starlight Posted April 26, 2007 Share Posted April 26, 2007 perhaps the metalllo used e' of the aluminum to grains the sound that emits e' much metallic one, dipendera from the diameter of the hole hole Link to comment Share on other sites More sharing options...
h0lx Posted April 26, 2007 Share Posted April 26, 2007 Say what? Link to comment Share on other sites More sharing options...
hst45 Posted April 26, 2007 Share Posted April 26, 2007 perhaps the metalllo used e' of the aluminum to grains the sound that emits e' much metallic one, dipendera from the diameter of the hole holeI'll try this one: "Perhaps the size of the metal used to gain the sound should be dependent on the size of the nozzle." That's my best guess. Link to comment Share on other sites More sharing options...
cplmac Posted April 26, 2007 Share Posted April 26, 2007 Go getters don't have a nozzle, although the wet batched ones do form a small concave cavity as they dry. Link to comment Share on other sites More sharing options...
cplmac Posted April 28, 2007 Share Posted April 28, 2007 3lb Whisper rocket with 7 1.25" glitter comets 3" Drippy Comet 3lb Red and Green Strobe rocket 6lb Whisper rocket with 3" comet to report Okay, couple of things here, first these aren't the greatest videos, but they are good enough. Second, the red green strobe rocket was awesome in person. The motor burned green and strobed red, but like all of my strobe rockets it hit the ground before the report could go. The Drippy glitter formula for these large comets needs to have the Ti removed. It gave a longer tail but killed the glitter of the Al. Link to comment Share on other sites More sharing options...
qwezxc12 Posted April 28, 2007 Share Posted April 28, 2007 cplmac, First off, nice videos... The strobe rocket partially eclipsing the moon was too cool. Did you already post your drippy comet formula? I have a nagging suspicion you did, but I didn't come across it in a quick scan through your posts. Could you post it or point to the post where you did...it's really nice. Do you pump the comets with a commercial or home made form? Link to comment Share on other sites More sharing options...
cplmac Posted April 29, 2007 Share Posted April 29, 2007 I don't think I did because I haven't settled on it yet. I've been tweaking it for months, and this last one is actually another tweak. Basically I used the Purrington gold glitter formula, and just started messing with it changing the metal types and ratios. The reason this last on had such a massive tail is the coarse Ti. I pressed it on Wolters 2.5" comet pump which absolutely kicks ass. You can get that massive pump with a crossette and a cavity head as well. Link to comment Share on other sites More sharing options...
qwezxc12 Posted April 29, 2007 Share Posted April 29, 2007 OK...I do remember you posting the Purrington's info. Yeah, Rich's tools are nice - I have some crossette tooling and case extenders. I asked as I have come up empty for an easy 2 1/2" - 2 5/8" ID comet mold. Still hoping I've overlooked some sort of pipe fitting that will do the trick. Fabbing up a rammer from HDPE or PVC + wood/epoxy, etc. is doable, but I may have to bite the bullet and purchase some large comet pumps. The 2" comets I make weigh in ~50g ea. How much do the 3" weigh? Link to comment Share on other sites More sharing options...
Mumbles Posted April 29, 2007 Share Posted April 29, 2007 I'll let cpl answer for sure, but I believe he said the last comets weighed 300g. For a 3" (cheap) comet pump, I've been looking into a few things. First and foremost (and cheapest) 2.5" PVC. 2" PVC should slide in fairly easily, or at least with a bit of sanding. I've also thought about using the passfire method, where they cut a strip out of larger PVC and heat form it to size. I'd be a bit uncomfortable having the outer sleve split though. I'd much prefer it be the inner sleve, but this brings us back to the 2.5" PVC The other, and probably highest quality, thing I've been thinking of is picking up some metal. 2.5" aluminum with a 1/4" wall is fairly standard it seems, One could pick it up for $20-30 a foot from what I've seen. You really only need 4-6" anyway. 2.5" solid rod is also available, but the PVC thing mentioned before could work too. I'm not sure how well the aluminum would hold up to the pressing pressure. Steel is available, but more pricey. I also would probably make my rammers from PVC so I could make several rammers. Solid, cored, off center cored, etc. Would also do the same thing for 1.75" comets. If anyone tries this out let me know how it works. Link to comment Share on other sites More sharing options...
cplmac Posted April 29, 2007 Share Posted April 29, 2007 Mumbles is right on the comet was 315 grams when dried. I press these comets at 4000 PSI indicated on a 1.75" hydraulic ram going into a 2.5" tooling ram. I don't think PVC would hold up to this pressure. I'm pretty sure my tooling is about 9 inches long and I use most of it because at that pressure the comp really compresses to less than half it's loosely filled size. Link to comment Share on other sites More sharing options...
