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I built a tubing bender a few years ago. The launcher was made from scrap bends or mistakes. I love the first picture. I have tried many times to get that shot. I gave the camera to a kid to see if she could get a rocket in flight. She got the "shot" on the fifth picture. Set a bunch of school records the best flew 195 meters! Attached ImagesLast edited by Reebs; 11-19-2010 at 09:09 AM.Dave ReberWadsworth Ohio
Reply:Now that looks like a lot of fun! How does the rocket stay on the launcher until the plate is raised? There must be some type of "tab" built into the bottom of the rocket....Jeff
Reply:Yes The plate slips over the pop bottle flange. See attached photo. Yes it is a lot of fun. It still amazes me to watch as those rockets fly off. I have launched thousands over the years and still get a thrill. Attached ImagesDave ReberWadsworth Ohio
Reply:Picture three of post one. The pipe is just taped on for photo reasons. It really sticks out at a 45 degree angle. It has a groove machined in it for an O-ring to act as a seal to build pressureDave ReberWadsworth Ohio
Reply:What sort of pressure are you launching at? Neat little rig, might need to put one together for junior and I to take out to the fields next to the house.
Reply:120 PSI Put 500 ml of water in the bottle.Go to my web page http://www.blackriver.k12.oh.us/~dreber/for more info.To get to the "plans" look on the left side of the screen and click on Reebz welding. The file is huge so it takes along time to download. If you can compress before down load it will speed up.Dave ReberWadsworth Ohio
Reply:U are so cool why didn't u teach when i was in school can't wait to try out some of your projects keep up the good work my hats of to you and thanks for the dedication to helping teach our youth.
Reply:skidoorev9Thanks science is fun. I get to play with toys all day!Dave ReberWadsworth Ohio
Reply:Read your post a few weeks ago. I have always loved playing with rocket launchers. Built a few as a kid. Now I have tools... so a couple of years ago my son and I built one on a Saturday. Couldn't find it. Didn't have any pics. Finally asked my son and was informed it was in the garage It took me a little bit of looking to find it. My wife controls the garage because I have a shop Originally I wanted to simply use a string to pull the plate... when that proved too difficult I came up with a cam mechanism. We've had this up to the full 175 psi my compressor will give With air only it makes quite a pop when launched and goes pretty good. With water it really goes... but is stealth. For a long time it was near the back door, great for the friendly feud with the guys at the tire shop across the alley I'll take it to the shop tomorrow and put a new o-ring on it... maybe I'll upload a video.Enjoy! Attached Images
Reply:Does anyone other than me remember when they made these bottles and they were blowing up if dropped at the store etc. It took them a while to get the design of the bottle right so that they were safe. I wonder if this was a use for the bottles that the pop companies envisioned. Probably not but darn nice of them to put that big lip there like that.Miller thunderbolt 250Decastar 135ERecovering tool-o-holic ESAB OAI have been interested or involved in Electrical, Fire Alarm, Auto, Marine, Welding, Electronics ETC to name a just a few. So YES you can own too many tools.
Reply:I miss the old flat bottomed soda bottles with the black plastic cap on the bottom. Those things made some great pellet gun silencers!
Reply:Originally Posted by dumb as a stumpDoes anyone other than me remember when they made these bottles and they were blowing up if dropped at the store etc. It took them a while to get the design of the bottle right so that they were safe. I wonder if this was a use for the bottles that the pop companies envisioned. Probably not but darn nice of them to put that big lip there like that.
Reply:celluliod plastics are used in many furniture finishes, plastic packaging, toys and yes ping pong balls. it is also used in smokeless powders if my memory is holding.
Reply:I made a rocket launcher based on the NASA design on their website. It uses two arms which are spring loaded but held closed on the bottle by a loop of string - pull the string & off she goes. The first time I tried it in the driveway, the rocket flew up and knocked the insulation off the power/phone lines. There's something supremely fun about ballistics - kids love it.
