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Build Your Own Jet Engine 148

Posted by michael
from the burning-down-the-house dept.
jgarland79 writes "Have you ever wanted your very own jet engine? Build one at home in your own garage. The guys over at www.garagejet.com have done just that. Their jet engine is made from an automotive turbo, spark plugs, and some scrap metal. I have made a mirror site here." We've had a couple of previous stories about a guy building pulsejet engines - the type of engine described above is a turbojet.
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Build Your Own Jet Engine

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  • by cheinz (714431) on Friday May 07, 2004 @09:57PM (#9090923)
    'Nuff said! ;)
  • Oh great, (Score:5, Funny)

    by demonbug (309515) on Friday May 07, 2004 @09:57PM (#9090928) Journal
    Now I'm going to have to start worrying about real rice rockets on the way home from work.
  • by hellmarch (721948)
    attempt to win the x prize. w00t
    • Re:now i can... (Score:2, Informative)

      by Anonymous Coward

      now i can... attempt to win the x prize

      Yes, you can attempt, but unfortunately you're going to fail....

      Both jet and rocket engines combine fuel with an oxidizer to make thrust. Jet engines, however, use oxygen from the air while rocket engines use another source of oxygen (liquid, compressed, or solid in some compound that'd burned to produce O2).

      The upshot is that you can't use a jet engine to get into outer space, only a rocket engine, because there's not oxygen up there for a jet engine to burn

      • Re:now i can... (Score:5, Insightful)

        by penguinoid (724646) <spambait001@yahoo.com> on Friday May 07, 2004 @10:24PM (#9091060) Homepage Journal
        The upshot is that you can't use a jet engine to get into outer space, only a rocket engine, because there's not oxygen up there for a jet engine to burn enough fuel to make enough thrust.

        Wrong! You *can* use a jet engine to go into space. You just need to accelerate to 11,000 km/h, the escape velocity (lower if you are at higher altitude, or just want to go into orbit). You can even go into space with a (really big) cannon.

        Your jet engine will come crashing down.

        And if you do reach space, you will be wishing that you did come crashing down.
        • Re:now i can... (Score:3, Informative)

          by RayBender (525745)
          You can even go into space with a (really big) cannon.

          But you can't go into orbit. Also, of you were to start from the surface of the Earth with several times excape velocity you will a) be vaporized by the atmosphere, b) likely be slowed down such that you don't ever reached space, c) killed by the deceleration forces.

          A while back this topic came up over a lunch discussion and I did some looking into it. Check this link [nuclearweaponarchive.org] for some interesting background. As best I can estimate the lid made it up to abo

          • Re:now i can... (Score:1, Informative)

            by Anonymous Coward
            A scramjet will. Go NASA!
            • A scramjet will. Go NASA!

              Actually, no. A scramjet - if it is ever made to work properly for more than 5 seconds - will accelereate you to something like Mach 12 and 100,000 feet. That is not space, nor orbital velocity. From there you have to use a rocket.

          • I had a professor in college who claimed that there's no such thing as 'deceleration'; it's acceleration in a negative direction. GOD I hated that and never did quite grasp the concept. I mean seriously, how do you accelerate negatively? Jeez that guy pissed me off.
            • Simple. Acceleration is a change in velocity (which is speed AND direction), not an increase in speed. Basically, if you're moving, you're pulling Gs. When that number of Gs changes, you're accelerating. Negative acceleration (reduction in Gs) is what is commonly known as deceleration.
              • Close, but:
                Basically, if you're moving, you're pulling Gs.

                No, you only experience g forces (NB small g, big G is the Gravitational constant) when you either

                A) undergo acceleration,or

                B) experience gravitational attraction.

                Of course without an external reference you can't tell which of those it is either.

                Ignoring gravity if you're pulling g you're being accelerated, and yes the scalar component of the acceleration may be negative.

