Big Ass Rocket

[cplmac]

I finally stepped up to the 3" ID rocket, pressed two of them today. I'll have the videos posted as soon as possible, in the meantime here are the pre-fire pics.

 

http://pyrobin.com/files/p8240004.jpg

this is the first one I pressed, fired it off earlier just waiting on video rendering.

 

http://pyrobin.com/files/p8240002.jpg

this one is being fired tomorrow, video will posted later

 

http://pyrobin.com/files/p8240006.jpg

this is the second rocket with a tape measure for scale

[rocket]

My god they are big, I’m guessing they are whistle rockets? Be an interesting cato if they do, hope that doesn’t happen though. Good luck.

[qwezxc12]

Good Lord man! Where did you steal the fence post for the stick? Those are the biggest rockets short of composite fuel high-altitude stuff I have ever seen. Are you going to put up shells with them after they're dialed in? I wonder what lifting capacity they'll have.

 

As rocket asked, are they whistle or BP core burners? What sort of pressure does your press need to generate to consolidate the fuel in an ID that big?

[Pretty green flame]

Holy cr**, that's a massive rocket. Good luck with the firing. I hope it flies well.

[cplmac]

Thanks, I fired the first one off tonight and it worked like a charm. They are whistle rockets, and they really scream, the first one the delay grain fractured and it started chuffing like a huge strobe rocket. I'd like to do one BP, probably the next one will be BP. I think it could easily haul a 10 pound payload, since I handcored the core I can size it to suit the rocket specifically. The first one had a core that was 1.5"x5" the one I'm shooting tomorrow is 1.5"x4". I thought the first one was just a little fast, and that core can carry some real weight I think. As far as pressing I pressed the fuel at 10,000 indicated, which translates to something like 3500 on the grain. It worked okay and that is about the limit for the stock pressure guage. I'm going to pull that guage off though, I have a 0-15000 guage mounted on the hydraulics too, so I'll just use that one. I actually came real close to making a trip to the hospital pressing the first one. My set up on the press had a 0-5000 guage and the stock guage. I installed a cutoff valve for the 0-5000 guage for when I need to press a large high pressure rocket like this one. Well, I saw a few drops of hydraulic fluid dripping from the bottom of the valve so I leaned in to take a closer look, when my head got about 6" from the valve it exploded. Fortunately it blew in one direction, but I had to rebuild the hydraulics to finish the second rocket. Anyhow, I'll try and get the videos up Sunday night.

[frogy]

Man, when stuff like that explodes it always scares the crap out of me...

 

 

Lol a 6lb. rocket is 1-1/2 by 16" right? what the hell is that? 3" by 16" lol

 

A 3" ID Rocket would essentially be a 46 to 48 lb. rocket... not weight, but by specifications of... the weight of a pure lead ball that just rest on top of a tube that the rocket fits into...

 

 

Those things really have to scream... they have to look beautiful =)

[Gottagotomoz]

Big ass rocket indeed! Can't wait to see the video. What was the approx. height at its apogee? Also, was the tube hand rolled?

[ULTRABUF]

Wow. Those have quite the impressiveness factor. Can't wait to see one on video man, if apc had a big ass rocket award, you would be all time champ.

[Mumbles]

I saw it in person today, and I can verify it's impressiveness. Many pictures were taken of cpl and the rocket.

 

BTW, a 3" ID rocket is a 60lb rocket. The mass rating is given by the mass of lead spheres the ID of the tube able to fill the tube completely, normally 10 balls. I assure you this one wasn't 30in long though. The old system was designated for BP rockets, which are generally 10 ID long. Whistle rockets are shorter, but keep the same conventions.

[frogy]

I was misinterpreted because... I read the wiki for "Skyrocket" a few months ago and it says the "weight" classification (2oz.,4oz.,8oz.,1lb.,2,3,4,5,6...) is derived from the mass of a lead ball that JUST rest on a tube that the rocket JUST fits into....

 

For a 1 pound rocket... say .375 (radius) +0.0625 (1/16" wall) +.05 (for the just just thing = .4875 (radius)

 

Volume of sphere = .485 cubic in = 7.95 cc

7.95 cc * 11.34 (density of lead) = 90.15 g.... Definately not 453 grams... How did they get info that is so inaccurate? (idiots that edit wiki not knowing what they're talking about)

 

Now your method... .375 radius = .22 cubic in = 3.6 cc x 11.34 = 40.824 x 10 = 408.24 g much closer to 1 lb...

 

Now if you add in a 1/16" wall you get... .4375 radius = .35 cubic in = 5.735 cc x 11.34 = 65.03 x 10 = 650.3 grams... over 1 pound... so I guess they just round up the 408 gram to the neareast from 14.4 oz to 16 oz?

[cplmac]

3"ID Ti Whistle To Report, Windows Media Player Compatible

[frogy]

That was amazing... Beautiful rocket man... It sounded like a real nice whistle Most of your sound like that, elephants or something

 

That was a powerful report also?

[Mumbles]

Only if you think a pound and a half of flash is that powerful.

[ULTRABUF]

Sweetest rocket vid ever.

[jacob]

A POUND AND A HALF! aghhh stop useing so much perc, you guys do know that lightly confined AN/AL can be set off with good, well confined 70/30 flash, don't you? i know a guy personally who's done this successfully. but i do love the sound that rocket makes, it's like a elephant/mooing sound, and it looks like it whent straight up too, and it's also cool how the sound is slightly off from visual i guess because it whent so high. .

