shagaKahn Posted May 4, 2011 Posted May 4, 2011 Saw this on the toob: Though it flies like a stinger he calls it a "hummer." Claims the fuel is "Fe/Al C." Someone asks in the comments if he means iron oxide as the oxidizer but he doesn't respond. Assumed stingers/hummers were just a variation on the rammed BP theme, with an end burner and a side vent for stabilization. Do y'all use something besides BP for fuel in your hummers. The sound is surely delicious and way different from the standard whoosh of a BP burn.
Peret Posted May 4, 2011 Posted May 4, 2011 I don't see any evidence of titanium or aluminum in that fuel - nothing but charcoal. It looks like a Skylighter half-inch tube. If so, and if the pin on the left is representative, the nozzle is a bit too big for a stinger, so perhaps it was made on standard rocket tooling. I use standard (milled) rocket fuel for my stingers and for a half-inch, the nozzle is 5/32. They don't make a sound like that video and they take off a lot quicker. I happen to have a video - Stingers Hummers make more of a high pitched "whoop". Here's one I shot off in a 2 inch mine. Now I was a bit nervous of this mine so I gave it about an 8 inch visco leader, but when I lit it I realized I used FAST visco, so I was in a hurry to get away. There were two hummers in there (along with a bunch of whistles) but I only hear one of them take fire. This mine was a bit over-lifted anyway with 12g black powder, and the recoil cracked the wood base it was glued to. Hummers
Mumbles Posted May 4, 2011 Posted May 4, 2011 To really get hummers up to speed you can spike the BP with whistle. No idea if that would work on a hummer though. That looks to be just a BP based formula, maybe with some extra charcoal or maybe coarse C. It is a very lazy take off. It could probably be duplicated with unmilled comps.
shagaKahn Posted May 5, 2011 Author Posted May 5, 2011 But he says in the comments section that he used an "FeAl/C comp." Trying to account for what he must have used to get that amazing sound as nothing BP-based I've ever built sounds like that.
Blackthumb Posted May 5, 2011 Posted May 5, 2011 I don't make the stingers.....I just launched another BP/Sawdust rocket. 5/8 ID x 3" long....3/16 x 1 1/2" spindle. Used a clay plug-bulkhead and it worked great. These lift off very steady and build up velocity with a steady deep sound...unlike the straight BP or 6/3/1 fuel. My best guess is 500' plus...took about 7 seconds to return....Milled 'green mix' 6...cedar sawdust 1.......Setting up video this weekend.
Peret Posted May 5, 2011 Posted May 5, 2011 (edited) Trying to account for what he must have used to get that amazing sound as nothing BP-based I've ever built sounds like that. Maybe the blowout about half way through the flight is a clue to something. Edited May 5, 2011 by Peret
dagabu Posted May 5, 2011 Posted May 5, 2011 "You call that a Steenger? Now THIS is a Steenger! http://www.pyrobin.com/files/100_2183.jpg
shagaKahn Posted May 6, 2011 Author Posted May 6, 2011 Can't really tell what I'm looking at dag; is that multiple fuses? Wondering if it ain't the fuel so much as the spinning of the tube that's creating the sound that inspired this thread in the first place . . .
dagabu Posted May 6, 2011 Posted May 6, 2011 Can't really tell what I'm looking at dag; is that multiple fuses? Wondering if it ain't the fuel so much as the spinning of the tube that's creating the sound that inspired this thread in the first place . . . Tee-hee! Yes, I know, I did that on purpose It is a 1# Hybrid motor (pyro hybrid, no gasses) with two tangential holes spaced 180° apart and fused with fast paper fuse taped to a long section of visco. Its better to be a long way away from this sucker when it goes off! There is no fuse in the nozzle, the motor sits on a pin that it spins on. I launched a few last PGI, they all worked very well indeed. Yes, the Leslie speaker in older rock organs demonstrates the effect well. the Leslie speaker consists of two horns that spin around causing the sound to variate giving the impression of a much larger organ. the same thing happens with the hummer, the pitch increases as the nozzle approaches you and the pitch decreases as the nozzle runs past you. This variation in pitch is what is so attractive to us, the sound comes to us as a "hum". -dag
shagaKahn Posted May 7, 2011 Author Posted May 7, 2011 OK--but one thing I've not yet mentioned is that every stinger I've ever seen started out spinning on the launch nail but ended up flying up like a rocket. The device pictured in the video I linked to takes off and flies up like a helicopter. It's not just spinning; it's rotating. Is that because his side-hole angle is off a bit?
dagabu Posted May 7, 2011 Posted May 7, 2011 I am not sure of the nomenclature that we are using to differentiate between stingers and hummers, i have to read up on them first but I have made two kinds, those that only have two side holes for propulsion and those that have a bottom nozzle for vertical propulsion. This one looks like it only used the side vents and no bottom vent. -dag
shagaKahn Posted May 7, 2011 Author Posted May 7, 2011 Amen to that. He starts out calling it a stinger, then a hummer. My impression was that stingers don't hum and hummers don't fly--but this thing does both. And as said, it doesn't fly like a stinger; it rotates like a helicopter. Never heard a stinger sound like that--nor a hummer fly like that. Maybe it's a stummer...
