Latest Update:6th July 2018 - Day 199 - Phoenix 3D d78 Nosecone and UNSW Visit

Day 195 - 3D Printed Pyro Rocket & Casual flights

Date: 24th February 2018
Location: Whalan Reserve, Australia
Conditions: partly Cloudy, wind 5-10km, 34C
Members: Paul K, John K, and GK

3D Printed Rocket

Today again was  a bit of a casual flying day with the club. Earlier in the week we downloaded a 3d model of a rocket from thingiverse and printed it. All up it took around 6 hours to print. We printed the 24mm motor mount fins just in case the hole was a little smaller than the motor as it would have been difficult to make it fit otherwise. This way we just added tape to the outside of the 18mm motor to make it fit. We had also modelled it in open rocket to get the center of pressure. This way we could figure out the stability. It turns out that the rocket was marginally stable and so we added some nose weight. The whole rocket was quite heavy at around 150g with the motor and so we knew that the C6-3 motor we were intending to fly the rocket with was also going to be marginal. We had a set of SCR C6-3 motors, and so we decided to use that. We knew that it had less average thrust due to its longer burn time but believed it was still going to be ok. It was not. The rocket took off and struggled to get into the air and then kind off tumbled and hit the ground. Max altitude was around 15 feet.

No damage was done and so we set it up again. David gave us an Estes C6-3 which we know is correctly labelled and we put the rocket back on the pad. This time it took off and flew nice and straight and flew to perhaps 250 feet and recovered safely. The lesson in that is make sure you use the appropriate motor and check thrust curves carefully when dealing with marginal rockets.

Though the SCR motor is labelled a C6 it really is a C3 with about a 2 second burn time. They are nice for long burn flights but the rocket needs to be light.

Other than that Paul also flew his venerable Pod 2 and had a good recovery. One of the kids at the launch site managed to get a hold of it when it was back at the gazebo and threw it up in the air and landed behind Paul. He took a step back and broke a couple of the fins. So we have more repairs to do now. It will fly again.

We also flew our Axion G6 again a couple of times just for fun without any experiments on board. Both flights went well and had safe recoveries.

John was doing a panning shot with his drone looking down at the monitor but he looked up too late as the drone clipped the trees and crashed to the ground from about 5 meters. The only damage done was a snapped propeller, so he swapped all the props to the spare ones we carry and he was off flying again. Considering he has had the drone for a year with perhaps 25 hours of flight time and this was his first crash I think that's pretty good going.

Flight Details

 

Launch Details
1
Rocket   Techno
Motor   C6-3 (SCR)
Payload   None
Altitude / Time   ?' / ? seconds
Notes   Slow unstable launch. The rocket hit the ground first before deploying parachute. SCR motor does not have enough power.
2
Rocket   Axion G6
Pressure   200psi
Nozzle   9mm
Water   1500mL + foam
Flight Computer   STII - 5 sec
Payload   None
Altitude / Time   ? / ?s
Notes   Good straight flight with parachute deployment right at apogee. Good landing..
3
Rocket   Techno
Motor   C6-3 (Estes)
Payload   None
Altitude / Time   ?' / ? seconds
Notes   Slow launch. The rocket was stable and reached around 250 feet. Good deployment and good landing.
4
Rocket   Pod 2
Motor   C6-5 (SCR)
Payload   None
Altitude / Time   ?' / ? seconds
Notes   Good launch, and good recovery.
5
Rocket   Axion G6
Pressure   200psi
Nozzle   9mm
Water   1500mL + foam
Flight Computer   STII - 5 sec
Payload   None
Altitude / Time   ? / ?s
Notes   Good straight flight with parachute deployment right at apogee. Good landing..