Troubleshooting

Troubleshooting your AntiGravity Water Rocket

When you run across a problem with your 1-, 2-,  3- or 4-stage rocket, there is almost always something you can do to solve it. Here are some of the solutions that you can try.

1. The rocket doesn't go very high and the stages tip sideways before separating, or don't separate at all.

This is usually caused by low pressure in the rocket. If you are using a hand-powered bicycle air pump, you should be pumping about 70 pumps per 2-litre bottle (i.e 200 to 220 pumps for a 3-stage rocket. or 70 pumps for a single stage) before launching. Or if you are using an electric powered air compressor, you should have it set to provide 120 psi to the launcher hose, because it takes some extra pressure to move air through the thin filling hose.  When the rocket pressure relief valve starts whistling (this happens at about 82 PSI pressure), then you should launch the rocket by disconnecting from the pump or compressor.

2. The middle or upper stage lifts off by itself.

This is usually caused by the three interstage clips not being aligned inside the clip guides of the ring fin they are trying to hold on to. The clip guides (they look like 3 pairs of very thin fins around the ring fin) have a soft foam material in between each pair that the clips can grip onto and hold. If the clips are trying to grab onto the hard material of the fin, they will just slip and let go of the ring fin too soon.

 3. Air leaks out of the push-connector when I pump up the rocket.

This can be caused by an uneven surface or scratch in the thin plastic launcher hose. Remove the hose from the push-connect by pressing in the release ring and gently twisting and pulling out the hose. Then neatly cut off and discard about 1/2 inch (1.27 cm) of the thin hose, and re-insert the hose into the push-connect. The new smooth, clean hose surface should seal inside the quick connector much better.

4. One of the rods in the ring fin assembly broke and I can't remove it. How can I remove it?

To remove a broken rod, with one hand grip the ring fin, and use a pair of pliers to grip the base of the rod where it is inserted into the ring fin. Twist the rod radially and gently pull it out at the same time. The same technique applies if you are removing the other end of the rod from the nozzle arms. Then you can insert a new spare rod in its place.

5. The filling hose connector or interstage nipple is too difficult to insert.

Lubricate the filling hose connector o-ring or interstage nipple o-ring with a bit of Vaseline, silicone grease, or butter. This always works.

6  One of the rocket stages fell straight down instead of doing a slow belly flop fall.

This is caused by water that is still in the rocket bottle after ascent is complete. During descent the water runs to the front of the stage, weighing it down enough to cause a high-speed straight-down fall.  Use less water in that stage for future flights.