Introduction: Water Rocket 2-Stage Mechanism

Picture of Water Rocket 2-Stage Mechanism

This mechanism was developed to provide automatic staging of multi-stage water rockets. This mechanism will release a sustainer with a standard 9mm Gardena nozzle when the booster stops producing thrust.

The following tutorial describes how to build the staging mechanism. It should be used more as a guide rather than an exact step-by-step procedure as it is likely you will not have access to the identical parts used here. Feel free to substitute components as you see fit.

NOTE: Read the tutorial carefully including the notes at the end as there are important bits of information that you will need.

Step 1:

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This stager is designed to work with a standard 9mm Gardena nozzle. If you don't have one already, you will need to make the nozzle first. Here's how: Making a Gardena nozzle.

Step 2:

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Here are the materials you will need.

- 5mm Clear vinyl tubing (or similar) :
- 1 x Gardena quick connector
- 3 x springs from 3 other Gardena quick connectors
- 2 x plastic pen tips
- 2 x pins
- 1 x bottle cap
- length of wire
- length of T8 FTC tubing (70mm & 35mm) (or similar size tube)
Example: ( )
- Electrical tape
- Epoxy glue

- Drill and 5mm drill bit (drill bit needs to match tubing OD)
- Sandpaper
- Scissors
- Craft knife
- Pliers

Make sure that the Gardena quick connector you are using will not slide into the FTC. There is a flange on the quick connector just behind the thread. The flange diameter should be bigger than the FTC diameter. Some cheaper brand quick connectors are slightly narrower and could potentially slip inside the FTC.

Step 3:

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Cut two lengths of the T8 FTC. One should be ~70mm long and the other ~35mm.

When you cut these out, you need to make sure that the edges are as square as possible. Use a piece of paper wrapped around the outside and mark along the edge. Carefully cut along the lines. If the edges are not square then the sustainer will not sit straight on the booster. You can use scissors to cut the FTC along the line.

Step 4:

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Roughly cut the FTC piece off with a craft knife, and then trim to the marked line with scissors.

Step 5:

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Cut the smaller FTC tube length ways with a pair of scissors.

Step 6:

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Remove the orange collar from a Gardena quick connector by inserting 3 strips of PET plastic underneath the collar's locking tabs, and then pulling back on the collar.

Remove the spring and re-assemble the collar making sure you have the white locking tabs in place. You will need 4 of these springs altogether so you can remove these from old quick connectors. Make sure the springs are identical in size.

At this point test to see if the sustainer nozzle locks all the way into the quick connector. If it doesn't, you can modify the quick connector as shown here: Launcher Fix

Step 7:

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Sand the internal hole of the Gardena quick connector to allow the epoxy to grip better.

Step 8:

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Put a piece of Blu-Tack, plasticine or modeling clay on the workbench and stand the Gardena connector on it's end (orange collar pointing up) so that the Blu-Tack blocks the central hole.

Mix up some epoxy and carefully pour it through the open end. Pour enough epoxy in so that it is about 5-10mm deep. It's better to use the stronger epoxy rather than the 5 minute stuff.

Let the glue fully cure for 24 hours.

Step 9:

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If the cap is the kind with a removable seal then remove it from the bottle cap and cut a hole in it as shown. The bottle cap may not have a removable seal or may be one of the type C caps then you don't need to do this step.

Step 10:

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Assuming the outside diameter of your tubing is exactly 5mm, drill a 5mm hole straight through the top of the cap.  It does not need to be exactly on center.

NOTE: The tube needs to be a snug fit in this hole. You should not be able to slide the cap freely on the tube. If the hole is too big, get a new cap and drill a smaller hole.

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Now use the same drill bit and drill a hole in the epoxy glue of the Gardena quick connector.

Step 12:

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Cut about a 220-230mm length of the clear tubing with a pair of scissors.

Find an old plastic ball point pen that has a conical pen tip. You may need to look through a number of them, as some have small ridges on the inside. You may also find other small plastic cones as part of other components. As long as it is small enough to fit in the end of the tubing then it should be good. The conical section needs to have smooth internal walls to allow the valve to seal properly.

