Hello and welcome to this video! If you
want to build an advanced water rocket and
you don't want to start all over again
after the first flight, we suggest
building a recovery system for your
rocket which brings it safely back to earth.
Let's begin with the basics!
A parachute  deployment mechanism, the most common recovery system for a water rocket
ejects the parachute at the right time.
That sounds pretty easy but in fact it
is one of the most sophisticated tasks
when building a water rocket. The system
has to be small, light and reliable. There
are numerous approaches for parachute
deployment mechanisms. In this video, we
show you how to build a mechanical
system based on a Tommy Timer. Tommy Timers can be found in windup toys which
are available in toy stores and on the
internet.
After removing the case you can cut off
all protruding parts of the timer using
pliers. You should also remove the
plastic handle from the main axle by
repeatedly clamping it in a bench vice. After that, bend the axle using two sets of
pliers. The modified timer will later be
the centerpiece of the system. You may
wonder why we use these mechanical
timers and don't work with electronic
systems. Well the answer is pretty simple:
Mechanical systems are way easier to
build and repair, are significantly
lighter and a lot more affordable when
compared to electronic ones. This is
especially important when a rocket
crashes and you have to build a new
parachute deployment mechanism. But luckily
this shouldn't be the case all too often
since the two systems we want to show
you in this video have already proven
the reliability with numerous flights.
The first system we want to show you is
called Phoenix 6. It's the latest
version of our Phoenix Parachute Side
Deployment Systems and is optimized for
rockets with a single large pressure
vessel.
For rockets consisting of multiple
pressure vessel segments we recommend
building a Phoenix Radial Deployment
System. This system was originally
developed by our colleagues from U.S. Water Rockets but we've adjusted and
optimized it for the use with a
lightweight mechanical timer. If you want
to skip the steps for building a Phoenix
6 System and jump to the tutorial about
the Phoenix RDS, feel free to do so. For
the construction of the Phoenix 6 Side
Deployment Mechanism you will need two bottles. It is necessary to use the same
bottle type you have already used for
your pressure vessel. Cut off the bottom
of one of the bottles using scissors and
remove the threat of the bottle with a saw.
Now you have to cut a big opening in
the cylindrical section of the bottle.
In this case the opening is about 10cm / 3.9"
wide and there should be about 3cm/1.2" left
to the lower edge. But of course your
case will need a nose cone. You can
either glue a half table tennis ball on
top with epoxy or you can use the nosecone
of a fireworks rocket for that.
Now take the second bottle and remove
both the bottom and the neck. The
remaining cylindrical section will be
separated in two equally large pieces.
One of these pieces will be the
parachute door. If you want to paint your
system, you can do this now. First, sand
and clean both the case and the door. We
recommend using plastic primer before
applying the paint. The spray paint can
be applied as soon as the primers is dry.
It is may be necessary to spray several coats.
After that you can cut two round base plates
out of a thin plastic plate. You
should be able to put the plates into
the system but they shouldn't be too
small and should remain in place
without any glue. After you have placed
the plates directly at the lower and the
upper edge of the opening you can glue
them in place using a hot glue gun.
Please be careful and don't use too much
adhesive. Now it's time to mount the
Tommy timer you have already modified at the beginning. All you need are three
small holes in the case located slightly
above the lower base plate. Put the bent
axle of the timer through the hole in
the middle and use a small cable tie to
fasten it. The parachute door which is
placed over the opening can be fastened
by using a rubber band. Just mount a loop slightly under the upper base plate on the case.
Now you can wrap the rubber
band multiple times around the system.
At the end, hook the rubber band over the
bent timer axle. To eject the parachute
you will need a spring. For that you can use a part of a thin walled plastic bottle.
You can attach the bottle piece with wire
on the case but you can also take the
whole cylindrical section and glue it in place with a hot glue gun. However, if you
use this method you have to watch out
that the parachute will be pushed out of
the opening and not to the side. The
door can now be attached with a rubber
band on the parachute. But before we
finish the construction of the Phoenix 6
Mechanism we want to take a look at
the Phoenix RDS. The good news is that it
consists of even less components than
the Phoenix 6. The most important
component is a thin but flexible plastic
cover. You can use a document cover or a
thin walled bottle section for that.
Mount the modified tommy timer at one
edge of the cover using two cable ties.
On the opposite edge. you can attach a
rubber band loop. For the next steps you
will need a rocket with multiple
pressure vessel segments. Wrap the cover around the connection between two
segments, then wrap the rubber band
around it and hook it on the timer axle.
Another rubber band attached to the
cover and the nosecone will ensure that the cover will be pulled away
when the parachute gets ejected.  The Phoenix RDS is now already on the same level as the Phoenix 6 System whose
construction we described earlier in
this video. The following steps are
identical with both systems. To prevent
the rubber band sliding over the bend of
the timer axle, glue a small cable
tie head with epoxy or super glue
directly at the bend.
Now you can hook in the rubber band once
again and wind up the timer - a few
seconds later the rubber band will be
released and the parachute ejected. Now the only thing you need to complete
the construction is a small trigger
which holds the timer in place until the
rocket launches. Luckily the construction
is fairly simple: You just need a big
cable tie! Cut the long part off so that
the remaining cable tie is only about
5cm/ 2" long. Now wind up the timer and place the trigger
underneath the small cable tie you used
to attach the timer, so that the timer
can't start running. Connect the trigger
to your launch pad and you are ready to
launch! But don't forget to attach the
parachute and the system to your rocket
first. If you want to learn how this
works, how you can build your own launcher
and how to build all the other
components for your water rockets, check
out our YouTube channel and our website.
We'll see you next time! :)