Reply:"195 METERS"What's this meters stuff???????We defeated the Germans using inches. We pounded the Japanese to bloody pulp with 16" guns. Built the greatest economy known to man using inches. Railroads, bridges, highways, factories..............all measured and built to the inch.So I suppose that when we decided to export our jobs, we decided to import foreign systems of measurement. Well..........why not?? If you're gonna be a third world country, might as well act like one.Rant over"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by farmersamm"195 METERS"What's this meters stuff???????We defeated the Germans using inches. We pounded the Japanese to bloody pulp with 16" guns. Built the greatest economy known to man using inches. Railroads, bridges, highways, factories..............all measured and built to the inch.So I suppose that when we decided to export our jobs, we decided to import foreign systems of measurement. Well..........why not?? If you're gonna be a third world country, might as well act like one.Rant over
Reply:I here ya on the export of our jobs, but I will say this; if you ever learn to use the metric system, you'll hate the old English system that we currently use!"The man of great wealth owes a peculiar obligation to the State, because he derives special advantages from the mere existence of government." Teddy RooseveltAmerican by birth, Union by choice! Boilermakers # 60America is a Union.
Reply:Originally Posted by farmersamm"195 METERS"What's this meters stuff???????We defeated the Germans using inches. We pounded the Japanese to bloody pulp with 16" guns. Built the greatest economy known to man using inches. Railroads, bridges, highways, factories..............all measured and built to the inch.So I suppose that when we decided to export our jobs, we decided to import foreign systems of measurement. Well..........why not?? If you're gonna be a third world country, might as well act like one.Rant over
Reply:To get back to the topic at hand... the rockets! Replaced the o-ring and grease up the mechanism. Shot two quick video clips. Luckily we didn't hit any cars. The first one is with air only and it makes a nice pop, after refilling (2x video speed) shot one with water. It landed on the roof... so no more fun. During the filling I think you can hear the plastic groaning http://home.lewiscounty.com/~forhire/rocket_demo.wmvEnjoy!
Reply:Originally Posted by forhireTo get back to the topic at hand... the rockets! Replaced the o-ring and grease up the mechanism. Shot two quick video clips. Luckily we didn't hit any cars. The first one is with air only and it makes a nice pop, after refilling (2x video speed) shot one with water. It landed on the roof... so no more fun. During the filling I think you can hear the plastic groaning http://home.lewiscounty.com/~forhire/rocket_demo.wmvEnjoy!
Reply:OK Farmersamm the rocket flew 7677 inches!!!!!!!!!!!!!!!Additionally the United States will be fully metric by 1982!The metric system is so much simpler I love it look mom no fractions.Forhire I have found about 500 ml of water is the best.175 PSI man that is a bunch. I saw a guy how drills a hole n the bottom of two bottles and bolts them together with a hollow bolt from a lamp adding more air volume. Im going to try that in the spring to see what happensDave ReberWadsworth Ohio
Reply:Originally Posted by bert the welderThat's awesome! I think I'd want a string though, just in case! Anyone want to try some flammable gas???
Reply:Originally Posted by ReebsForhire I have found about 500 ml of water is the best.175 PSI man that is a bunch. I saw a guy how drills a hole n the bottom of two bottles and bolts them together with a hollow bolt from a lamp adding more air volume. Im going to try that in the spring to see what happens
Reply:By zora, Guess what I'm building next? I am all for the flammables. Propane might be interesting. Don't think that I would use gasoline though. Maybe alcohol and move up from there. Night launches. I'm getting excited just thinking about it. Definitely need a string to launch it though.
Reply:Originally Posted by zoraGuess what I'm building next? I am all for the flammables. Propane might be interesting. Don't think that I would use gasoline though. Maybe alcohol and move up from there. Night launches. I'm getting excited just thinking about it. Definitely need a string to launch it though. This is what I had when I was little.Originally Posted by Swampy79Respectfully I used to agree with you, in fact I resented and resisted embracing the SI system through the first 2 years of college pursuing my engineering degree. Then I learned better. It dawned on me during the middle of a final exam where I realized that a problem using our beloved english system took about 50% longer to do because it required a god awful amount of conversions, for base 10 systems you're just moving decimals, and that is a beautiful thing when you have to design by data and calculation. There's a reason even the english moved away from their namesake system, so much chance for error is eliminated.with that said, in the shop everything comes off our tape anyways so inches/feet don't hamper any progress anyways (although if they switched all tapes to cm/meter and thats all you could buy most of us wouldn't skip a beat picking it up and making it second nature).SI was obviously developed by a devoted follower of the K.I.S.S. system and you can't argue with that kind of beauty.
Reply:this looks way too cool. I need to make one for the kids. I'm lost about the water??? Daye
Reply:I believe the water gives it some mass so when shot, it goes higher. Its like throwing a balloon at someone with air vs throwing a balloon with some or full of water.