Step 13:

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Push the cone section into the tubing as far as it will go. This is easy to do if you grip the end of a pop rivet or something similar in a vice and then push the pen tip over it.

NOTE: It is important to have the pen tip securely pushed into the tubing. If it is loose, it may get pushed out under pressure.

Step 14:

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Cut the head off a pin with a plastic round head, or alternatively find a ball bearing of the right size and make sure it fits inside the pen tip cone section. It should be big enough not to fall through the smaller hole of the cone.

Heat another pin and push it through the plastic walls of the cone so that the round pin head can move up and down, but cannot fall out.

Step 15:

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Push the pin through, cut it with a pair of wire cutters a couple of mm from the pen tip, and bend it with pliers to stop it from falling out.

Step 16:

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You can wrap a couple of wire loops over the tubing and tighten with pliers.

Step 17:

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This is how the non-return valve should look.

Step 18:

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Wrap a length of tape around one end of the longer section of FTC. Here we are using glass strapping tape about 10mm wide. Wrap enough of the tape until the outside diameter of the tape is the same as the orange collar diameter.

Step 19:

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Cut out two slots as shown in the FTC body. These should be wide enough to let the tubing move freely inside them. Cut them elongated so the tubing has room to move as the spring compresses.

NOTE: The location of these slots will depend on how your springs sit. I assemble the stager first without the tubing and then draw on the outside of the FTC where the holes need to go. The upper hole should be as high as possible and the lower hole should be as low as possible. This allows the tubing to sit more vertically in the cap and the quick connector giving a better seal.

Step 20:

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Insert the free end of the tubing through the quick connector and pull it all the way through until the non-return valve is sitting snugly inside the quick connector against the epoxy.

Thread 3 of the springs completely onto the tubing, with the first spring pushed all the way up to the flange of the quick connector and the fourth spring should be only partially threaded. Let the tubing emerge out the side of the 4th spring.

Now insert the springs and tubing into the FTC body, allowing the tubing to emerge from the bottom hole. This is a little fiddly but not difficult. After all the springs are inserted, make a loop in the tubing and rethread it back through the upper hole and back down the center of the FTC body.

Pull the tubing out as far as it will go (the loop will tighten) and insert the tubing in the top of the bottle cap.

You can now push the cap into the FTC body. The caps and FTC we use fit snugly together. Your FTC may be a little bigger or cap smaller, so at this point you can wrap a bit of tape around the cap to give a tight fit. You may need to try a few caps otherwise, until you find one that works well.

Step 21:

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For the next step we need to widen the free end of the tubing so it cannot come out of the cap. For that we use the plastic tip from another pen. This is a very common type of pen, with a metal tip fitted in a plastic adaptor with the ink straw inserted from the other end. Pull out the metal tip with pliers, and remove the ink straw. You'll be left with the hollow plastic adaptor. This is a nice size for the tubing, and the tapered and makes it easy to insert into the tubing.

Alternatively you can use something like a round glass bead with a hole in it and push it into the end of the tubing.

Step 22:

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You can again use the pop rivet or similar in a vice to hold the pen tip.

Step 23:

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Push the tubing over the pen tip until the end of the tubing is level with the end of the pen tip.

Step 24:

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Now wrap a couple of loops of wire over the end to prevent the pen tip from being pushed out under pressure.

Step 25:

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Push the tubing back through the cap until the pen tip is pushed up snugly against the hole in the cap. The tubing loop will loosen again.

Screw the cap onto the booster bottle and tighten. Now push the FTC body down over the cap until it rests on the bottle flange. This will help support the sustainer during acceleration.

NOTE: There needs to be quite a bit of friction between the cap and the FTC body so that the spring does not push the cap out.

Step 26:

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Take the smaller piece of split FTC and slip it over the rolled up tape at the top end of the FTC body. Tape this down with the electrical tape. Make sure you tighten the tape really well and wrap it several times. You also need to pay special attention to the alignment of the split FTC so that it is not at an angle to the FTC body.

