--- In water-rockets@yahoogroups.com, George Katz <air.command@...> wrote:
>
> Hi DL,
>
> Sorry I missed your post from a while ago, I was cleaning out my
email and noticed it. The T8VTT looks really good. Thanks for sharing
the design. I have a number of 6' T8 tubes sitting around and would
like to experiment with them. I might have a go building a similar
deployment mechanism based on your one.
>
> Have you flown it?
>
Hi George

Glad the assembly gave you some good ideas.  It's kinda the outgrowth
of several things I've been working at.  The extending plunger design
is something I've slowly improved over time,  The syringe triggering
grew out of an idea Richard W. once mentioned.

Made the Chute yesterday from a 1'square section of plastic shopping
bag.  I just used some magic tape to hold tucks in the 4 corners;
forces the square into a dome shape.  Braided fishing line is secured
to the darts as shrouds.  Takes like 5 minutes to make that Chute.

Was a tricky plan to get it all to fit inside T8 and still use a
minimum length of extra fuselage.  I tried to make the frame barely
longer than the altimeter. I'm guessing the 6' T8 is about the perfect
length for these wrockets by the way.  I used about 5' for the
pressure vessel this time.  2 gift cards cut in half become 4 fins

  (-;

Haven't launched it yet... was running sims on Clifford's site, and a
full bore 21mm nozz was showing the highest apogee so I am gathering
up materials to build that internal release design launcher.  I figure
I can trial it with that and a Gardena nozz to see if the sim has it
right.

dl

Hi Alex,

Just the servo section which does the gripping / releasing, I can do
the rest. Would also need the size of the o-rings, and inner tube you
use, incase I need to replace them.
No hurry.

What would that run me?

And can you take a bank money order from the U.S.A.?

Thanks for your time,
>

George,

Way cool picture. Very well done.

Maybe we should start a photo competition this year :)

Richard.


--- In water-rockets@yahoogroups.com, "George Katz" <air.command@...>
wrote:
>
> Here is a picture from our last weekend's launch day:
>
>
http://ph.groups.yahoo.com/group/water-rockets/photos/view/6329?b=4&m=f&\
> o=0
>
<http://ph.groups.yahoo.com/group/water-rockets/photos/view/6329?b=4&m=f\
> &o=0>
>
> The panorama was composited in Photoshop from a video sequence as the
> rocket pitched over at apogee.
>
> Enjoy :)
>
> - George
>

I flew Estes pyro rockets as a kid, and I've been back in that hobby for about
ten years.  Once
someone showed up at one of our launches with a home-made 2-liter rocket and
launcher.
It only reached 5-6 m altitude. The nose separated, but the chute failed to
open. It nearly hit
me. I was not impressed.

The cost of motors keeps going up, and I am not about to start mixing my own
fuels. Even
the good deals on bulk packs are disappearing. While searching for good prices,
I typed
"Water Rocket" out of frustration. Wow!  I had no idea of the things that are
possible and
being done!

I'd like to try building and flying water rockets. Most of the sites I've seen
so far assume some
basic familiarity with standard water rocket building techniques. Even the
launcher plans are
hard to make sense of if you haven't seen one up close. The links page for this
group lists
quite a few sites with advanced projects (not to mention the porn sites), but 
I'm having a
hard time finding sites for beginners.

I need directions or plans for getting started.

----- Original Message -----
From: "Daniel Kirk" <dk54321@...>

Daniel wrote:
  The links page for this group lists
quite a few sites with advanced projects (not to mention the porn sites), but 
I'm having a
hard time finding sites for beginners.

I need directions or plans for getting started.

----------------

Hi Daniel.  welcome to our 'lil passion.

I'm sure Jon M will post links to his Bristol Launcher... it's simply the slider
cap from a sports water bottle becomes the launcher and the nozz is the cap part
with the innerds removed.  Becomes a self releasing launch system at around
105psi.  w/ 11.5mm nozz.

