40 replies to this topic

[italteen3]

I did do numerous searches on the subject and a half hour with no success. So here I go.

Ordered my first ball mill (dual ball mill from harbor freight tools) potassium nitrate, some iron, firefly aluminum, and sodium benzoate. I already have some German Dark, Potassium Perchlorate, Dextrin, Sulfur, and some airfloat charcoal. I will be making mostly fountains, or as you Brits like to call them gerbs, mines, rockets, and some small cakes.

Im sure all of you have heard of the cake called saturn missile. For those of you who havent or if it is called something different by you it is just a bunch of whistling bottle rockets in cake fashion. I want to make a scaled up version of that for Independence day. Only thing is I am unsure as to how it is done exactly.

I have a general idea on how I will do it and made some of my own tools for now. Homemade tooling. The tube in the image is a 3/4" ID 1" OD 2 1/2" length. I went to home depot yesterday and bought a 48" length of 3/4" dowel rod. I cut to 1" pieces to serve as a gap for the flash and a wooden pressing rod to make the whistle and thrust. Im beginning into pyro so I am unsure as to whether the tube is long enough or how long the whistle mix should be in order to lift the tube and the payload. I do know not to ram whistle mix, just a gentle press by hand.

My two concerns are how long should the engine be? Lastly will the whistle mix at the end of its thrust and whistle ignite the flash payload to complete the big saturn missile? If not how can I do this?


One last thing the sodium benzoate should not be a problem with the flash now should it, didnt find anything through any searches but feel free to correct me.

Thankyou!

[alany]

You should really use a press for a 3/4" rocket, the largest I've ever hand-pressed is 1/2" and it didn't work very well. Personally I'd start with something a little smaller for your first whistle rocket. 3/8" is good, and can be pressed by hand quite easily.

If a whistle blows the result is devestating, whistle composition has enormous energy density.

I recommend a clay plug above the propellant grain before the flash. It gives more predictable timing of the terminating effect, it also makes the motor stronger mechanically. It is more critical for larger motors, bottle rocket scale ones are fine to just to use a nipple to create a little space for some flash then close the top with a paper plug and/or hot-melt glue.

Whistle will ignite flash just fine, and flash in contact with whistle is fine too. In fact loose whistle works just fine for a report too, but it isn't bright like flash is.

The tube might be a bit short, I'd use at least 5" for a 3/4" whistle, probably longer. A shorter motor may still work just fine but the burn will be short and the payload will blow low. Remember that you need about half the tube empty or a long core for a nice loud whistle, and also if you intend to make them stickless by adding a nose weight.

[BigG]

the traditional size for 3/4id is 7.5 inch in length - and forget about "hand - press", you are looking at 8800PSI for this thing not to blow. Any praticliur reason why you are starting with whistel mix for fuel? How about starting with bp?

[italteen3]

I will not be starting in whistle mix solely. Sorry if it came off as that. It will just be one of my projects and main interests in the near future. Of the four books and a video I have, no information whatsoever on whistle, which is why I have not yet started whistle mix.

Thanks a lot alany and bigG for the advice, now ofcourse I have a good amount of questions .

I will be getting a press shortly so I will definately wait for that to come as well as a blast shield. It will be the small press from hobbyfireworks. I have goggles, latex gloves, respirator, and ear plugs for when working with whistle in the future.

I guess a nose made from kraft hot glued on should make for a nice lightweight nose. Audience will be seated far away so stray "missiles" are not a concern just a good serpent type effect. Would kraft, 7 or 8 turns make for a good little mortar?

Is that long of a length tube necessary for a 3/4" whistle? It just seems a bit large, but in the near future I will experiment.

Lastly if a clay plug is utilized will a short piece of blackmatch be fine for a delay to flash?

Thanks again guys!

[alany]

It is just a fact of the physics of whistles that they generally need to be much longer than they are wide, and the vanilla 10 IDs long BP rocket tube works well in whistle rocket service.

You don't need blackmatch to passfire from the whistle to the flash, but it can't hurt either. Just a hole in the clay will let gasses from the rocket end of things into the flash compartment and ignite it, but the blackmatch offers more reliability. I wouldn't bother with blackmatch myself, I'd just make a small impression in the whistle at the bottom of the plug penetration so there will be some whistle remaining to ensure a good blast of fire into the flash before complete burn-out.