Step 27:

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NOTE: The next step is very important, and it helps to get someone to help you.

Place the nozzle into the stager and push down the inner part of the quick connector compressing the spring until the flange rests on top of the FTC body.

While holding down the inner part of the quick connector, slide the orange collar all the way up until the nozzle is locked. Now wrap electrical tape around the orange collar where it overlaps the short piece of FTC. What you are trying to achieve is to attach the orange collar to the split FTC.

Once you tape it down firmly, (use a few wraps) you can release the nozzle, and the inner part of the quick connector should spring out again.

There will be approximately a 10mm gap in the split FTC. This gap cap be used to place a locking tab in the stager. (see below)

(This image was taken from our other stager and is why the lower tape is white in this image)

Step 28: Measuring Spring Tension

Picture of Measuring Spring Tension

Because there are so many varieties of springs and quick connectors it is difficult to predict how much force your springs will give.

You will need to measure the spring force that opens your stager:
1. Place a nozzle into the stager and then place the nozzle on a kitchen scale.
2. Zero the scale
3. Press down on the stager until the mechanism locks.
4. Now slowly start raising the stager until the nozzle just starts moving.
5. Take a reading on the scale at that point.

You should get a reading of 800grams or more. If it is much less than that, you may find that the stager fails to open in flight. (We found out the hard way). This means your sustainer needs to weight at least 800 grams to keep the stager locked. This is not unreasonable for a small sustainer considering it may weigh 200 grams with 600mL of water. If the fully fuelled sustainer weighs less than than, you can still use this stager with a locking tab. (See below)

Step 29: Notes

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Adjusting the Spring Tension

You may find that you need to adjust the spring tension of the stager. This can be achieved by trimming the bottom of the FTC body and pushing it down against the bottle flange again. This will increase the spring tension.  Trim a couple of mm at a time.


1. You may find that the dimensions of your FTC are such that the inner part of the quick connector does not move freely. You can apply a coat of silicone grease on the inside of the FTC body and the springs to help it move better. If this does not work you may need to get different FTC from another manufacturer.

2. Though the clear vinyl tubing says it is rated to 50psi, the actual burst pressure is a lot higher. It will easily handle 200psi+.

3. If you find that your nozzle does not lock properly into the stager, you can fix it by modifying the quick connector.

4. What if the sustainer is too light to keep the stager locked? See 'locking tab' below.

5. What if I can't get T8-FTC? - FTC is commonly available and can be ordered on line, but you could try making your own tubing by rolling up and gluing PET plastic together. As long as the dimensions of the tube are correct you don't need to use FTC.

6. In order to use this stager as shown here, you will need to construct the booster in such a way that it has a bottle neck at either end. This can be achieved either by splicing the bottles together or joining them with a Robinson coupling.

7. The sustainer will normally need to be supported with additional bracing to prevent the sustainer bending over and snapping the staging mechanism. This is normally required for most staging mechanisms anyway.

8. The stager could be damaged if the booster lands directly on it. The sustainer support can be used to protect the stager.

9. The springs you used should all be the same diameter so that when they are inside the FTC body they don't thread themselves into one another.

10. If you don't like the idea of using tape to attach the split FTC, you can try gluing it. Tape allows you to pull the stager apart if you need to.

11. If you find there is a tiny leak around the flexible tubing, it will likely stop once pressure is applied.

Using the Stager

To use the stager, simply fill the booster with water and place it on the launch pad. Fill the sustainer with water and push the sustainer nozzle into the stager and let the sustainer's weight lock the stager.

Locking tab

If the sustainer is not heavy enough, you can insert a locking tab in the space between the collar and the inner part of the quick connector. This is in the gap of the shorter piece of FTC. Tie this locking tab with a string to the launch pad. When the rocket launches, the locking tab will get pulled out, but acceleration will keep the sustainer in the locked position until the booster runs out of thrust.