A really simple launcher to make:  get a Gardena or other quick couple hose
release for water hoses.  Mount it to some stand that will let air to it.  Add a
pull string to pull on the release collar.  Get the other end that couples to
the release; the one with female 3/4" garden hose threads.  Heat the threads
with a heat gun or boiling water and force-thread it onto a plastic pop bottle.
Offers a manual release and a 9mm nozz that you can make smaller by adding
inserts.

If you drill a 1/2" hole in a bottle cap you can make many parts by attaching
1/4" pipe threaded fittings.  Some suitable washers, teflon tape and those 1/4"
nuts for making electric lamps are also needed.  One launcher is made by
mounting the stem for an air hose to the cap and the air hose release to a
stand(add pull string etc)  This one would be used for higher pressure
wrockets...maybe 300psi.  (also make pressure filler cap by adding a tyre stem
for bike tubless rims or a schraeder fitting that has pipe threads)

enjoy

dl

I suggest that you start with a quick-connect type of launcher. It's easy to make, doesn't require any exotic glues and piping, and the quick-connect should be buyable in most hardware stores.
The main part is a gardenhose quick-connect fitting. I've been using this one: Gardena 
Fit a hose with a valve to it, and you've got a launcher!

The nozzle for the bottle(s) is a bit more laborious. You have to find a way to put the male-fitting on your rocket. You might be able to find a male-fitting that screws right onto a soda-bottle (don't count on it!), or you can modify it.
Paul Grosse has a full plan on his site. He buys a big fitting, and glues it to the bottlecap.
I've been using another approach: I cut away the threads and trim the excess untill the fitting fits INside a bottlecap. This leaves the nozzle with a rim at its base. Now i cut a hole in the bottom of the bottlecap just large enough for the nozzle to be fitted from the inside, with the rim keeping it. The rubber-washer from the bottlecap can be used as a seal. The cap then screws right onto the bottle.

No glue, no modifications to the bottles (which is always a weak point in rocket systems), only a knife/saw/sandpaper is required for tools.

Good luck

Christian

--- In water-rockets@yahoogroups.com, "Daniel Kirk" <dk54321@...> wrote:
>
>
> I'd like to try building and flying water rockets. Most of the sites I've seen so far assume some
> basic familiarity with standard water rocket building techniques. Even the launcher plans are
> hard to make sense of if you haven't seen one up close. The links page for this group lists
> quite a few sites with advanced projects (not to mention the porn sites), but I'm having a
> hard time finding sites for beginners.
>
> I need directions or plans for getting started.
>

 Edit:

Checkout AirCommand. They made their nozzles nearly the same a i do, and they have a very nice description complete with photo-series.

One of the few differences is that they're using a brass female-fitting, i just got a standard plastic one. I've tested it to 10bars (~140 psi) with no problems at all - except that it took some skill with a bicycle-pump to get to that pressure...

Hi Daniel and welcome.

I am more inclined to suggest you start with a cable tie launcher rather than a gardenia type - I know I did. 

Good instructions are found here http://www.smoke.com.au/~ic/cable-tie.html.  Twisting bolt launchers are also very simple and extremely effective and reliable.

The reason I suggest you go this way is that you don't need to do anything to the bottle neck.  Once you have your launcher built (and you can do it with parts from a plumbing or irrigation shop) you can put any size bottle rocket on it and launch it.  No fiddling around cutting holes in bottle cap lids.  Plus, the full bore launches take off with tremendous acceleration. :-)

I have links on my site that might help you along too.  http://www.myspace.com/damohart.

Have fun.

Damo

Hi Daniel,

Welcome to the hobby. All the guys suggestions are very good and which
system you end up using will mostly depend on what you have available
on hand. You will most likely end up experimenting with them all.

A lot of the stuff you have learned over the years with pyro rockets
is directly applicable here so you are way ahead of a lot of people
who start out fresh.

Parachute deployment is probably the trickiest to get reliable enough.
  And there are as many solutions to the problem as there are
rocketeers. One of the things you will need to get used to coming from
pyro rockets is that you design everything to survive wet conditions
as inevitably there is spray from launching, spills during filling etc.

It's best to start off simple with a single bottle and a simple
launcher and then go from there.