I am not sure what you mean about the mortar? Unless what you want to make whistle spoulettes for a whistle to report bombettes used in a conventional cake? That's actually much easier, as the whistles need not be as large and need not produce any significant thrust.

Note that a good 3/4" whistle is *loud*! Fantastically so, in fact, we are talking about hearing damaging SPLs so be sure to be careful. Also, a 3/4" whistle motor is very powerful and quite capable of penetrating objects that get in its path.

[BurlHorse]

Hats off to you both, BigG and AlanY, good advice, and the dynamics of the tube length is important if you want it to whistle at all.

Italiteen, Since you already have the dowel rods, why not make a jig....glue dowel down to piece of wood, drill 1/8" hole in dowel 1/4" deep. With me so far? Get some fast visco, not vannila green stuff but the fast stuff, I suppose one strand of black match would work, but the quick vis will be hardier, now, place 3/4" piece of Visco in hole drilled in dowel, place tube over dowel with visco in place. Gently slide your ramming dowel down the tube until you feel the resistance of the top of the visco, Mark your Rammer at the top of the tube, go all the way around with a sharpie.

Now experiment a bit with the proper amount of Clay/Bentonite/cat litter etc until you can ram it solid without bending the visco. Once you have documented the proper increment, well in this case it is a one time affair, but an increment none the less....after Ramming or pressing, you should have a clay plug in the top of the tube, with the length determined by how long you made the dowel for the visco to rest in. I digrees, sorry.

Anyway, after it is rammed or preferably pressed and you remove the tube, from the long open end you will see 1/4" Piece of Visco sticking out of the clay, you will see only clay looking in from what is the payload section. Next, using an Awl/Icepick/Nail etc, scratch away at the clay in the very center, just enough to expose the visco from that end. There's your "surefire Passfire".

The rest is up to you, But I agree that Whistle is pretty potent stuff, apple for apple, nearly as strong as medium flash, Be Careful, Start Small as Alany Said. 3/4" is a very powerful place to start, back off to at least 1/2", you'll save alot of comp this way too as well as not having to mix large amounts for each device.

Those are my thoughts, Glad everyone else ponied up to help you too. Be sure and observe true safe distances, if it can fly up 150 ft, then it can surely skitter around a good 75 ft, and Your Friends can quickly become not so friendly after 10 or 15 grams of flash in your heading goes BANG ten feet from them from an errant Missle.

The Saturn Missle Batterys are cheap, especially the little 25 shot ones, and easy enough to dissect, gently pull all the "Missles" out of the case, then take an exacto
Knife and Slice Down along each edge of the top and then down Each Corner, Fold Back the sides and you will see how it's works. As a side note at our club shoot this weekend a guy let loose 6, 750 Saturn missle each, battery cakes! I found it to be completely Absolutely Annoying, but thats just me, . It was a great Shoot!!

To the Admins, I have dissasembled alot of these to use the plastic missles for inserts in shells, It is a Relatively straight froward operation and in my opinion does not represent any more than normal safety Hazard. Once the "Missles" are slid out there is more of a chance of cutting yourself with the exacto than anything Pyro-accident related. If you guys feel he should not proceed please feel free to edit out that part of the post.

Regards,

STAY GREEN,

Bear

[bobconan]

Whistle is some pretty wily stuff. I had a jumbo whistler rocket once 1/2 in od and it had gotten wet. i lit it anyway. im guessing the dampness affected tightness of the powder. It went off like an m80. Change of pants for that one.any whistler bigger then 3/8 is really loud. im pretty sure whistle will detonate in sufficient quanities. Any suggestions on mixing whistle. Pottasium Benzoate doesent seem to be to integration friendly. Im a big fan of screening.

Edited by bobconan, 19 May 2004 - 02:33 AM.

[italteen3]

Well I decided that I will start off with 3/8" whistles, pressed. It seems that where ever I go to purchase a ball mill manufacturer has it backordered. I have no time to build one or else it would have been built already, nor do I want to give up time building the mill over my lab and run it next to shed closer to house. So nothing until end of June except for whistles and booms which I am rather upset about. Sorry for babbling.....