The locking tab is just a small block of plastic or wood that is just thick enough to fit between the collar and the flange on the quick connector.

Step 30: How It Works & Video Tutorial

Picture of How It Works & Video Tutorial

How It Works

If you wish to find out how this staging mechanism works, then full details are available here:

This tutorial is also available as a video tutorial:

Full flight report with video and photos is here:


dchall8 (author)2017-12-05

While this I'ble is very good at guiding the construction (which is genius in the use of hardware store parts), I had no vision of how the thing worked. There is a lot of "do this and do that," but nothing explaining how the parts work together. After reading all the way through I finally got to the end with a link to an external website where the operation was explained in a few paragraphs. Now when I go back to the top I have a context as to what you're doing, why, and how the parts work together to separate the 1st stage from the 2nd stage. Here's a suggestion to describe how this mechanism works.

This water rocket stage release mechanism was developed to provide automatic staging of multi-stage water rockets. On the launch pad the mechanism locks the two stages together by the weight of the second stage pushing against a quick-release connector for a garden hose. The 2nd stage weight compresses a spring inside the mechanism. There is a flexible air pressure transfer tube which allows the two stages to be pressurized at the same time. Water and pressure leaks are prevented by the arrangement of valve parts inside the mechanism. In flight when the 1st stage booster stops producing thrust, the rocket approaches a weightless state where the spring pushes the stages apart. When the parts separate the interlock releases the stages which releases the pressure in the second stage, thus allowing the 2nd stage to fly higher. After release the staging mechanism remains attached to the 1st stage booster and can be reused after a parachute recovery (not included in this Instructable).

As for the parts used, you have the experience and have better insight into the durability of this, but I would think a thin-walled PVC would be more sturdy than the FTC tubing you use. Of course you can't cut PVC to open up the diameter like you do with the FTC, so there is that.

Anyway this is a very clever use of simple parts to make an amazingly complex separation system.

dchall8 (author)dchall82017-12-05

And now that I think a little more about it, would parts of this system make a much better ground launch pressurization and fly-away nozzle for a 1 stage rocket? Again, not having tried it, it seems like the smaller nozzle you use would work better than the 1/2-inch open bottle neck nozzle.

dchall8 (author)dchall82017-12-05

As I continue to reply to myself, I found several sources for the Gardenia Launcher. Good stuff.

tanis10 (author)2017-05-04

i did it

JosephC42 (author)2015-09-08

Are the springs necessary to the separation? Or could you use a plastic substitute or just continue without them?

JonathanM173 (author)JosephC422016-03-31

The springs act in a reverse function of their original purpose, so, Yes, the springs are needed to help push the coupling apart. The use of a locking pin on the launch pad is required only if your spring set is a little too strong.

YaënD (author)2015-03-31

just waooh !

MatthewH6 (author)2015-03-22

Nice job on the instructable, but I find all of the information somewhat confusing what with all the product names and such. Could you simplify the information into english please?

stumlad (author)2014-12-22

You could substitute the mechanism used in those non-pressurized spray bottles as an alternative (and easier) for the non-return valve.

sbgfsdb (author)2014-06-06

a mi tambien

sbgfsdb (author)sbgfsdb2014-06-06

tu eres un noob

sbgfsdb (author)2014-06-06

a mi tambien

seejianshin (author)2014-01-15

can this separation device function more than 2 stages?

(since it is gravity powered....)

Tbirdfisher (author)seejianshin2014-04-26

I believe so , but am not fully positive.

THErocketies (author)2012-08-09

Nice rocket but what is T8 FTC because i searched for it everywhere. Is there a alternative for T8 FTC. If there is plz respond.

air.command (author)THErocketies2012-08-09

Look for fluorescent tube covers at lighting stores. It's a polycarbonate tube used for protecting fluro lights.

Here is an example:

U.S.CouchPotato (author)2012-05-28

about how much would it cost to make on of these rockets?

about $20 dollars if you don't include the electronic parachute ejection. There are many cheaper ways of deploying a parachute.