Good luck and if you have questions about any details there are plenty
of people here that are more than happy to give you a hand.

- George


--- In water-rockets@yahoogroups.com, "Daniel Kirk" <dk54321@...> wrote:
>
> I flew Estes pyro rockets as a kid, and I've been back in that hobby
for about ten years.  Once
> someone showed up at one of our launches with a home-made 2-liter
rocket and launcher.
> It only reached 5-6 m altitude. The nose separated, but the chute
failed to open. It nearly hit
> me. I was not impressed.
>
> The cost of motors keeps going up, and I am not about to start
mixing my own fuels. Even
> the good deals on bulk packs are disappearing. While searching for
good prices, I typed
> "Water Rocket" out of frustration. Wow!  I had no idea of the things
that are possible and
> being done!
>
> I'd like to try building and flying water rockets. Most of the sites
I've seen so far assume some
> basic familiarity with standard water rocket building techniques.
Even the launcher plans are
> hard to make sense of if you haven't seen one up close. The links
page for this group lists
> quite a few sites with advanced projects (not to mention the porn
sites), but  I'm having a
> hard time finding sites for beginners.
>
> I need directions or plans for getting started.
>

Thanks to all for the tips and the links. I'd been digging through my search
results, and I still
wasn't sure what held the rocket on the launcher, or how it was released. After
examining
this page, it finally clicked:
http://polyplex.org/rockets/launcher/cable1.htm

Time to make plans and start gathering materials!

nt

--- In water-rockets@yahoogroups.com, "Daniel Kirk" <dk54321@...> wrote:
>
, it finally clicked:
> http://polyplex.org/rockets/launcher/cable1.htm
>
> Time to make plans and start gathering materials!
>

Great Fun!

Got to give Clifford a big hand of applause, BTW.  He's the guy that
got us into a group in the first place.

Amyways, You may find  yourself building several kinds of launchers,
as time goes forward. Each offer certain advantages and constuction
possibilities.  I think Nozz size and fin design tends to cause me to
build a new one.  I maybe have 5 or 6 kinds.  (oops forgot to finish
Paul G's style,  Plan to try CA or epoxy instead of solder on that.)

One thing I'd recommend is to have an abort valve and a guage at the
pumping end of the hose (if you want a guage).  The valve allows you
to depressure if something is amiss.  I've seen stands with the gauge
attached, but you should be many meters(10-15) away from there.

Also a nice upgrade is to replace a pull string with a 10cc syringe.
(Pnumatic Release)  Use a length of small diameter tube and a push
button (or other) valve to feed it air.  The syringe extends to pull
the release when fed air.  Kids love to play tag and trip over strings
(as do my big feet}; and antsi folk can pull a string too early, they
will have it prestetched- the button makes them have to pay more
attention.

Adding a pressure relief valve(s) to your outfit, can have 2 nice
functions.
1> Safety: especially if you are using a gas supply system(use preset
kind).
2> Released gas can be directed to a syringe(adjustable kind).  Nice
when you want to trial variations against the exact same pressure, or
not use a button valve.

Enjoy now

dl

when i get to my other 'puter I'll try to post links to JonM and DeanW
launchers.

No problem! Unfortunately Yahoo has no setting to allow
only un-moderated members to post links, so we moderators
must remember to occasionally check them. Setting the whole
list to moderators-only would remove its usefulness. If you
notice another spam attach, feel free to remind us.

I should go through my ancient set of links and clean out the
dead ones at least - I didn't know anyone was still using it (Hi
Mike!).

Clifford Heath.


On 07/04/2008, at 1:00 AM, Daniel Kirk wrote:

> nt
>
>
>

when i get to my other 'puter I'll try to post links to JonM and DeanW
launchers.

http://www.orgsites.com/va/bristolwaterrockets/

http://www.et.byu.edu/~wheeler/benchtop/poppy.php


For anyone not already familiar with these friends, please enjoy what more they
offer.