Reply:Conservation of momentum.The mass of the water multiplied by the speed of the water exiting = the mass of the rocket multiplied by the speed of the rocket.http://www.tutorvista.com/content/sc...-third-law.php------------------------------Lincoln 175HDLincoln AC/DC225Smith O/A
Reply:cnywelder and oxygen454 have nailed it. The more mass you push out the the back the father it goes in the other direction. Newtons 3rd law Action/reaction. For ever action there is an equal and opposite reaction. I have found 500 ml of water is best.They are fun my students love it.Dave ReberWadsworth Ohio
Reply:Originally Posted by farmersamm"195 METERS"What's this meters stuff???????We defeated the Germans using inches. We pounded the Japanese to bloody pulp with 16" guns. Built the greatest economy known to man using inches. Railroads, bridges, highways, factories..............all measured and built to the inch.So I suppose that when we decided to export our jobs, we decided to import foreign systems of measurement. Well..........why not?? If you're gonna be a third world country, might as well act like one.Rant over
Reply:Hey Reebs, I modified my launcher a little. Thought I'd post a picture. My Dad wanted to borrow the launcher for a camp out at his place. I decided it was time to make it more user friendly by attaching a pull rope. I had always planned on this but couldn't decide on a design. The original small foot print was prone to tipping over when pulled hard.I cut the base out of some scrap plate on the plasma table. I included a carry handle in the design. Tack weld the launcher in place and called it good. Nice and stable now! Didn't even have time to paint it before he needed it. As usual the kids loved playing with it. Attached Images
Reply:What is the diameter of the radius for the notch that goes around the bottle? This is definitely something that is going onto the top of the to do list. My kids would love it. though, My neighbor (father in-law) might notThere are no problems. There are only solutions. It's your duty to determine the right one.Hobart Handler 210Airco 225 Amp MSM Stinger
Reply:Forhire I like it!! Nice and simple. Mine is screwed to a piece of plywood to hold it in place.I have seen a few like that. Make sure every one is back and wearing safety glasses. I pump the bottles up to 120 psi. 1 out of 50 bottles explodes, it will scare the Sh@t out off you.Thanks for the update.Dave ReberWadsworth Ohio
Reply:Need to make one.Are those one liter bottles half full of water?What is the psi at launch? Thanks
Reply:Mine are two liter bottles and they have 500ml of water. PSI at launch is 120. If you wrap the bottle in D. tape you MIGHT be able to go to 160psi!!!!!!!!!!!!I will post a picture over the weekend of how to make the pressure bottle 4 liters.Dave ReberWadsworth Ohio
Reply:I always wanted to make a steam powered rocket out of something like a fire extinguisher or tiny oxygen bottle (small plumbers type). Yes, it could be very dangerous if not done properly.I was thinking of turning a nozzle that screws in after removing the valve. The orifice on the nozzle would be filled with some low melt point casting metal (as low as 150F melt) or lead/tin solder (360F melt). An electric heating element would be installed in the nozzle before filling with the casting metal.In operation you'd fill the bottle mostly full of water. Then screw in your pre-assembled plugged nozzle with heating element and set it up in the launch tube or rod. Hook up the heating element to a very long wire so you can get the hell away from it. Plug in the element and wait for the temperature to reach the melt point of the casting metal. When the temp gets high enough the casting metal will melt and the pressure will blow it and the heating element out.Water at 360F (lead/tin solder melt temp) would produce steam pressures around 400psi. This would be a fair margin on a 2400psi oxygen cylinder. How do you derate the cylinder because of the increased temperature?First tests would be with the cylinder strapped down. You'd need to change the tweak the nozzle size. You may be able to take some video or photographs and see the steam plume to see if it's underexpanded or overexpanded. I haven't figured out if there's enough energy in 360F water to totally convert it into steam. If not, then there may not be any use in using a nozzle since liquid water won't expand.For flight you'd need fins to stablize it. Don't weld anything on the cylinder. Make hoops from flat stock that tighten around the cylinder. Then weld whatever you need to the hoops.The cylinder is going much heavier than the plastic soda bottle. Will there be enough thrust to make it fly well?Dynasty200DX w/coolmate1MM210MM VintageESAB miniarc161ltsLincoln AC225Victor O/A, Smith AW1ACutmaster 81IR 2475N7.5FPRage3Jancy USA1019" SBAEAD-200LE
Reply:Andy,Please refer to Mythbusters "waterheater rocket".[ame]http://www.youtube.com/watch?v=rGWmONHipVo[/ame]water under preasure.There are no problems. There are only solutions. It's your duty to determine the right one.Hobart Handler 210Airco 225 Amp MSM Stinger
Reply:Originally Posted by ThorsHammerWhat is the diameter of the radius for the notch that goes around the bottle?