U.S.CouchPotato (author)2012-05-28

also i would like to know if you can reuse this mechanism or if you have to make a new one after every launch

You can re-use it as many time as you like, unless the rocket gets stuck in a tree where you can't get to it. :)

Frans van Dijk (author)2010-08-16

Nice work. For water rockets and related toys: see Google patents: there are a few hundred of them. Multistage water rockets: 2804823 Multiple unit projectile Jablansky 1957 2829491 Two stage liquid fuel rocket Teague 1958 2927398 Multiple stage rocket Kaye 1960 3049832 Two stage rocket Joffe 1962 3091052 Multiple stage projectile Ryan 1963 3292302 Multi stage model rocket Estes 1966 3550313 Multistage reaction toy Pippin 1970 3943656 Two stage rocket with pressure responsive means for frictionally engaging second stage Green 1976; others: 2003/0071077 10_254_987 Fluid slug launcher Panzarella 2003 2006/0225716 10_908_976 Rocket launcher toy Lapointe 2006 2007/0012305 11_160_954 Toy Water Rocket Launcher Williams 2007 279539 Air projectile Chamberlain 1883 616410 Toy boat Crawley 1898 650633 Toy cannon Cooper 1900 672889 Toy Conant 1901 990228 Toy gun Cohrs 1911 1033094 Target air gun Fuda 1912 1079200 Toy Wilde 1913 1229129 Springgun Peacock 1917 1248507 Pop gun Leveber 1917 1394551 Arial toy projectile Hitt 1921 1588040 Pump Moore 1924 1612794 Toy Bender 1927 1639602 Toy parachute Gay 1927 2017778 Toy airplane projector gun Vido 1935 2345243 Aquatic figure and apparatus Eakin 1944 2375607 Toy rocket projecting gun Wulfert 1945 2398391 Toy airplane Orkin 1945 2409653 Toy rocket gun Amdur 1946 2426610 Rocket launching gun Hopkins 1947 2449147 Toy Samuels 1948 2449187 Projecting apparatus Walters 1948 2478224 Toy projectile Armstrong 1949 2484320 Toy projectile Stevens 1949 2521135 Toy rocket Stark 1945 2559458 Toy parachute and projector therefor Orr 1951 2563969 Toy spring rocket launchers Skinner 1951 2568475 Toy para rocket Vaughan 1951 2583463 Toy compressed air pistol Boulet 1952 2587687 Toy gun Beyers 1952 2588184 Toy socket bomb Walsh 1952 2589977 Water gun Stelzer 1952 2594627 Jet propelled device Endicott 1952 2621441 Whistling toy aerial projectile Worden 1952 2624281 Projectile McNally 1953 2630654 Parachute toy Poen 1953 2642289 Toy rocket Gersmehl 1953 2675642 Toy rocket Coleman 1954 2700337 Liquid propellent rocket Cummings 1955 2714269 Ornamental beaded necklace Charles 1955 2718093 Parachute toy Payne 1955 2718094 Explosive rocket toy McInnes 1955 2725868 Air gun Foster 1955 2732657 Jet driven aerial toy Krautkraemer 1956 2733699 Rocket toy Krinsky 1956 2742734 Guided misslie toy Maras 1956 2748529 Toy rocket and parachute Swan 1956 2751711 Toy projectile and means to propel same Greenwood 1956 2759297 Partitioned toy rocked Lewis 1956 2787192 Semi automatic repeating rocket launcher Stam 1957 2792669 Balloon Jackson 1957 2793590 Practice projectile Brandt 1957 2820321 Toy airplane Kuhn 1958 2826001 Self propelled model submarine Presnell 1958 2841084 Toy rocket Carlisle 1958 2867153 Launching control device Hirsch 1959 2879624 Toy jet missile Benson 1959 2918751 reaction propulsion toy