Burl I get most of what you are saying. If you click there>http://italteen3.gam...le_ram_with_gap that is my mini quick homemade jig put together with some epoxy, quick work on armsaw, and too much hand sanding..... So basically on the dowels glued to the board I drill the recess for vis-quick and ram my clay plug over it. Now what I dont get is how to ram the clay plug without bending fuse? My thought was drilling a recess in the ramming dowel so the fuse can go in and ram around it, or is my lack of sleep making absolutely no sense out of this . Keep in mind I have never rammed anything yet.

The small 25 shot up to some of the more monstrous sizes use 1/4" whistles I believe. Increasing tube ID by 1/8" will make the whistle that much louder than the little weak thing I hear from the consumer fireworks? I would be very delighted .

Alany basically they will be a little 2-3 second whistle with a 1-2 gram flash payload, which is what I will be aiming for. The consumer cake which I believe is a 1/4" whistle goes up 50 feet, maximum, only in a few of the "missiles" did they achieve that height. So I am hoping for 75-125 feet average travel for a 1/2" whistle. A 1/2" whistle should have a tube length of atleast 4" correct?

Had a few close calls in my 16 years all do to plain ignorance and stupidity, boy have I learned. I may just start a thread about close calls....

Thanks alot guys for all of your help and advice!

[BigG]

Whistle is some pretty wily stuff. I had a jumbo whistler rocket once 1/2 in od and it had gotten wet. i lit it anyway. im guessing the dampness affected tightness of the powder. It went off like an m80.  Change of pants for that one.any whistler bigger then 3/8 is really loud. im pretty sure whistle will detonate in sufficient quanities. Any suggestions on mixing whistle. Pottasium Benzoate doesent seem to be to integration friendly. Im a big fan of screening.

Depend what type of whistle composition you use, but some whistle will detonate with as little as 5 grams when unconfined.

I have seen a ?whistle based? firecrackers. They were as loud as the flash one ? but required a few grams each rather then the customary 0.5g flash used in today?s firecrackers.

Would not suggest anyone to try and make them at home.

[Phoenix]

For setting fuses in plugs, I've always drilled a hole in the rammer as well as the jig. I use a long enough piece of fuse that it will prodrude through the loose clay before I ram it, so I can locate it it the hole in the rammer before proceding. This was using homemade cracker fuse, and as visco is rather stiffer and more robust that this, youy might not need to guide it into the hole in the rammer, and could probably just use a shorter bit, bury it in the clay, and allow it to find its own way into the hole when you rammed it.

On the other hand, I'm sure BurlHorse's method works perfectly well, and leaves more space in the payload sction (minimal protruding fuse) - but there seems to be a wider margin of error when loading the clay if a hole is drilled in the rammer, and it eliminates the scratching step.

BTW, BigG - if that's the USA, it's 0.05g isn't it?

[BigG]

5 miligram. you got me there

[bobconan]

approximating from memory the big whistlers are like 5/8 o.d. so ya probably a little bigger then 3/8. They were probably about 2-1/2 inches long.they easily break 100 Db Your ears do that loud noise response thing(u probaby have no clue what im talking about) and you can hear raspyness. Lighting only one i usually cant wait untill its done.But 30 or so? Give a nice report and youll probably have alot of people angry at you. Another question this one is about fountains tho. One time i bought these things called dixie whistlers and they were 4 different tones in one tube. How did they do that? Vary the tube dia or a different comp? You definetly have to pack those things tight or else you have a bunch of m80s flying at you. what ever you launching them out of I would make taller then the saturn missle batteries respectively, they are usually only the same length as the missles.

[chim-chim]

BTW, BigG - if that's the USA, it's 0.05g isn't it?

" ground firecrackers can only contain 50 milligrams of pyrotechnic content per cracker. (Aerial "reports," which are contained within aerial devices such as rockets and shells, can contain up to 129.6 milligrams of composition per report.)"


1000 mg to gram, so yes, .05g.


btw- a true M-80 contained about 2,916 milligrams, or just under 3 grams.
Since the Child Protection Act of 1966, crackers, maroons etc. have been rather meager

[adamw]

RE: Dixie's - Yes the different tones are created by varying the tube length. All to do with oscillation, standing waves and the such. Try it some time. Another way to vary the 'sound' of a whistle is to form it like a rocket, with a core. This will give a 'rasping' or 'screech' sound depending again on the tube length, size of core etc.

[pyrodude]

Do whistle mixes have to be pressed as i tried one the other day and didnt press it and it just burnt with a huge force but no whistle.