This blog covers the day to day progress of water rocket development by the Air Command Water Rockets team. It is also a facility for people to provide feedback and ask questions.

Tuesday, May 26, 2009

Acceleron V stager testing

We've updated our main website with more details and photos of the Acceleron V build. There is short video that shows a couple of the pressure tests of the staging mechanism.

There is still lots to do before the next NSWRA launch. We're currently working on the parachute deployment mechanisms. We decided to use two of our existing parachutes for the booster so we will save some time there.

Wednesday, May 20, 2009

A little bit of pyro

We bought our 10 year old son a bigger pyro rocket for his birthday this year. He wanted something a little bigger than the Thunderbee he has flown several times on a 1/2A3. We bought him the Praetor from Suburban Rocketry.

Slowly over the last few weeks he actually built most of it himself, with a little help to get things lined up from dad. He did learn quite a bit about how a pyro rocket gets put together and the different materials and construction techniques needed compared to water rockets. He also learned quite a bit about the painting and extensive sanding process. It was just as much interesting for me to see how pyro rockets are put together. He chose the following colour scheme and spray painted it also mostly himself:

We had some decals from old model planes so we put those on to give the rocket a bit more character. We're hoping to launch it this upcoming NSWRA launch event on a C6-5.

Monday, May 18, 2009

Staging mechanism assembly

This week we have been continuing with the staging mechanism of the Acceleron V booster. We've also made the non-return valve that fits inside the long PVC pipe. The valve was adapted from the old Acceleron booster that was mounted in a bottle cap.

More information and photos of the build can be found on the Australian rocketry forum here:

It hasn't all been smooth sailing though. After test assembling the base plate in the launcher with the actual booster segments fitted with their nozzles we discovered that the central mechanism couldn't go down far enough to lock into the mechanism. Not wanting to machine up a whole new central nozzle, we decided to put a thick plastic washer underneath it on the base plate, and using somewhat longer screws to hold it all in place was enough to resolve the issue.

The other issue we had was while trying to fit the hose on the end of this central nozzle we found it a little difficult, so we decided to machine down the hose connector a little bit to make it easier. While machining the small thin tube caught on the knife and unceremoniously bent, and was damaged. While trying to straighten it, as suspected it snapped off. Dad came to the rescue and machined off what was left, then proceeded to cut a thread into the mechanism and made a new separate hose connector component that simply screwed into the end. We epoxied it in place and all was good again.

We've also had discussions about how we are going to make the top bracket that holds the boosters together. It's going to involve steam.... but more on that later. :)

Monday, May 11, 2009

Building continues

We have been continuing with the development of the booster. Here we test assembled some of the components to check for clearances and get an overall idea of how it will go together. The nice thing is that it just fits inside the house. (one inch from the ceiling)

One thing that was very evident is how high the top payload is, and we are going to have to move the flight computer down, or at least extend the Arm button down where it can be reached.

Pictured along with the rocket is a standard sized kid. Simulation says that the booster alone would lob him about 4 meters into the air. :)


Thursday, May 07, 2009

Acceleron V construction

Most of this week has been spent making the base plate for Acceleron V. Here it is partially assembled:
The sustainer air supply and retention mechanism still needs to be machined, which will be done soon.

The bottle splicing is also complete, although the bottles still need reinforcing around their necks. They also all need to be pressure tested. We made a number of spare spliced bottle pairs should any of these leak. We will give all the splices at least 1 week to fully cure.

We used PL for the splicing and Sikaflex for sealing the joints as we had leak issues when making spliced pairs for the Polaron rocket a couple of months back.