Supplies:

In addition to the usual stuff (mallet, tube block, clay and grog mix, dowel, tube, etc) you will need the following:

A pan, newspaper, and the things I remembered to take pictures of:

			Toluene - You will need a solvent for the oil/Vaseline. Toluene works well, but lacquer thinner supposedly works also. Be careful, toluene is very flammable!
			Screens - You are going to need a window screen (around 20 mesh) for granulating the finished compo, and a 100 mesh screen to make sure that your particles are fine enough.
			Paraffin Oil - Or Vaseline. Paraffin oil is mineral oil. Supposedly this is a phlegmatizer, but I have heard argument that it serves a greater purpose.
			Bowl - You will need a good mixing bowl. I used this bowl because it is tacky and deserves to be used to mix chemicals. A bigger bowl will make your life easier.
			NaC7H5O2 - The formula I am using uses sodium benzoate. This will need to be screened to at least 100 mesh. A particle size any bigger WILL NOT WORK!! I use a wooden dowel to make sure the mix falls through the screen.
			KClO4 and Fe2O3 - Potassium Perchlorate and Red Iron Oxide also need to be screened through a fine screen. 100 mesh should be sufficient.

Manufacture:

The formula for the whistle mix that I am using is as follows:

(by weight meatball)

70% KClO₄

30% NaC₇H₅O₂

+3% Paraffin oil or Vaseline

+1% Fe₂O₃

			First screen the materials. Make sure that the iron oxide and potassium perchlorate are homogenous. Make sure you keep the fuel and oxidizer separate for now, you will be mixing them later.
			Make sure you wear a good respirator, the next steps involve working with a solvent. Please note that toluene dissolves these latex gloves that I am wearing in the picture. Consult the safety section for information about the respirators I use.
			Mix the oil/Vaseline with the toluene and store it in a flask. Don't use an excessive amount of toluene, just enough to evenly spread around the mix but not over saturate it. Do this outside or in a well ventilated area. Make sure you weight and use as much oil as specified in the above formula. You may wish to weigh a slight excess to ensure a 3% transfer to the mix.
			Now that you have moved outside, pour the fuel (NaC7H5O2) into the bowl that you are using. It is a good idea to wear your respirator when you are tossing around finely powdered chemicals.
			Pour the toluene/oil (or toluene/Vaseline) mix into the fuel. Make sure you use the whole bottle,
			Mix all of that up with a wooden dowel until it looks like the picture. Tijana thought it looked very tasty. I offered her a spoonful and she declined.
			Now it is safe to pour the oxidizer/catalyst into the bowl.
			Get ready...
			Stir! Pour more toluene into the mix as needed. You want to get it soupy. Don't worry about using excess because this stuff dries fast.
			When the mixture is super homogenous, it should look like this. Make sure you mix it really good, this mix needs to be mixed very well or it will not work.
			Pour the slop onto an aluminum (or similar) tray. Don't use plastic, the toluene will eat into the plastic and after everything is dry the mix will be dissolved into the plastic.
			Spread it out evenly so that it dries faster. It should only take 10-30 minutes or so to dry if you live in a dry climate like I do.
			Break the mix up into chunks and set them on a screen. You will want to push them through the screen to granulate the powder. The granules will probably turn into a somewhat fine powder, this is normal.
			Spread it out thin to dry. In my climate it takes a very short amount of time to dry. When the smell of toluene is gone the mix is ready. It will not take days to dry, maybe overnight, but not days.
			Now it's time to make the whistle. Select a nice tube (the wider the louder). The ID of the tube does not affect the note, the frequency is caused by oscillating gases. Insert the tube into your tube block and pour some clay into it. You won't need much, just enough to seal the bottom and support pressing the whistle mix.
			Ram the clay real good. You can put away your rammer after your done with this step because you won't need it when consolidating the whistle mix.
			Select a portion of whistle mix. Make sure the smell of the solvent is completely gone.
			Pour a small section of powder into the tube. Start small, you can experiment with bigger sections later. I recommend starting at 1/2 the ID of the tube.
			Hand press the powder in the tube. Repeat this and the previous step until there is enough powder in the tube. You'll want to leave around 1/3 of the tube empty after the mix is pressed in.
			Now put the last bit of powder in the tube and insert a fuse.
			Use a dowel with a line grinded down on the side (big enough for the fuse). Hand press this so that the fuse is stuck into the composition.

Here is the finished product glued down to a piece of cardboard to hold it in place when burning. If you don't put a base on the whistle will fly all over the place.

You can use this mix to make whistle rockets as well. You will might want to use a core with these rockets and you don't need a nozzle. Whistle mix makes great shell burst powder as well.

Troubleshooting:

My whistle explodes! - Sounds like the composition isn't consolidated enough. Whistles will explode if the powder is too loose. The will also explode if there are cracks in the composition.

My whistle is hissing at me! - If the components to your composition aren't fine enough the whistle will not whistle, it will hiss. Remember, at least 100 mesh or it will not work. 80 might work, but that's pushing it. 60 will definitely not work.

My whistle doesn't work and burns with a slow moving flame! - Sounds like it isn't dry yet. If a flame like that from a campfire is present, it's probably the toluene burning.

My whistle rockets don't work - Replacing the Sodium Benzoate with Sodium Salicylate (1 for 1) will speed up the compo and increase the rocket lift.

I've followed all the instructions, but I live in a humid environment and my whistle mix won't work - Replace the Sodium Benzoate with Potassium Benzoate and your mix will resist humidity.

What can go wrong - Deliberate dud, check out the test shoots section for details. Download the quicktime version.

When it goes right - A small working whistle, check out the test shoots section for details. Download the quicktime version.