        • Wrong! You *can* use a jet engine to go into space. You just need to accelerate to 11,000 km/h, the escape velocity (lower if you are at higher altitude, or just want to go into orbit).

          The major difficulty is that turbojets don't work well with supersonic air going into them. You'd probably want some kind of engine which could change from reheated turbojet to pure ramjet (and back again). Having engines gives you rather more options comming back down again (including being able to taxi off the runway, so
  • Excellent! (Score:5, Funny)

    by AndroidCat (229562) on Friday May 07, 2004 @10:00PM (#9090941) Homepage
    Combined with the Slashdot articles on Build Your Own Cruise Missle [slashdot.org], I'm good to go!
  • Two slashdottings for the price of one!
  • Another one... (Score:5, Interesting)

    by simcop2387 (703011) on Friday May 07, 2004 @10:02PM (#9090950) Homepage Journal
    Another site that shows you some of the steps in building a gas turbine engine (also known as a jet engine) this one uses a turbo charge, probably not quite as good though

    http://asciimation.co.nz/turbine/

    he also uses it to cool beer.

    http://asciimation.co.nz/beer/
  • Please help with bandwidth! Please right click on the links, and choose save target as. These videos are in real audio format. If you do not have real player you can get it for free HERE [real.com]

    I don't see how that would help but I bet it goes down faster thatn a crashing jet airplain.
    • Please help with bandwidth! Please right click on the links, and choose save target as. These videos are in real audio format. If you do not have real player you can get it for free HERE [real.com]

      I don't see how that would help but I bet it goes down faster thatn a crashing jet airplain.


      I don't see how that would help but I bet your Karma goes down even faster.
  • by airbatica (743048) on Friday May 07, 2004 @10:04PM (#9090963)
    These guys are amateurs compared to Mark Nye of Nye Thermodynamics. I realize the page is a little old, but homebuilt gas turbines aren't exactly high tech till you get up to the FADEC systems of commercial jetliners

    http://www.nyethermodynamics.com/

    Off topic: Ooo... lets slashdot the server to oblivion. It's got MOVIES!
    • Haha. Yeah, and the one he built to melt snow off of driveways is way too heavy and dangerous to use without bolting it to something heavy.
      "Honey, seen any snow yet?"
      "No, not yet." ...
      "OK, dear, it's snowing."
      "Yay!"

      *click.... click*
      *WHOO000SH!*
      "AIIIIIEEEEEEEEEeeeeeeeee...........!"
  • by Anonymous Coward on Friday May 07, 2004 @10:04PM (#9090964)
    If you like small engines, take a look at 5bears.com [5bears.com] -- he's made a turbojet (centrifugal compressor and turbine) and a turboprop, complete with microcontroller-based starter/fuel system, in addition to a couple of radial engines, a CNC mill, and a homebuilt spotwelder.
  • by demonbug (309515)
    I bet you could move a shopping cart at greater than 3 ft/min with that thing.
  • Well.. (Score:1, Troll)

    by mrsev (664367)
    They are going to die! The only good point is that it will be quick!
  • Anyone have the videos in a standard format?
  • Inexpensive (Score:3, Interesting)

    by acceber (777067) on Friday May 07, 2004 @10:14PM (#9091007)
    A real jet engine, say the one used on a F-16, runs around the figure of $350,000 USD...Finding used parts at the junk yard will yield much less cost. A complete engine can typically be built for less than $300 USD.
    It's interesting how price isn't an obstacle when it comes to building your own jet engine. The average person may think that it's impossible but these guys have proven that you don't need high tech equipment, just a couple of basic tools to be able to build something so out of the ordinary.
    This would definitely be a source of inspiration for those budding innovators and inventors.
    • Re:Inexpensive (Score:4, Insightful)

      by DerekLyons (302214) <(moc.liamg) (ta) (retawriaf)> on Saturday May 08, 2004 @12:21AM (#9091559) Homepage
      It's interesting how price isn't an obstacle when it comes to building your own jet engine. The average person may think that it's impossible but these guys have proven that you don't need high tech equipment, just a couple of basic tools to be able to build something so out of the ordinary.
      These guys haven't proven that you can build your own jet engine, they've proven you can modify a turbosupercharger into a gas turbine. The Really Hard Part is the turbines, which they *bought*, as opposed to being made.

