Hey Reebs... hydrostatic tester for soda bottle rockets

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So several years ago my son and I spent a Saturday building a soda bottle rocket Iaucher and I posted some pictures to Reebs thread: weldingweb.com/vbb/showthread.php?t=46678 Ever since that thread I have really wanted to do some hydrostatic testing of some pop bottles. I know from experience that most let go someplace between 175 and 200 psi. But I really wanted to be able to play. I have looked at commercial testers like Wheeler-Rex that do 300 psi and 1000 psi but they are a bit more than I wanted to spend for a "toy".http://www.wheelerrex.com/wheeler-re...g-page-28.htmlSo a while ago I recall seeing someone that had made an injector tester from a cheap hydraulic jack... and I thought that may work... so a few minutes reading and I was ready to start building. http://www.peachparts.com/Wikka/DieselInjectorTesterBeing that I have a lathe and such I decided to improve on the design a little.Pic1 open the jack with a big wrenchPic2 drain all the oilPic3 turn a part that is 21.95mm for about 25mm (1 inch) then step up to 23.95mm for about 50mm (2 inches). The length of the second part could be as long as the bore. You just need to ensure the seal is below the relief hole. Test fitting the top.Pic4 drill 5/16" hole clean through.Pic5 tap for 1/8" NPTI didn't get a picture after I cut the groove for the snap ring. More pictures coming.  Attached Images
Reply:Some more build pictures.Pic1 Parted off the part, flipped it, and machined the bottom face.Pic2 Nearly completed part.Pic3 Put the part in the indexer and machined a 19mm hex. This will make assembly a lot easier. Yeah, I know I really need a set of metric collets. Pic4 Installed the pressure gauge and fittings.Pic5 The complete unit installed with a length of hydraulic hose to the launcher. Attached Images
Reply:Here are the last of the photos for tonight. I only had enough time to set one soda bottle this morning. I wasn't able to get all the air out of the bottle so it popped a little more than expected. I'll setup to film some videos during the week if I have time.Pic1 Bottle popped the label at around 180 psi. This photo is at 190 psi. I was suprise how much water it took on as it grew... I also appear to stretch... it would lose psi but now water.Pic2 Burst as 200 psi.Pic 3 The bottle. I was surprised that it split all the way down the neck.This week I'll weld on a hose fitting so I can so larger bottles faster. I also need to bleed off the air more completely. Let the fun begin.  Attached Images
Reply:So I had a few things to do at the shop late tonight so I decided to make the 1/8 NPT bung to replace the rubber fill stopper while I was there. This will allow more water to be added and if plumbed to a graduated measure will allow to monitor and record the expansion. More pics... nothing special.   Pic1 Started with a 7/8" drop. Turned to diameter, drilled and tapped. Parted off.Pic2 Put on indexer and cut the 19mm hex (quick because I was already setup from this morning).Pic3 Bored the 24mm radius to match the housing. Pic4 Finished radius.Pic5 Mocked up part. I'll disassemble everything and weld it up on Monday. Attached Images
Reply:Looks Fun!
Reply:You should be able to test air compressor tanks with that also. Its real similer to my purchased Hydro tester except mine goes up to I think 2000 lbs.  Mac
Reply:Man you must be having fun! Nothing wrong with that!Lincoln 305GLincoln 100 WeldpakAssortment of Victor, Smith and Harris TorchesDont Worry About the Mule-Load the Wagon!Lincoln 305GUnion Carbide TorchDon't Worry About the Mule~Load the Wagon!
Reply:Originally Posted by Novaboy66Looks Fun!
Reply:Originally Posted by forhireMy purpose for building this test rig is purely educational... although I imagine now that I have a tester... I'll find some good uses.  I have wanted to put together a visible demonstration comparing the use of hydrostatic testing vs air testing. Pop bottles should provide a relatively safe small scale demonstration.
Reply:Finished the pump this morning. Welded on the bung and installed the garden hose adapter. Added the tire valve back into the system so I can charge it with air if I want to. I have way too much time into this toy.  Attached Images
Reply:Originally Posted by DSWI think you've been watching too much "Mythbusters"...I know I have. Be sure to put some styrofoam bodies or action figures around the bottles when you blow them up both with water and with air so we can see the fragmentation patterns and blast damage. Video would be cool as well... After all what's the fun in testing a good myth if you can't watch something blow up?
Reply:Fantastic I just caught the thread. When the bottle lets go ..... It lets go!!!!!!!!!!!!!!!Dave ReberWadsworth Ohio
Reply:Originally Posted by ReebsFantastic I just caught the thread. When the bottle lets go ..... It lets go!!!!!!!!!!!!!!!
Reply:I wish you would have come up with this earlier.  I threw out a fairly new 20 ton jack with a swelled up cylinder.  That wouldn't have made any difference for something like this.My name's not Jim....
Reply:Neat build, Forhire.Good job!I wonder if a high-pressure "long range" missile could be made by wrapping the barrel with something like fiberglass reinforced tape?Has anybody tried CO2 propellant?Good LuckLast edited by denrep; 02-21-2012 at 08:33 AM.
Reply:Thanks for sharingNext year when we build rockets I will have the kids put the green on the bottom!!!!!!!!!!!Dave ReberWadsworth Ohio
Reply:Originally Posted by BoostinjdmI wish you would have come up with this earlier.  I threw out a fairly new 20 ton jack with a swelled up cylinder.  That wouldn't have made any difference for something like this.
Reply:Originally Posted by forhireHere are the last of the photos for tonight. I only had enough time to set one soda bottle this morning. I wasn't able to get all the air out of the bottle so it popped a little more than expected. I'll setup to film some videos during the week if I have time.Pic1 Bottle popped the label at around 180 psi. This photo is at 190 psi. I was suprise how much water it took on as it grew... I also appear to stretch... it would lose psi but now water.Pic2 Burst as 200 psi.Pic 3 The bottle. I was surprised that it split all the way down the neck.This week I'll weld on a hose fitting so I can so larger bottles faster. I also need to bleed off the air more completely. Let the fun begin.
Reply:Had a 16 ounce Sprite with lunch yesterday. It bottle felt thicker than the top performing Sierra Mist bottles. Figured I'd put one to the test. Ruptured at 200 psi. I didn't even get wet.  Attached Images
Reply:have you considered using the lathe and some PVC to build a nozzle?  Something still light, but maybe a 1/4" hole to reduce the thrust, but lengthen the time of the thrust.. I bet you could get a lot more height with some trial and error on the hole size!miller syncrowave 250hobart handler 140home made 400 amp engine driven in progress...
Reply:Originally Posted by jdchmielhave you considered using the lathe and some PVC to build a nozzle?  Something still light, but maybe a 1/4" hole to reduce the thrust, but lengthen the time of the thrust.. I bet you could get a lot more height with some trial and error on the hole size!
Reply:Cool post. Those rockets look like fun!
Reply:I flinched every time  Sure, I can fix it... I got a welder!!!
Reply:So I drag my rocket launcher around to all kinds of events. The kids love it. Last summer I discovered you can explode water bottle fairly easily with quite a dramatic effect even with the hand pump. So, being that it was the 4th of July my youngest brother and I decided to do a little "recycling" of our own. It was good for a laugh. They make the water bottles so thin it only takes about 100 psi to pop one. Yes to safety glasses and ear plugs. Happy 4th of July. Enjoy the video.