Johnson 1959 2924041 Balloon Jackson 1960 2934041 Booster mechanism Ayers 1960 2957272 Action toy savings bank Berzack 1960 2959889 Toy embodying whistle operated by gravitational outflow of water while the toy is in the air Gausewitz 1960 2991782 Toy Ayala 1961 2993297 Toy rocket Bednar 1961 3002314 Rocket toy Brottman 1960 3014308 Rocket and launcher therefor Parris 1961 3025633 Rocket launcher Kaye 1962 3025635 Rocket toy balloon Walters 1962 3040522 Rocekt engine control system Williamson 1962 3046694 Jet propelled toy arrangement Holderer 1962 3046966 Toy air compressor rocket launcher Butler 1962 3121292 Rocket toys Butler 1964 3125955 Toy rocket motor Estes 1964 3174501 Valve and valve mounting De See 1965 3188768 Toy projectile which converts to space platform during flight 1965 Boswell 3218755 Toy missile with delayed opening device Quercetti 1965 3230707 Steam generator 1965 Rothmayer 3301246 Compressed air rocket propelling Wolfe 1967 3303643 Method and structure for supplying and confying fluid in a reaction chamber Beardsley 1967 3406480 Toy vehicle Joffe 1968 3436074 Fluid driven elevating amusement device Knox 1969 3490235 Passively regulated water electrolysis rocket engine Grant 1970 3510980 Propelled toy arrangement and method Pippin 1970 3635162 Practice bomb Lohkamp 1972 3740896 Jet powered vehicle Glass 1973 3740896 Jet powered vehicle Glass 1973 3785083 Teaction toy arrangement and method Pippin 1974 3937191 Rocket launcher including remotely releasable pin latch Green 1976 3962818 Reaction toy arrangement and method Pippin 1976 3965611 Directionally stable reaction fluid propelled carrier missile with fluid sealed movable retention and release wall Pippin 1976 4038776 Rocket toy Filipeli 1977 4076006 Toy rocket with pneumatic launcher Breslow 1978 4223472 Toy projectile launching device Fekete 1980 4295290 Toy projectile Boswell 1981 4345729 Thrust units Barter 1982 4411249 Toy glider with pneumatic launcher Fogarty 1983 4664631 Surrogate weapon for weapons effects signatures Pederson 1987 5188557 Toy rocket apparatus Brown 1993 5381778 Pressurized toy rocket with rapid action release mechanism D'Andrade 1995 5399251 System for generating hydrogen and oxygen Nakamats 1995 5415153 Pressurized air water rocket and launcher Johnson 1995 5433646 Water gun launching water grenade Tarng 1996 5538453 Air pressure toy rocket launcher Johnson 1996 5819717 Launcher for a toy projectile Johnson 1998 5839940 Pressurized gas water rocket and launcher therefor Ensmenger 1998 6093076 Water propelled toy torpedo Street 2000 6321737 Toy rocket launcher Johnson 2001 6347623 Toy projectile launching assembly Kownacki 2002 6398613 Pump powered toy with an on board pump Rehkemper 2002 6532948 Toy rocket set Grichen 2003 6820840 Hydrogen powered toy rocket utilizing hydrogen from the electrolysis of water Lund 2004 6945495 Hydrogen powered toy rocket utilizing hydrogen from the electrolysis of water Lund 2005 6957526 Pressure actuated toy rocket sysem Lin 2005 7252079 Safe air pressure launched toy rocket system and method of entertaining Walker 2007 Des 254918 Toy airplane Harranek 1980.