      It's cool, it's semi impressive, but it's not what it's hyped to be.

      • Good God! *They* didn't prove it, Frank Whittle did in the 40's!
      • This looks like a lot of fun but here are the problems I see with it.

        1. I'm pretty sure a turbo charger isn't designed to tolerate the heat we're talking about.

        2. With #1 in mind, Do you really want something spinning at 100k RPM's that's not designed to handle that heatload...

        I'm just having visions of this thing getting up to speed, a fin blade heating up and deforming, thus causing the whole turbo shaft to come apart in rapid succession. Then watching the person standing next to the thing getting tur
  • Do they use the frozen chicken launcher test method or do they use more historical (but less modern) live chicken?
    • Will little frozen chicken McNuggets work? That turbo is rather small to swallow a big bird.

    • Actually, the chicken launcher launches *thawed* chickens at something like 200mph. IIRC it was developed first to test canopies and windscreens- jets came later. Rolls Royce borrowed it from the US, but didn't know about the thawing step... resulting in a 'famous' anecdote in the annals of jet turbine development history. Can anyone substantiate this story? I asked a RR blade engineer if it was true- he said yes, but even so, the story is hard to believe.
      • Dunno about RR and frozen chickens, But back in the 70's my Grandfather was part of a crew at GE Aircraft Engines in Cincinnati who would go up into the cooling towers in the old 800 building and collect pigeons for "bird tests".

        They used CO2 extinguishers to get em down fast, (confused the birds more than freezing them) and would collect dozens a week for engine FOD testing. Had to make sure none of them were actually frozen for some strange reason. (laughs)

        Obviously GEAE can't do it like that anymore, b
    • Do they use the frozen chicken launcher test method or do they use more historical (but less modern) live chicken?

      Dead, but not frozen, chickens are fired at aircraft to ensure that they will survive birdstrikes.
  • mis-engineering? (Score:3, Interesting)

    by grepistan (758811) <duncan_c@noSPAM.tpg.com.au> on Friday May 07, 2004 @10:18PM (#9091026)

    I like the drill being used as an oil pump, but what happens if some bright spark hits the reverse direction button?

    I hope those chaps have good home & contents insurance!

  • by j3ll0 (777603) on Friday May 07, 2004 @10:21PM (#9091046)

    When building an engine that will potentially operate at over 1000 degrees Celsius, be sure to build frame out of wood.

    • When building an engine that will potentially operate at over 1000 degrees Celsius, be sure to build frame out of wood.

      The hottest stuff comes out the business end, not the support points.

      Not the best setup, I admit, but I presume this is not long-term durability testing. All they need is a good insulator between contact points. Or maybe a liquid helium cooling system with lots of piping design engineering hours.
  • by Recoil_42 (665710) on Friday May 07, 2004 @10:23PM (#9091057) Homepage Journal
    Just a side note, the New Zealand government recently shot down bruce's $5,000 cruise missle project. read about it here. [interestingprojects.com]

    Very sad, i was looking forward to its completion.
  • by jamie (78724) <jamie@slashdot.org> on Friday May 07, 2004 @10:26PM (#9091072) Journal
    Kids, if you build your own jet engine, then unlike the nice fellow in the videos, please wear ear and eye protection.

    Especially if you plan on titling one of your videos "Ooops! Forgot to make sure the fittings were tight!"

    Jeez...

