HAPPY NEIGHBORS
Keep you neighbors happy by not having your rockets land on their property. Rockets can take an unexpected turn while up in the air. Use more caution for larger and heavier rockets!
LOST IN TREES
I am happy to report that most of my rockets caught in trees have eventually come down. One took 3 weeks. It's really not worth risking injury climbing trees to recover rockets. Do not go near power lines to recover a rocket. Rockets are cheap to replace out of recycled materials.
SAFE PRESSURES
In the first prototypes, there was no pop-off valves. We had a few explode, and wow, it's sounds like a stick of dynamite. To prevent explosions, I installed 150 psi valves, then 125 psi, and now we have settled with 100 psi valves. We have not have bottles rupture yet at 100 psi, and it seems to be a safe level. Even with the lower pressures, there seems to be little effect in maximum altitudes. A bottle manufacture told me that they test the bottles to hold a threashold pressure of 150 psi. So, limiting pressurization for our rocket fun to only100 psi gives us a pretty good safety margin.
We have to realize that the bottle manufactures make millions of these 2 liter bottles, and they sample and test a very tiny percentage for quality.
DO NOT USE AS A GUN
Please remember DO NOT aim rockets to people, animals, and things that can be damaged. Use common sense. I've recorded speeds of these water rockets at 120 m.p.h. and faster when held horizonally!!! DON'T DO THIS!!!!
BLACK BOTTLE - BAD LUCK
One known solid black painted bottle left out in the hot sun was overheated. Lighter colors would be better, and more visible in the sky and for finding on the ground, or in the water.
WARNING SIGNS OF EXPANDING WEAK BOTTLE
Another indication of a weak bottle would be to see no increase in pressure, on the pressure gauge, while filling. For example, if you have the bottle at 60 p.s.i., and you are pumping air into the system, say 2 or 3 strokes on the bike pump, and the pressure gauge is not moving, and there is no indication of air leaking in the system, watch out. This rarely happens, but you should be attentive always when working around anything that has pressure.
ABORTING PRESSURIZATION
There may be reason for you to abort the launch. You may need to decompress the system that is air tight. If the rocket has high pressure, I recommend that you cover the rocket with a towel, jacket, or something, and then slowly turn the trigger mechanism COUNTERCLOCKWISE until air tight seal is broken. Let it bleed off slowly. However, the new launchers build in 1997, have a NEW bleed off valve, which is much more convenient.
DUCT TAPE "ROCKET MUMMY"
One method of making a rocket last a long time, and more explosion proof, was to cover the entire lower section of the rocket with duct tape, before adding fins.
This did work good, the only draw back was that there was not a "water fill window". We had to guess at the amount of water in the rocket. However, with the hyro-fill launcher system, the water seemed to automatically stop filling at the right time because of the water pressure at the locations we used. So, not being able to see the water level was not such a disadvantage as it might first appear to be.
The duct tape was wound in a spiral pattern similar to taping a bike handlebar. The tape could be wound in such a manner to provide a gap for a water fill window.
FILAMENT TAPE
This very strong tape could be used to reinforce the lower rocket section. It is clear enough so viewing the water fill level can still be visible.
Filament tape could be used by wrapping it completely around the bottle 1.5 to 2 times at several locations on the lower unit. This would limit expansion.
Recently, a measurement showed that a 2 liter bottle expands 5/16" in circumference when filled with 100 p.s.i.
BOTTLE EXPANSION MEASUREMENTS
This is just an idea to have a measurement tape around the bottle and watch how much it expands during filling. There might be some indications to a bottle about to rupture.
Maybe a permanent band, with a RED LINE, around the bottle that acts as an indicator. When the bottle gets old and starts to fatigue, a RED LINE on the indicator band shows the bottle is ready to retire.
"SOCKET ROCKET"
Imagine being able to convert a 2 liter bottle into a rocket in just a few seconds. This is a new concept of attaching fins and wings to a 2 liter bottle. It eliminates the need to use adhesives directly on the bottle. Adding fins is as simple and fast as putting socks on your foot.
Presently, I've been sewing a sock out of spandex material. It would be easier to find a commercially available sock for large people that would be large enough to slide over a 2 liter bottle.
The fins and wings are attached to the fabric in various methods, such as adhesives and/or sewing.
The roots of this idea germinated from trying to invent a process of adding a protective layer over the bottle, for additional safety, in case it would weaken and burst. The fabric would catch, or slow, potentially flying debris. Is anyone out there making Kevlar socks? ha ha
Lately, with the discovery of better glues, stryofoam fin material and better rocket designs, the "socket rocket" has been abandoned, but not forgotten.
VINYL COATED ROCKET
Another attempt to "explosion proof" a bottle was dipping the bottles, after completion, with fins attached, in a liquid vinyl dip solution. This was to add another layer of skin over the rocket. I also used a spray vinyl from an aerosol can. These materials as commonly used to cover the handles for tools.
CUSTOM MOLDED WATER ROCKETS
I had contacted one bottle manufacture who could make an extra heavy duty bottle, just for our application. There was also discussion about including fin and wing designs in the molds for the bottles. However, presently there are not enough sales to support buying a minimum order of a semi-truck full of rocket bodies.
USE ONLY WATER AND AIR
Do not use anything but water and air. Do not use flammable materials. Many components are made from Type 2 PVC plastic which will dissolve with solvents and flammable materials.