[Mumbles]

Pyro clubs tend to frown upon the use of high explosives, which is what AN/Al is classified as. AN introduces other incompatibility issues and such that many don't care to work with.

[jacob]

Ahhh, i knew there must have been a reason, but if your in a club i would asume you can get lots of cheep perc anyway so nevermind, still, that much flash would be scary to mix , i would feel safer with AN/AL. EDIT. man that movie gets better every time i watch it, best rocket ever .

[hst45]

cplmac, I've been an admirrer of your work for some time and you've out-done yourself yet again. Have you ever thought of branching out from the pyro-rocket genre into the, what the hell would you call it, Werner Von Braun catagory? You know, build a rocket with fins, carry a scientific payload, measure the atmospheric pressure at 72,000 feet......and THEN blow the 1-1/2 lb. flash header! That would make you a world renowned scientist instead of a pyro mental patient ! O'Hare international would clear airspace for your work. "No flights are allowed between Bismark and Sioux Falls, cplmac has a 42" diamater, 19 foot long whistle-Ti sponge-ethyl perchlorate prototype coming up at 6:00 P.M." The flash would be seen from Nome to Buoenes Areas.

 

O.K., maybe I exagerate.....It might not be visible in Nome.........

[FrankRizzo]

cpl may chime in on this, but according to his post on Passfire, the header was close to *3lbs* (though that may have been the combined weight of the casing & report comp).

 

BTW, cpl, thanks for posting your latest videos in MJPEG(.avi) instead of MPEG-4(.mp4). For some reason, both VLC media player and WMP would only show part of the frame, and I had to use quicktime instead to view all your vids. I hate Quicktime..they bundle too much shit with their player.

[cplmac]

Frank you got it right, the three pounds on the header is the flash plus the casing it was in. I built a cylinder salute with a 5" piece of the same tube the motor was made of and attached it to the top of the rocket. So the flash was about a pound and a half and the tube, end discs, pasting, spiking blah blah blah was another pound and a half. The tubes are pretty thick. On the video side, all the MP4 videos I took with my Olympus. There were two advantages to those videos, I could post them in less than five minutes, and YouTube used to like the format. I personally HATE quicktime and the MP4 format in general. We used our Sony FX-1 HD camera to take the video of the rocket, only problem is that I have to wait for my brother to do the rendering. The source video is like almost everything else from Sony, proprietary and terminal with DRM so rendering to a different format requires some expensive software that my brother has. Right now he is researching different WMP compatible HD formats to convert to so everyone can enjoy these in HD which is how we actually recorded them.

 

hst I have actually considered using small vanes on the bottom of my stick on large rockets to help compensate for the weight/balance issue, but much to my surprise so far the big rockets have flown pretty darn straight. I'm half convinced you could fly one straight without a stick.

[Mumbles]

hst I have actually considered using small vanes on the bottom of my stick on large rockets to help compensate for the weight/balance issue, but much to my surprise so far the big rockets have flown pretty darn straight.  I'm half convinced you could fly one straight without a stick.

I volunteer to be nowhere near that thing on your first test.

 

Not exactly related, but I have heard adding a nose cone, or at least a hemisphere to the top of the normally flat rockets, make them fly significantly higher. I was hearing 500 feet higher on normal 1lb whistle rockets. That is somewhere between 25 and 50% higher than normal.

[Aquarius]

Mumbles, you are correct on the nose cone bit.

Adding a nosecone will seriously decrease the wind-drag of the rocket. A flat nose cone is the worst ( well, a hollow point is even worse..) and a parabolic nosecone is among the better ones.

 

The nosecone will lessen the drag, and also impact on stability since the air now flows equal on all sides of the rocket body.

A flat nose cone could make the rocket "trip" in the air, and drasticly alter the direction it's flying. Now, with a rocket that size AND 1,5 lb flash, that could be the recepie of disaster..

[psyco_1322]

cplmac, I've been an admirrer of your work for some time and you've out-done yourself yet again. Have you ever thought of branching out from the pyro-rocket genre into the, what the hell would you call it, Werner Von Braun catagory? You know, build a rocket with fins, carry a scientific payload, measure the atmospheric pressure at 72,000 feet......and THEN blow the 1-1/2 lb. flash header! That would make you a world renowned scientist instead of a pyro mental patient ! O'Hare international would clear airspace for your work. "No flights are allowed between Bismark and Sioux Falls, cplmac has a 42" diamater, 19 foot long whistle-Ti sponge-ethyl perchlorate prototype coming up at 6:00 P.M." The flash would be seen from Nome to Buoenes Areas.

 

O.K., maybe I exagerate.....It might not be visible in Nome.........

HAHA, that one made me laugh. Just the way I read it, its was pretty funny at the time.

[cplmac]

I sent up another one tonight at the HPA get together. This one was a little bit lighter and flew a bit higher. I headed it with 5 2.5" salutes and 2 3" salutes. I'll see if I can get the video up tomorrow. Interestingly enough, I live twenty minutes from O'hare, and work on the north border of the airport.

[tentacles]

Nice! I look forward to the video. FrankRizzo has a crapload of your tubes in his garage, and I have to say, they are just ridiculously thick walled. Descriptions just don't do them justice. The walls (combined) are almost as thick as the diameter!

 

Since you're definitely going to have these things tuned in by PGI, why not go for a 3" rocket GIRANDOLA? That would be insane! 100lb payload maybe?

 

Please note that this post may have been made under the influence of some whiskey.