that comment is huge did it take like an hour to write that

ferret421 (author)DontShoot2622010-08-28

yea wtf what is all that

Frans van Dijk (author)ferret4212010-08-29

Ferret421, it is a list of 120 or so patents related to water rockets, I downloaded from the Google site. To find them: 1 start up Google Patents. 2 select the option advanced patent search. 3 type in the number of the first mentioned patent, in this case 2829491 in the field Patent number. 4 The patent Two stage liquid fuel rocket by mr Teague in the year 1958 (and others) will appear. Start reading. It's amazing what you can find on this site. Have a nice day, Frans van Dijk

What you posted is spam. Removed.

Cubie2 (author)Frans van Dijk2011-03-18

Thanks for the info but we probably didn't need you to post all of those here. :P It just takes up space.


It was.

jid4611 (author)DontShoot2622010-09-22

no it was probably copy and paste

23wy (author)2011-04-09


woodstockbirdy (author)23wy2012-03-12

Really? Don't make one words posts, its annoying.

chowchow95 (author)2011-09-12

how many metres will this rocket go?

air.command (author)chowchow952011-09-12

Very much depends on what pressure you use. This particular one shown here should go to around the 350 foot mark at max pressure.

singhtarandeep15 (author)2011-01-06

Please let me know how to produce pressure above 100psi, so that I can launch my rocket as I have already made it.
Please reply me as early as possible

Taraandeep Singh

You'll need a launching mechanism. I simply used a zip-tie launching mechanism mounted on a 1/2" pvc pipe and embedded a tire valve on the other end with a lot of epoxy. It took me about 3 hours to make once I had a design that included stabilizing the whole rig. If you have a multi stage rocket, you defiantly want a full bore nozzle for your booster, which the zip-tie method allows for. Otherwise a garden hose quick release valve system would be a lot easier to make.

From there you just attach a bike pump and with a little elbow grease, you've got yourself 100+psi.

Thanks for the reply.
my water rocket just take off from its launching pad and falls down. According to me the water should fall on the ground perpendicularly(according to newton's third law) to raise the rocket at the height. If I am right then please let me know how to do the same. But if I am not correct then please guide me what to do and how to do?

Please reply as early as possible

Are you using 1/3 water, 2/3 air in your rocket?
Are you using fins?
If you don't have enough pressure in your rocket your rocket won't go very high and would flop like you described. If you had pictures of your rocket and launcher it would be easier to analyze your problem.

singhtarandeep15 (author)2011-01-26

Please let me know which part have you used to throw the releasing water out perpendicular to the ground (part used at the mouth of the sustainer bottle).

singhtarandeep15 (author)2011-01-06

Please let me know how to generate 110psi pressure.

Also please let me know what amendment has to be made in the booster for correct adjustment of the pressure valve.

Please let me know all this as early as possible as I have already made rest of it.

Hi there,

Pretty much any bicycle pump can get you over 110psi. How much pressure were you after?

I am not sure what you mean in your second question. Could you please elaborate a little more?

air.command (author)2010-10-01

Hi There, I'm not sure I understand specifically what you are asking. If you want to know how it launches, that's described in the links above.

Is it just a model? No, we have now flown it quite a few times. Here are some of the more recent flights using this stager with a more powerful booster:

I want to know if there is any alternative for Garden quick connector as I am not able to get this from the market..

Unfortunately this particular design does depend on it. There are other staging mechanisms based on different principles. Try searching for the "crushing sleeve" mechanism. Alternatively you can buy the quick connectors on line for a couple of dollars.

Please let me know how to produce pressure above 100psi, so that I can launch my rocket as I have already made it.
Please reply me as early as possible at my email

singhtarandeep15 (author)2010-11-25

hey, it is interesting..But I want to know if there is any alternative for Garden quick connector as I am not able to get this from the market..

Mudbud (author)2010-10-28

wow, this is amazing! I am going to build this on the weekend!!! I have all the tools, now I just need the parts... hmmm Am I the only 13 year old building this?

singhtarandeep15 (author)2010-10-09

What is the use of garden quick connector in our daily life(its application)?

kelseymh (author)2010-10-01

You should post this as a top-level comment, so the author of the Instructable notices it.

meatlord (author)2010-08-13

Nice work G-man. Great design!

air.command (author)meatlord2010-08-13

Thanks Damo. This one was a fun build. :)

kelseymh (author)2010-08-09

This is an outstanding Instructable! The level of detail, and photos, are really impressive. The very idea of a multistage water rockets is just a bit mind-boggling. I noticed that you sort of integrated the quick-release valve build into this one. Did you consider writing it up separately and just making a cross-link?

About This Instructable




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