Reply:Originally Posted by ThorsHammerAndy,Please refer to Mythbusters "waterheater rocket".
Reply:Launching the rockets is by far my favorite activity to do with the kids. I launch the kind of crappy looking rockets first and save what look like the best rockets for last. Last year we had the first few fly maybe 50-70 meters. The kids thought it was cool. Then we hit a bunch 170 meter flights the kids mouths fell open as they watched them go. It is crazy what air and water can do.Dave ReberWadsworth Ohio
Reply:Originally Posted by ReebsAdditionally the United States will be fully metric by 1982!The metric system is so much simpler I love it look mom no fractions.175 PSI man that is a bunch.
Reply:Originally Posted by farmersamm"195 METERS"What's this meters stuff???????We defeated the Germans using inches. We pounded the Japanese to bloody pulp with 16" guns. Built the greatest economy known to man using inches. Railroads, bridges, highways, factories..............all measured and built to the inch.So I suppose that when we decided to export our jobs, we decided to import foreign systems of measurement. Well..........why not?? If you're gonna be a third world country, might as well act like one.Rant over
Reply:VPTIt is odd all my science nerd friends us metric and english units depending on the conversation or topic. But with repect to pressure they all pretty much use PSI.Dave ReberWadsworth Ohio
Reply:Originally Posted by farmersamm"195 METERS"What's this meters stuff???????We defeated the Germans using inches. We pounded the Japanese to bloody pulp with 16" guns. Built the greatest economy known to man using inches. Railroads, bridges, highways, factories..............all measured and built to the inch.So I suppose that when we decided to export our jobs, we decided to import foreign systems of measurement. Well..........why not?? If you're gonna be a third world country, might as well act like one.Rant over
Reply:you can hem and haw about not using the metric system, but when it comes down to it, It's a far simplier, far easier to use system than the Inch. Multiples of 10 are far easier to understand and utilize than multiples of 12, or the fractions there in. 2 cm is far easier to use that 5/8" or even .625".The only reason we don't change over is due to pure arigance and stuburness. "we didn't do it, it can't be worth a damn."There are no problems. There are only solutions. It's your duty to determine the right one.Hobart Handler 210Airco 225 Amp MSM Stinger
Reply:You do know that for engineering as in roads and grading dirt and measuring lotswe use engineering scale which 1 foot divided into 10 increments called tenth and each tenth has ten increments call hundredths it has been used for surveying foreverAnd it is easy to do calculations like the metric system also easy to signal to the equipment operator how much to cut or fill at a certain place to achieve gradeBacked my CATMA over your CARMA oops clusmy me What would SATAN do ?? Miller Trailblazer 302 AirPakMiller Digital Elite Optrel Welding HatArcair K4000Suitcase 12RC / 12 VSHypertherm PM-45Rage 3 sawRusty old Truck
Reply:Instead of fireworks (they are illegal here and require a 1.5 hour drive to Wyoming), my friends and I have taken a great interest in dry ice bombs. We have found that Dasani water bottles are the best, and usually the failure is out the side, rather then the cap separating. We also found that duct tape does not hardly make a difference. We would use these as propellant and then put an empty lid off 5 gallon bucket over it. I think the best we got was about 60 feet. These are very very dangerous unless you know what your doing. But to test the capabilities of your water bottle you might try this with a pressure gauge that has a top/hold function. Also with working at high pressure a wood blast shield would probably be smart 14' PowerMig 210 MP13'Burntables 5x10 CNC Table14' SAE300 HE on a 12' Ram 4500 60 CA 4x4. Custom bed/bottles/reels.87' SA250d, 78 SA200,11' Ranger 250 GXT AC/DCThermal Dynamics Cutmaster 8112' Lincoln Precision Tig 22508' LN25
Reply:I'll admit I am new here but, a question if I may, forhire how come if the metric system is so cool, you refer to pressure in PSI isn't the pounds per square INCH? It would seem some of us aren't as converted as we think. hmmmmm
Reply:Originally Posted by JohninazI'll admit I am new here but, a question if I may, forhire how come if the metric system is so cool, you refer to pressure in PSI isn't the pounds per square INCH? It would seem some of us aren't as converted as we think. hmmmmm |
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发表于 2021-8-31 22:27:35