15 replies to this topic

[Draco_Americanus]

I cant seem to get my small rockets to whistle rockets to whistle, the thrust is fine but with
76 kclo4
23 sodium salicylate
1 red iron oxide
3 pertoleum jelly
(naphtha 25millileters]
these things book! they fly well but have no whistle? any ideas why?

[pudi.dk]

The perc and sali must be ball milled well, or else it won't work.
What do you press with?
I'd like to hear about your preparation of the whistle mix and the device though, it might help us help you

Edited by pudi.dk, 20 December 2007 - 10:58 AM.

[pyrotrev]

How small are your rockets?? I remember reading somewhere that benzoate/salicylate whistles only really work in tubes of bigger than 6mm diameter or so, and they need a space over the composition for best effect. Alternatively it could be problems with damp salicylate.

[will-TM]

How small are your rockets?? I remember reading somewhere that benzoate/salicylate whistles only really work in tubes of bigger than 6mm diameter or so, and they need a space over the composition for best effect. Alternatively it could be problems with damp salicylate.

I am pretty sure all whistling rockets need to have the tube only half full or so; so the sound vibrates off the wall and creates the whistling sound.

How would I go hand pressing 1/4" whistle rockets

[W.P]

I am pretty sure all whistling rockets need to have the tube only half full or so; so the sound vibrates off the wall and creates the whistling sound.

That's not a rule in stone, I've made whistles before with less than half an inch of empty space- they worked fine.

[seymour]

So long as the fuel is very fine, and preferably the perchlorate too the mix should whistle if dry. I have managed to get shrill whistles by even hand pressing Perc-Nabenz into 3mm ID tubes.

[will-TM]

Ok

I will be making perchlorate/benzoate whistles.

What formula would I use if I dont have naptha?

[W.P]

Just stick with 70:30 whistle mix, no need to be fancy about it.

[will-TM]

Ok thanks, just out of intrest why do people add binders and granulate ect.

More power?

[cooperman435]

Ive tried the plain 70:30 mix and now swear by the full vaseline and red iron oxide with solvent method. Its safer to make, produces a better result in use and as it slightly clumps when finnished is easier to hand press into rocket motors.

[Draco_Americanus]

The rocket tubes are about 9mm id and are 50mm long, i had been filling the whole tube with only a little spaceing at the end, i will try the 70/30 but i have had problems with them exploding when useing other ratios. I had been hand pressing them with a rubber mallet, i had tryed a larger one but had metal flake in the fuel. I used a hydroylic press for that one

[will-TM]

Leave a larger cavity for the sound to resonate, and try and get a vid

[Draco_Americanus]

I will try a larger cavity, as for the mix being damp, that i dont know, did not think that the salicylate was hydroscopic, the perchlorate is ballmilled and i will run the salicylate though the ballmill as well. getting video will be a problem. I dont know of anyplace to upload the video too and i dont have a working video camera but i think my digital camera will take a few seconds worth of video

[cplmac]

You can always upload to Pyrobin. I have noticed with whistle rockets that the length of the core has a great deal to do with how it whistles. The longer the core, the less it whistles. Maybe shorten that core up a bit, and try one with no core to make sure it's not your fuel.

[Draco_Americanus]

I whent with a 70/30 mix of fresh ball milled salicylate and left a longer cavity with no core and they whistled like a dream! the ones with a core failed to whistle so now it's time for new tooling and to see if they can carry a small report charge