As to using a Gardena system, I did a page dedicated to what little inroads
towards helicopter deploy.  Near the bottom of that page shows how I used that
kind of nozz.  Several have already mentioned how to build similar systems.

http://wrockets.trib-design.com/index.php?project=DAVIDL&page=helio

Let me again mention about using a female threaded Gardena nozz.   It's just too
simple.  Happens that 3/4" garden hose threads and pop bottle (and many other
plastic container) threads are the same diameter, but different in pitch.  When
you carefully heat the Gardena part it can be fitted to a pop plastic pop bottle
using a only a little extra care and a fairly heavy hand..  I've foud glass
bottles that use similar threads... these would make a very good mold for
modifying the Gardena part.

HeHe

dl

Hay everyone,
OK I am sort of new in the soda bottle rockets. I have built a couple
and feel that I am ready to try new things; however I do have a few
questions:

1, Parachute deployment systems: Is there a better one over another?
2, Parachute: Is there a formula for size verse's weight? Just do not
know how big the chute needs to be. I use 2 liter and 24 oz. bottles.

Thanks for all your help.

Ron

I have had very good success with mounting a Tomy Timer on the side
of the wrocket and using it to hold a folded parachute on the outside
with a rubber band.  It's not the lowest drag option but it is
simpler than popping a nosecone or pushing a parachute out of a
payload section.

Pat

--- In water-rockets@yahoogroups.com, "George Katz" <air.command@...>
wrote:
>
> Hi Ron,
>
> Great to hear you are continuing development.
>
> On Parachute Deployment:
> There are two concepts to consider.
> 1) How and when you detect the best time to deploy. This is the
trigger
> mechanism.
> 2) How you go about mechanically getting the parachute out.
>
> With the trigger mechanism you have a number of choices. You can
try to
> sense the environment as to when the rocket reaches apogee
(typically
> not trivial) or base it on a timer.
>
> I always suggest timer based deployment because:
> a) You can get a pretty accurate measurement of when your rocket
will
> reach apogee from a simulator.
> b) It is simple
> c) It works regardless of the orientation or spin of the rocket, or
> whether it flies in an arc.
> d) Does not have to be highly accurate as you have a couple of
seconds
> to play with around apogee where the rocket is traveling relatively
> slowly for the parachute to open.
> e) Easily adjustable as you change your rocket parameters.
>
> You can choose Tommy timers (mechanical) or electronic timers.
>
> How you get the parachute out will depend on your preference. The
> typical options are nosecone popping off or side deployment. They
both
> have their advantages and disadvantages. We tend to use the side
> deployment method as we have other things like cameras and
altimeters in
> the nosecone and we want a steady platform for those on the way
down.
> Not so easy if they are in the nosecone and it pops off.  But
generally
> you will want some sort of spring mechanism to get the parachute
out.
> Air pressure on pop-off nosecones is an issue if the rocket
continues to
> fly in an arc and so you want to make sure the spring is strong
enough
> to over come this. Experiment with rubber bands, springs, springy
> plastic, soft foam etc.
>
> Some tips:
> If you want the parachute to open right at apogee, set your time for
> deployment a little bit before, as it takes a few moments for the
> parachute to fully open.
>
> Make your shroud lines and shock cord really strong to prevent the
> parachute from ripping off if deploys at high speed.
>
>
> Here is a good link for calculating the size of a parachute:
> http://my.execpc.com/~culp/rockets/descent.html
> <http://my.execpc.com/%7Eculp/rockets/descent.html>
>
> The red formula will give you the size. Most of the numbers in it
are
> constants so just plug those suggested values in.  You should
probably
> aim for 3-5m/s descent rate. This is a good range for survivability
> without excessive drifting in the wind.
>
> Hope that helps
>
> Cheers
>
> - George
>
> You probably want to aim at around
>
> --- In water-rockets@yahoogroups.com, "rlgreen54" <rlgreen54@>
wrote:
> >
> > Hay everyone,
> > OK I am sort of new in the soda bottle rockets. I have built a
couple
> > and feel that I am ready to try new things; however I do have a
few
> > questions:
> >
> > 1, Parachute deployment systems: Is there a better one over
another?
> > 2, Parachute: Is there a formula for size verse's weight? Just do
not
> > know how big the chute needs to be. I use 2 liter and 24 oz.
bottles.
> >
> > Thanks for all your help.
> >
> > Ron
> >
>

