DY Water Rockets - Day 5 22.5.11

Post photos and videos of your rocket, launches and your onboard video or photos here. A wide variety of formats supported including attachments and embedded youtube.
User avatar
jerm
WRA2 Member
WRA2 Member
Posts: 39
Joined: Sun Sep 27, 2009 1:14 am

DY Water Rockets - Day 5 22.5.11

Post by jerm »

DY Water Rockets - Day 5 22.5.11
[youtube][/youtube]

Hi Everyone,

It was a good day and we where testing a lot of new things on the rocket. There is a new Gardena launcher release and this performed well. There is a new nozzle as a result of the Gardena release, this needs some work as the rocket didn’t fly straight until the air burst. The new presser chamber performed well and the new PET push out for the parachute did very well.

Enjoy the video.

DY Water rockets
DY Water Rockets
User avatar
Spaceman Spiff
WRA2 Member
WRA2 Member
Posts: 681
Joined: Sat Feb 24, 2007 11:06 am

Re: DY Water Rockets - Day 5 22.5.11

Post by Spaceman Spiff »

jerm wrote:DY Water Rockets - Day 5 22.5.11
[youtube][/youtube]

Hi Everyone,

It was a good day and we where testing a lot of new things on the rocket. There is a new Gardena launcher release and this performed well. There is a new nozzle as a result of the Gardena release, this needs some work as the rocket didn’t fly straight until the air burst. The new presser chamber performed well and the new PET push out for the parachute did very well.

Enjoy the video.

DY Water rockets
Looks like you're making really good progress.

Thanks for posting the update.
Spaceman Spiff
"What goes up, must come down"
User avatar
jerm
WRA2 Member
WRA2 Member
Posts: 39
Joined: Sun Sep 27, 2009 1:14 am

Re: DY Water Rockets - Day 5 22.5.11

Post by jerm »

Thanks!

Starting out there is a lot of testing and we are starting to get somewhere on the construction techniques and reliability of the rockets.

DY Water Rockets.
DY Water Rockets
User avatar
Spaceman Spiff
WRA2 Member
WRA2 Member
Posts: 681
Joined: Sat Feb 24, 2007 11:06 am

Re: DY Water Rockets - Day 5 22.5.11

Post by Spaceman Spiff »

jerm wrote:Thanks!

Starting out there is a lot of testing and we are starting to get somewhere on the construction techniques and reliability of the rockets.

DY Water Rockets.
How reliable has your parachute deployment system been? In the video it seems to work really well. Do you have any recommendations for someone looking to do something similar? I was using a system where the nose pops off but I wanted to make a side door deploy so that I could put a backup parachute in the area behind the fins where the bottle tapers. I thought I had a really good system but the parachute now snags on the fins and the rocket crashed both times I tried it. My theory is that I should make the shock cord longer and wind it around the chute to delay the opening. Do you have any suggestions? Thanks.
Spaceman Spiff
"What goes up, must come down"
User avatar
jerm
WRA2 Member
WRA2 Member
Posts: 39
Joined: Sun Sep 27, 2009 1:14 am

Re: DY Water Rockets - Day 5 22.5.11

Post by jerm »

Hi Spaceman Spiff

The deployment system has been reliable, I have tried a number of systems and to date the side deployment has suited my needs. It has slowly developed from issues that we have had and now I have not had a in flight failure for some time, however in saying this there has been issues during testing where the rubber bands have court on the Tommy timer and I have had an issue with the Tommy timer failing in flight where it just fell apart. They just don’t make toys to last anymore!

With the PET push out system this was development following system that used rubber bands however these perished after some time and there was not much power in there deployment. I also tried foam but there is much more power in the PET than the foam and the PET is lighter.

The new PET push out which is just a piece of bottle that is hot glued in place (be careful of the temperature of the glue)and this can pushed the parachute almost across my garage. The door is also PET plastic and I use gaffer tape to fix this to the rocket (I reverse this door so it springs open).

I have found that long chock cords can slow the deployment of the parachute. I have used plastic and cloth shuts and the cloth (old tent) opens much better as the air can get into the canopy quicker. I picked up a trick from how some reserve shuts in paragliders are packed where the last fold string in turned up to get the air started into the canopy. This makes the canopy open quicker.

My Tips
1. A robust Tommy timer
2. Watch the glue temperature when gluing the PET.
3. Reverse the door so it springs open
4. TEST, TEST and TEST!!!
DY Water Rockets
User avatar
thampson
Current WRA2 Dragster Speed & Distance Record Holder
Current WRA2 Dragster Speed & Distance Record Holder
Posts: 232
Joined: Wed Jul 16, 2008 8:19 am

Re: DY Water Rockets - Day 5 22.5.11

Post by thampson »

DY,

Nice flight, great to see the parachute working well and you were able to take the rocket home in one piece. :)

Seems we have a few WR enthusiasts in Sydney now :)

keep up the good work

-todd-
HHWRSA
Hornsby Heights Water Rocket Space Agency
http://wrocket.hampson.net.au
User avatar
jerm
WRA2 Member
WRA2 Member
Posts: 39
Joined: Sun Sep 27, 2009 1:14 am

Re: DY Water Rockets - Day 5 22.5.11

Post by jerm »

Thanks Todd,

Yes it is going well, I lost a lot of fins in the past (hot glue does not work on fins)and now I have not lost one for some time.

Well done on the record Todd!!!!
DY Water Rockets