storage or use in back weather like we had at the convention this year. Its a better fuel than oils or waxes obviously, so its going to allow the fuel to burn a bit faster than "normal" fuel with Vaseline or oil in it. It also makes the fuel a tad more sensitive since its not soaked it petrol products. Still its better than whistle made with chlorate.

[dagabu]

Baring this in mind you might want to consider a slow whistle like 64/32/1 with 3 vaseline/mineral oil, I would also go with the benzoate(gives a better sound IMO). Black copper oxide gives a good raspy sound as does red iron oxide, oxychloride is aparently quieter.

I have used hot 76/23/1 whistle in inserts and ruptured the cake tubes, the pressure of lift and the whistle burning was just too much for the tubes to take. If I use fast whistle inserts now ill first press a small bp incriment before whistle, this solved my problem. Also a slower whistle will make a better sound than a fast one.

Ah shit, Ive just written this and now realised you're going to use chlorate. It should be a similar theory though with more fuel slowing the mix down.

 

Dagabu, I have pressed 70/30 whistle dry on some pusher tooling and haven't had any problems. I believe the waxyness of the benzoate helps bind together.

Also the iron oxide being a catalyst is only needed in small amounts, 5% is way too much. If it works for you though keep on doin' it.

 

Lots to respond to:

 

I use Benz because I get it for a good price and IMO, it has a better sound.

 

The recipe is Dr. John Stienbergs from the PGI. I got the two numbers switched...

 

Iron(III) Oxide, red 1

Baby oil 5

 

Thanks for pointing that out, OOPS!

 

I have had heaps of problems with 70/30 whistle as it wants to CATO all of the time and I almost quit making them all together. I just happened to be fusing one and a fellow guild member noticed that I was J hooking my fuse like I do with my BP rockets and he asked me if I got a lot of CATOs. "Yes." I responded, "Well, you know that if you have ANY back pressure on the core it will deflagrate and not burn."

 

Needless to say, I changed all of my fusing to either side fusing or touch fusing with slurry. I also found as you did that you have to press BP as the first increment if you want inserts to work properly. If the whistle lights in the cake/can/shell, its boom time.

 

I'll have to try the dry press again, perhaps it was too much pressure, that can cause a case to accordion which straightens when burning causing craks... BOOM!

 

Dave

[Sambo]

I'm unsure of the pressure I pressed the dry whistles at, it was enough to solidly consolidate the grain but I believe it was lower than the standard loading pressure.

 

If you do not ball mill the ingredients, or make positively sure they are ground fine as purchased from the supplier, you will not have a quality whistle mix. Simple as that. It may "work", but you're not getting nearly the potential that you could.

 

The same could be said for your whistle, coarse screening 3 times and wet mixing in a bag isn't that thorough. Many people swear by screening it wet several times before ricing it. Maby my extra screening and kneeding compensates for the slightly coarse benzoate, the resulting wet mixture has no gritty feeling at all, it feels like soft plastecine.

 

I tried to ball mill benzoate once and ended up with a clogged up mill jar, ill never do that again. A coffee grinder works better and gets it to a usable fine-ish powder.

[WonderBoy]

I've always dissolved vasoline with VM&P Naptha. I saw that no one had mentioned it yet, so I just thought I'd add it to the list of solvents.

[FrankRizzo]

I'm unsure of the pressure I pressed the dry whistles at, it was enough to solidly consolidate the grain but I believe it was lower than the standard loading pressure.

 

 

 

The same could be said for your whistle, coarse screening 3 times and wet mixing in a bag isn't that thorough. Many people swear by screening it wet several times before ricing it. Maby my extra screening and kneeding compensates for the slightly coarse benzoate, the resulting wet mixture has no gritty feeling at all, it feels like soft plastecine.

 

I tried to ball mill benzoate once and ended up with a clogged up mill jar, ill never do that again. A coffee grinder works better and gets it to a usable fine-ish powder.

 

Wet mixing in a bag is not thorough enough, it simply serves to distribute the solvated binder throughout the mixture. Screening achieves a level of intimacy that cannot be achieved by kneeding. Again, if you're looking to get the absolute best performance from your fuel, you screen the ingredients together. This is true of *ALL* compositions.

 

On ball milling benzoate. Notice that I said to ****DRY**** it in the oven before attempting to mill it. Your mill jar and media ****ALSO**** need to be ****DRY****. It works, I do it regularly.

 

Coffee milling the benzoate will never give you a fine enough product. Granted, mix made with it will whistle, and a rocket will leave the launch tube, but don't expect to be able to use it to make a strobe rocket or lift a decent sized shell.

[dagabu]

Wet mixing in a bag is not thorough enough, it simply serves to distribute the solvated binder throughout the mixture. Screening achieves a level of intimacy that cannot be achieved by kneeding. Again, if you're looking to get the absolute best performance from your fuel, you screen the ingredients together. This is true of *ALL* compositions.

 

On ball milling benzoate. Notice that I said to ****DRY**** it in the oven before attempting to mill it. Your mill jar and media ****ALSO**** need to be ****DRY****. It works, I do it regularly.

 

Coffee milling the benzoate will never give you a fine enough product. Granted, mix made with it will whistle, and a rocket will leave the launch tube, but don't expect to be able to use it to make a strobe rocket or lift a decent sized shell.

 

Yup, Franks right, dry your benz and your ball mill. Works fast too. Only and hour in the mill and it will almost all pass through a 200 mesh screen. A blade type grinder works great too but constant screening is necessary for the right mix.

[AdmiralDonSnider]

" The mesh size of the component materials is important (...): the smaller the particles, the greater the thrust and the better the sound quality. The author uses ballmilled 170-200 mesh composition, which doubles the effect of the commercial 120 mesh material." (Öztap in Pyrotechnica XI)

 

I guess Frank is right in what he says about performance. However, I still consider it tedious to - probably - mill both separately, the perc with Fe2O3 and the benzoate, unless you are using multiple jars or jars reserved for this purpose only. Moreover people who are regularly using their mill to make BP or streamers will not go through the cleaning process twice.

 

I guess many amateurs will be satisfied if they reach commercial whistles in performance. As far as I know commercial makers try to avoid milling processes wherever possible and tend to rely on fine raw materials. Thus, if Öztap doubles the effect compared to commercial when working with material of 170-200 mesh, this will be whistling enough - at least for me personally.

 

Benzoates tend to come extremely fine; with potassium chlorate or perchlorate the same is true, but these materials tend to clump (but are fine again when broken up). So I guess if you use prescreened materials - probably also ground separately in coffee grinders - and integrate those by screening, you will get commercial performance (not an ideal one).

[dagabu]

Benzoates tend to come extremely fine

 

Not mine, its all in 1/8" x 1/32" needles. Breaks really easy and is easy to ballmill too. I have four jars and one is dedicated to each of the types of chems that cant be cross mixed.

 

Dave

[AdmiralDonSnider]

Yes, with this access to machinery it will be easy to mill it.

 

I´m sure there will be more questions coming up when I´m actually preparing the mix. Meanwhile, thanks everyone for the really interesting and helpful thoughts. Glad to be here...