  • More Power! for my riding lawn mower. grr grunt grr grunt grr grunt.
  • 555 timer? (Score:4, Informative)

    by kd5ujz (640580) <william@ramSLACK ... com minus distro> on Friday May 07, 2004 @10:44PM (#9091172)
    These guys are charging $20 for the 555 chip. These things go for around $0.90 at radio shack. At first I thought it was the entire assembly, but then I saw the assembly for $50.
  • by CherniyVolk (513591) on Friday May 07, 2004 @10:45PM (#9091174)


    Let's see, super chargers are ungodly expensive....
    Adding turbo or even replacing turbo, out of this world....

    But! Two 300 dollar jet engines welded to the side of your Ford Escort!?!?!?!? Francine Dee! Here I come!
  • by Dread_ed (260158) on Friday May 07, 2004 @10:46PM (#9091185) Homepage
    "We've had a couple of previous stories about a guy building pulsejet engines - the type of engine described above is a turbojet

    We just invented a new one...serverjet! That is where fire shoots out of the drive bays of a server so fast that the whole thing flies across the room!!

    Sometimes I just think yall pick random servers to destroy. Kinda like that guy from the Jerk who flips through the newspaper and then just pops his finger down on a person and then he kills them. Likewise, you probably put in a topic to Google and hit "I'm feeling lucky!" Whoever the unlucky site is gets the slashdotting!

    I can feel you laughing from here.
  • by dvd_tude (69482) on Friday May 07, 2004 @10:48PM (#9091192)
    They used an automotive turbo, etc. It was the "jet car" episode.

    As I recall it didn't generate very much thrust.

    (didn't RTFA)
  • Pod race! (Score:4, Funny)

    by AtariAmarok (451306) on Friday May 07, 2004 @10:48PM (#9091193)
    Once you'd built one of these, build another. Then tie a lawn chair in between, and start 'em up! Should be a real blast.
  • since it doesn't provide thrust or torque. Propane-powered whistle would be more like it.
  • by azav (469988)
    Anyone have Non Real versions of the videos? Some MPEG 4 files maybe?

    Thanks
  • Welding (Score:1, Informative)

    by Anonymous Coward
    The welds on those pipes were some of the worst I've ever seen. I'm surprised it didn't blow up!
  • by Tablizer (95088)
    It probably started out as an attempt to improve a blow-dryer for a chronically late person.
  • by Boyceterous (596732) on Friday May 07, 2004 @11:46PM (#9091401)
    back in the mid 1980's. He was a mech engineer and used the company machine shop to fab the parts. He said it got up to about 200 lbs of thrust - until the turbine blades flew out the back end ( he used aluminum instead of titanium) - luckily he only got slightly injured.
  • Laserjet (Score:3, Funny)

    by Rhodnius (749829) on Friday May 07, 2004 @11:56PM (#9091443)
    Pulsejets, turbojets... what's the big deal? They invented Laserjets years ago. Can get one of those for $400 or less, and the laser just runs on electricity, doesn't need fuel...
  • Next these guys will duct tape 10,000 model rocket engines to a tin can and send it into orbit as a homemade sputnick! oh wait John carmack has got this one covered!!! http://www.armadilloaerospace.com/n.x/Armadillo/Ho me
  • Let me sum up. Old turbo, propane tank, metal tube, power steering pump used as an oil pump driven by a hand drill, 6 inchs of flame shooting out the end of the tube and the whole thing is mounted on a couple of painted 2x4s. Tell me, which piece will fail first?

    I love these homemade projects, but good lord, this one is 2 steps away from a stay in the burn ward.
  • by barjam (37372)
    RCs have used jet engines for years. They can be had (the engine, not the RC) for about 3k. They feature computer control/startup etc.

    Pretty cool stuff.
  • why is the original site and the mirror still up ??? /. defeated by a meanie weenie server !!! Probably they have jet propelled apache.
  • by cmholm (69081) <cmholm@noSPAM.mauiholm.org> on Saturday May 08, 2004 @01:40AM (#9091789) Homepage Journal
    First, full points to the builder for moving beyond the web research stage and getting his hands dirty. For those wanting to play with turbines, but want a design that's ready to slap onto a r/c model, some gents in the Netherlands implemented a cheap design using a smaller turbocharger and an empty Gaz propane camping stove cartridge back in '99. The original links to this design are harder to Google nowadays, now that the designers have gone commercial.