h&k machineguns Posted May 2, 2007 Author Share Posted May 2, 2007 1 pound single core whistle rocket 3800-4000 feet. Enlarge the youtube screen,and turn it up. http://youtube.com/watch?v=EndKq_SWoIo Link to comment Share on other sites More sharing options...
pudidotdk Posted May 2, 2007 Share Posted May 2, 2007 Wow, that was indeed a fast rocket! What mixture/procedure did you use and how was the construction of the rocket? Link to comment Share on other sites More sharing options...
h&k machineguns Posted May 3, 2007 Author Share Posted May 3, 2007 Wow, that was indeed a fast rocket! What mixture/procedure did you use and how was the construction of the rocket?I like my rockets fast,and feel the faster the better . I also like lots and lots of thrust. If I could I would make them twice as fast and 5 times higher,but I may be reaching my limits as far as what a paper tube can handle. I build whistle rockets out of schedule 40 PVC pipe as well,and can put a little hotter fuel in them.In that video,I used NEPT tubing ,76/23/1-3 using Sodium sal,and Tai Perc,red iron oxide,with vasoline. The core is 4.25" long,and I go about half way up the core with this fuel,then the rest of the core with 64/32/1-3 using the same chems. I screened the perc through 30 mesh,before mixing everything together,and use laquare thinner . Link to comment Share on other sites More sharing options...
cplmac Posted May 3, 2007 Share Posted May 3, 2007 Man that thing was a bullet HK. Link to comment Share on other sites More sharing options...
cplmac Posted May 8, 2007 Share Posted May 8, 2007 Standard hummer style, my mix. 2 vent hummer. One vent fused. Open ended hummer, one end plugged the other exposed pressed fuel. That last one had a really cool wind down sound, but it may have been from the 20' bounce it took straight up. Link to comment Share on other sites More sharing options...
deadman Posted May 8, 2007 Share Posted May 8, 2007 That sound was definitley very sci-fi. Are your hummers normally so short lived? Did something happen to your bandwidth limits? theskypainters.com videos seam to be loading much faster than they used to. Link to comment Share on other sites More sharing options...
cplmac Posted May 8, 2007 Share Posted May 8, 2007 My hummers are always short, I can't seem to get any longevity with the current tubes, I think they are about a quarter inch to short. I'm not sure what is with the bandwidth I have no idea, sometimes the net is a slug, sometimes it's working right. I have never even used 1% of my bandwidth so if it's slow it's a traffic jam on the net most likely. Link to comment Share on other sites More sharing options...
h&k machineguns Posted May 12, 2007 Author Share Posted May 12, 2007 5000+ foot 1 pound whistle rocket. Single stage 3/4" ID 7" long tube. From flash to noise 5.17 seconds http://youtube.com/watch?v=jZx1DEoW43o Link to comment Share on other sites More sharing options...
cplmac Posted May 15, 2007 Share Posted May 15, 2007 That is the longest burn time I've ever seen for a 1 pound rocket, hell any single stage. What fuel did you use? Great stuff as usual HK. 3" Ti Whistle Mine I was not impressed, but it did work. Would have been much better at night, but even in the day you can see the 10% Ti. Link to comment Share on other sites More sharing options...
h&k machineguns Posted May 15, 2007 Author Share Posted May 15, 2007 Thanks cplmac, The fuel was Sodium Sal,Tai Perc, and vasoline. I'm going to add a booster to it,and see if I can get 6500 + feet. Link to comment Share on other sites More sharing options...
cplmac Posted May 15, 2007 Share Posted May 15, 2007 No catalyst? I guess that would make the burn duration longer. I look forward to seeing the next one. I built and fired a 3 stage 2 pounder this weekend. I'll get the video up as soon as it's rendered. Link to comment Share on other sites More sharing options...
cplmac Posted May 15, 2007 Share Posted May 15, 2007 I think this is the best rocket I've ever made. 3 stage 2 pound rocket Link to comment Share on other sites More sharing options...
fight fire with fire Posted May 15, 2007 Share Posted May 15, 2007 Shit cplmac! That was absolutely fucking beautiful man! Dude wish i could do that. By any chance is your name Kevin? Link to comment Share on other sites More sharing options...
optimus Posted May 15, 2007 Share Posted May 15, 2007 That was sweeet - nice tracking work with the camera ; ) Do you have a pre-fire photo? Link to comment Share on other sites More sharing options...
pyro4life Posted May 15, 2007 Share Posted May 15, 2007 That was the best rocket iv seen! Was is just 3 variations of benzoate whistle? Link to comment Share on other sites More sharing options...
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