Mumbles Posted May 8, 2011 Posted May 8, 2011 It sure looks like a stinger to me. It might just be a low powered one. As you said before it certainly doesn't take off like one. It could just be a different geometry than what is standard.
shagaKahn Posted May 8, 2011 Author Posted May 8, 2011 There are commercial devices out there that perform like stingers but require no launch board/nail. Anyone tried launching home-built stingers without the launch board? (Was referring to items like "Sound Colorful Bird" and "Sky Cruiser." Which reminds me of the original "Colourful Bird" from the 70's that for some reason has been banned).
shagaKahn Posted May 8, 2011 Author Posted May 8, 2011 Peret: "Hummers make more of a high pitched "whoop". Have played your vid till the kats are climbing the wall and still I can't resolve anything but the whistles and pops (and the wind). Does the hummer go off before or after the whistles? Thanx p,s
Peret Posted May 8, 2011 Posted May 8, 2011 Does the hummer go off before or after the whistles? Whistles first, then the siren sound of the hummer(s), then the reports.
shagaKahn Posted May 8, 2011 Author Posted May 8, 2011 Ah. That's pretty hot Peret; definitely gotta try'n replicate some hummers. First batch of stingers this afternoon--sans tooling. (Maybe that's how you make a stummer?).
Peret Posted May 8, 2011 Posted May 8, 2011 No tools needed for a hummer, except a rammer that fits the case and a drill for the side hole. I've made 3/8 inch, 1/2 inch and 3/4 inch and I like the half inch best. These are 1/2 inch inside, 1 inch long, with a 3/32 jet hole and fueled with milled 60:30:10. The one on the left has two jet holes on opposite sides. I found that one hole lights before the other so giving a kind of double sound, one delayed, and much less "urgent" than the single hole kind.
shagaKahn Posted May 8, 2011 Author Posted May 8, 2011 You got me; I'm inspired: hummers definitely next. But hey speak of no-tools-required, I've been researching stinger tooling and the drill-guides all seem a bit iffy to me. (Still gotta hand-hold it--and it ain't even a jig; you've gotta eyeball the space and hold it steady). It just looks imprecise and sloppy (for another 100-buk tool set). Will my no-tooling try really come out that much worse? Tempted to light one off right now in the yard--but sensibility says wait for a trip up to the high country. NightHawkInLight's got a pretty sweet end-burner stinger toot up on the toob and though the actual side-vent drill part is out of frame, he uses no tooling and his stinger sure takes off well.
Bilbobaker Posted May 9, 2011 Posted May 9, 2011 Maybe the blowout about half way through the flight is a clue to something. Did the walls fail on that?
zenen1 Posted August 11, 2011 Posted August 11, 2011 (edited) When a stinger is constructed the fuse or vent whole is drilled on an angle into the casing. When propellant is burned in the casing the vent whole produces directional thrust and causes the hummer to spin. Due to a generally high powered fuel when it is burned and the gasses escape through the vent whole a noise is produced, and as the hummer spins the vent whole turns away from the audience and back again thus changing the loudness of the sound heard and creating the sound that got these fantastic ground spinners their name, hummer. so technically if my theory is correct a stinger could fly while still producing the "hum" you would get from an ordinary hummer. That is just my two cents, if any part of this post is incorrect, please point out my flaws -zenen Edited August 12, 2011 by zenen1
dagabu Posted August 15, 2011 Posted August 15, 2011 Hummer, stinger, z-bomb. Anyone care to flesh out what the core differences are between all three? -dag
Mumbles Posted August 15, 2011 Posted August 15, 2011 A hummer is a shell insert. It has a single hole tangental to the wall in the center of the tube. A stinger is a spin-stabilized rocket. The tooling itself is not too different from strobe tooling or the older whistle tooling I've been told. There is a core and a nozzle. There is a hole drilled tangental to the wall just above the nozzle where the rocket is actually lit. It spins up to speed, and when it hits the core it takes off. They can definitely have a hum to them. A z-bomb is somewhat like a stinger. It's really hard to describe without pictures. Basically there are two angled tangental holes on the bottom which both lift and spin the tube. There is a tutorial on passfire if you're interested.
dagabu Posted August 16, 2011 Posted August 16, 2011 A hummer is a shell insert. It has a single hole tangental to the wall in the center of the tube. A stinger is a spin-stabilized rocket. The tooling itself is not too different from strobe tooling or the older whistle tooling I've been told. There is a core and a nozzle. There is a hole drilled tangental to the wall just above the nozzle where the rocket is actually lit. It spins up to speed, and when it hits the core it takes off. They can definitely have a hum to them. A z-bomb is somewhat like a stinger. It's really hard to describe without pictures. Basically there are two angled tangental holes on the bottom which both lift and spin the tube. There is a tutorial on passfire if you're interested. OK, that's cool, I have the Z-bomb tooling and I side light them on a long pin. -dag
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