Want to thank George and Pat for their help, and advice. This will
give me some thought as to how it all works. For this old man (body
only) mind is still a kid lol, so it will take me some time to try
this information and put it to good use. The web that George sent
looks like it will help me on the size of the Parachute will need to
be. Good starting point. I hope to stay intouch, and hope some day
able to help someone else. Again thank you.
Ron



--- In water-rockets@yahoogroups.com, George Katz <air.command@...>
wrote:
>
> I also should have added Chemical Deployment in the timer category.
I'll let others cover the advantages/disadvantages of those.
>
> - George
>
> ----- Original Message ----
> From: George Katz <air.command@...>
> To: water-rockets@yahoogroups.com
> Sent: Friday, 11 April, 2008 9:53:17 AM
> Subject: [water-rockets] Re: Questions about Parchutes
>
>                 Hi Ron,
>
> Great to hear you are continuing development.
>
> On Parachute Deployment:
> There are two concepts to consider.
> 1) How and when you detect the best time to deploy. This is the
trigger mechanism.
> 2) How you go about mechanically getting the parachute out.
>
> With the trigger mechanism you have a number of choices. You can
try to sense the environment as to when the rocket reaches apogee
(typically not trivial) or base it on a timer.
>
> I always suggest timer based deployment because:
> a) You can get a pretty accurate measurement of when your rocket
will reach apogee from a simulator.
> b) It is simple
> c) It works regardless of the orientation or spin of the rocket, or
whether it flies in an arc.
> d) Does not have to be highly accurate as you have a couple of
seconds to play with around apogee where the rocket is traveling
relatively slowly for the parachute to open.
> e) Easily adjustable as you change your rocket parameters.
>
> You can choose Tommy timers (mechanical) or electronic timers.
>
> How you get the parachute out will depend on your preference. The
typical options are nosecone popping off or side deployment. They
both have their advantages and disadvantages. We tend to use the side
deployment method as we have other things like cameras and altimeters
in the nosecone and we want a steady platform for those on the way
down. Not so easy if they are in the nosecone and it pops off.  But
generally you will want some sort of spring mechanism to get the
parachute out. Air pressure on pop-off nosecones is an issue if the
rocket continues to fly in an arc and so you want to make sure the
spring is strong enough to over come this. Experiment with rubber
bands, springs, springy plastic, soft foam etc.
>
> Some tips:
> If you want the parachute to open right at apogee, set your time
for deployment a little bit before, as it takes a few moments for the
parachute to fully open.
>
> Make your shroud lines and shock cord really strong to prevent the
parachute from ripping off if deploys at high speed.
>
>
> Here is a good link for calculating the size of a parachute:
> http://my.execpc. com/~culp/ rockets/descent. html
>
> The red formula will give you the size. Most of the numbers in it
are constants so just plug those suggested values in.  You should
probably aim for 3-5m/s descent rate. This is a good range for
survivability without excessive drifting in the wind.
>
> Hope that helps
>
> Cheers
>
> - George
>
> You probably want to aim at around
>
> --- In water-rockets@ yahoogroups. com, "rlgreen54" <rlgreen54@ .>
wrote:
> >
> > Hay everyone,
> > OK I am sort of new in the soda bottle rockets. I have built a
couple
> > and feel that I am ready to try new things; however I do have a
few
> > questions:
> >
> > 1, Parachute deployment systems: Is there a better one over
another?
> > 2, Parachute: Is there a formula for size verse's weight? Just do
not
> > know how big the chute needs to be. I use 2 liter and 24 oz.
bottles.
> >
> > Thanks for all your help.
> >
> > Ron
> >
>
>
>
> <!--
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>
>
>
>
>
>       Get the name you always wanted with the new y7mail email
address.
> www.yahoo7.com.au/y7mail
>

Thanks Mike,
Lot of sites to go over, and absorb. But it will keep me busy.
Thanks again,
Ron