    You've seen the movie, now buy the book: Gas Turbine Engines for Model Aircraft by Kurt Schreckling [amazon.com]

    What Kurt's design looks like [virgin.net] when built per plans.

    Gas Turbine Builders Association [gtba.co.uk]

    Photos [gtba.co.uk] from the GTBA of various completed motors, note the small sizes.

  • by NewtonsLaw (409638) on Saturday May 08, 2004 @01:41AM (#9091795)
    The guy who built the cruise missile and those pulsejets (me) also built a turbo-turbine back in 2001 and documented it here [aardvark.co.nz]

    Then I added the afterburner [aardvark.co.nz]

    And if you want to see a really cool turbine-powered gokart [nickhaddock.co.uk] check out Nick's website.

    More pulsejet/turbojet links and things here. [aardvark.co.nz]

    Now we're all really keen to enter the chinese version of full metal challenge [yin-long.com]!
  • Actually we used a turbojet made from a car turbo in my undergraduate mechanical engineering energy conversion lab.. Needless to say these thing get efficiency values around 10% to 12% or much less( I thin I remember a value 3% in my lab report). If I can recall my gas turbine design class, normal aircraft turbojets are closer to 60% or even 80%...
  • I've been following the progress of home buyilders of similar turbines for at least the last 5 years. Many modellers are using these designs in actual flying model aircraft, and have been for some time. How is it news?

  • Is a good feeling to hear of people building their own engines it's about time to all of us attempt to go farther in faster then will build a day ambition to go into space

    By the way I love commenting on slashed by with my Dragon NaturallySpeaking dispelling is an average and I'm sure you can understand what I'm saying he was not what I said that was not what I said but that was what I said to buy bye-bye goodbye bye-bye goodbye so long sea later sea later I'll see you later there that's better
  • Real jet engines have a Turbine Inlet Temperature sensor. These guys seem to be aware that they don't want to get the turbine too hot, because hot metal is weak metal and overheated turbines can shatter at high speed.

    And I would NOT walk around perpendicular to the axis of the tubine while it's running! Jesus Christ, at least put the thing in a 55 gallon drum or something!

    • Most people building turbo-turbojets *do* have at least a turbine outlet temperature sensor.

      And, if you think a 55-gallon drum is going to do *anything* to reduce the damage or danger produced by a grenading turbine wheel then you've obviously never seen one let-go or calculated the energy levels involved!

      • When I was in the Marines, we used 1/4" steel blast shields for running up APUs and generators. A regular 55-gallon drum may not be much, but it's damn sure better than nothing. These small turbos probably turn at extremely high RPMs, but they don't have much mass and they are enclosed in a heavy casting already.

        Watch the videos. These guys are walking around the device in t-shirts and blue jeans, without even the most basic hearing or eye protection!

  • by andyr (78903) <andyr@wizzy.com> on Saturday May 08, 2004 @04:49AM (#9092215) Homepage Journal
    Check out the Wikipedia [wikipedia.org] featured article on Jet engines [wikipedia.org]
  • My car is getting old. It's current value is down to about $450, so it's getting to the point that the only upgrades that are worthwhile are the ones I build myself.

    This would also let me build entirely new skills like jet-assisted parallel parking.
  • ...does not a good thrust turbine make.

    The reason is an automotive turbocharger is designed to provide a lot of pressure at a modest flow rate. It does this with particular sizes of intake and exhaust turbines (amongst other things). A car engine (compared to a jet engine) ingests air slowly, so higher pressure at this slower rate is what is needed to turbocharge a car engine. In a jet engine, you need a much higher flow rate, which is much better suited to a different design of turbine.

    What you end u

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