--- In water-rockets@yahoogroups.com, Mike Passerotti
<mikepasserotti@...> wrote:
>
>
> Try these to start:
> http://members.aol.com/hayhurst1/h2orocket.htm
> http://www.sonic.net/~rci/rocket/Deploy.html
> http://polyplex.org/rockets/links.html
> http://polyplex.org/rockets/
> http://polyplex.org/rockets/mousetrap.html
> http://www.geocities.com/rocketroos/recovery.htm
> http://madrocketscientist.tripod.com/Waterrockets/id10.html
> http://www.scoutingmagazine.org/issues/0611/a-redy.html
> http://wwong.homestead.com/rockets.html
>
> The simplest is to have a fall off design.  The most complex is to
have electronics deploy.  I hope you find a chute system.  I'm
working on several also.
>
> Mike Passerotti
>

Hi,

----- Original Message -----
From: "rlgreen54" <rlgreen54@...>
>
>1, Parachute deployment systems: Is there a better one over another?

Ya, one that works.  George K.  did a really good coverage towards timers.   I'd
add you can also bias the timer by how you make it start up.  You could just
have a pin that arrests some toy motor... pull the pin by the rorcket launching,
or I used a syringe/plunger assembly to release the timer as the fuselage looses
pressure(this is also a very good starts towards a camera trigger).

Another method is usng an airflap to detect when a rocket slows down.  It can be
a 'real time' deploy.  They are usually a delecate'mousetrap' to rig and get
working, but are VERY DEPENDABLE in the best of designs.  Air motion holds a
flap or vien down as the rocket ascends, but when the air motion slacks the flap
is free to move  Used only on rockets that go straight yup and stall..  If you
get some plan in your head, you can use the blower end of a vacuum cleaner to
test and trim it.

>2, Parachute: Is there a formula for size verse's weight?

You can also test your own... weigh a rock,tie your chute to it and throw it up.
Use stopwatch to measure what comes down how fast.  The fat light rocket should
fall slower than the rock of the same weight.  Use the smallest chute for less
drift, use a the biggest for'hang time'.

Recovery systems best reflect the need at hand.  Are you saving a camera or
Altimeter?   Is HangTime needed to win a contest etc.

Hi,

----- Original Message -----
From: "rlgreen54" <rlgreen54@yahoo.com>
>
>1, Parachute deployment systems: Is there a better one over another?

Ya, one that works. George K. did a really good coverage towards timers. I'd add you can also bias the timer by how you make it start up. You could just have a pin that arrests some toy motor... pull the pin by the rorcket launching, or I used a syringe/plunger assembly to release the timer as the fuselage looses pressure(this is also a very good starts towards a camera trigger).

Another method is usng an airflap to detect when a rocket slows down. It can be a 'real time' deploy. They are usually a delecate'mousetrap' to rig and get working, but are VERY DEPENDABLE in the best of designs. Air motion holds a flap or vien down as the rocket ascends, but when the air motion slacks the flap is free to move Used only on rockets that go straight yup and stall.. If you get some plan in your head, you can use the blower end of a vacuum cleaner to test and trim it.

>2, Parachute: Is there a formula for size verse's weight?

You can also test your own... weigh a rock,tie your chute to it and throw it up. Use stopwatch to measure what comes down how fast. The fat light rocket should fall slower than the rock of the same weight. Use the smallest chute for less drift, use a the biggest for'hang time'.

Recovery systems best reflect the need at hand. Are you saving a camera or Altimeter? Is HangTime needed to win a contest etc.

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Hi all - It has been a long time for me and I am now only getting back
into the swing of things.
I needed a good reliable switch to detect low pressure within the
rocket chamber. This little device seems to be quite reliable and I
have just posted some pictures of it under groups Photo - Trevor's new
TDD - LP Switch  ---  http://ph.groups.yahoo.com/group/water-
rockets/photos/browse/7a3d?c=

I use this to determine when to get ready for the parachute deployment.
Normally I have 1 second delay after the TDD registers the chamber is
empty. I also use it to fire second stages immediately it registers,
thus the stage will fire while the rocket is still thrusting by inertia.

I hope someone else may be able to use the design.
Trevor Hannam