Category Archives: Purchasing

L2 Certification, Painting, Planning, Purchasing

Selection and Purchase of Paints and Equipment

One of the next tasks is to paint the rocket. I’ve decided to use Two-Paks. I purchased some painting supplies from ColorTek in Cairns.

Two-pak paints - includes gas-can sprayer, thinner, primary and hardner.

Two-pak paints – includes gas-can sprayer, Thinner, Primer and hardener.

I’m not sure what colours I want to paint the rocket, so I’ve had to delay the purchase of these.

Painting hardware

I was thinking that I would need to purchase a spray gun and compressor; however my wonderful neighbour has offered to loan me his. Initially thinking that I should use his for priming and purchase my own gun for the base coat and clear, but now thinking we might be able to use his Spray-gun for all coats. His spray-gun is 1.5 mm orifice which means it is sits between the 1.3 mm good for base paints and 1.7 mm which is good for Primers. So his spray gun should be suitable for all coats (primer, base coat and clear).

Massive air compressor!
Massive air compressor!
Hose
Hose
Spray Gun - 1.5mm orifice
Spray Gun – 1.5mm orifice

 

 

Having a practice run at painting

I decided to try doing a practice paint run using the Colorpak gas-can sprayer. Below are some photos of the results.

 

Inspecting paint job - 3 layers of primer on PVC tube.
Inspecting paint job – 3 layers of primer on PVC tube.
Close up view of painted surface before painting.
Close up view of painted surface before painting.

I will more then likely do a small test run on the day before I start painting the rocket – though I’m not expecting too many issues.

L2 Certification, Purchasing

Purchase of Parts

I’ve made another purchase of parts for my build. I have ordered:-

  • Raven 3 (70G)
  • 84 inch rip-stop nylon conical parachute, ~16 inch spill hole
  • LOC ANGEL Drogue Parachute
  • Tubular Nylon 0.5625 inch (per metre)
  • NOMEX 12×12 for up to 4 inch Tube
  • Remove Before Flight tag (Pink)

I discuss my choice of component below.

Raven 3 (70G)

Manual is downloadable from:-

http://www.featherweightaltimeters.com/uploads/Raven_Users_Manual_13April24b.pdf

This is a very well spec’d altimeter. It beeps a lot when you turn it on to alert you that things are operational and satisfactory (though many probably do)

It is a very light, small sensor. This will leave plenty of room for other components, etc inside the rocket. Unfortunately it doesn’t have a gyroscope, but there is nothing stopping me installing my own gyroscope sensor/electronics.

However it is a popular, well proven piece of hardware.

84″ Main Parachute

This has been sized to lower the rocket at approx 6ms-1. This is an upper limit. I suspect it will lower the impact speed will be a little lower. This parachute has also been chosen because it is of stronger construction, which I think will be necessary because the rocket will be travelling ~22ms-1 when it is deployed. This is fairly high speed deployment.

NOTE: Blake from AusRocketry has suggested that using a LOC ANGEL parachute (large?) would do the job well and might be easier to pack into the parachute bay. Using the calculations on the webpage with known weight of the rocket, we would be looking at a decent speed of about 5 ms-1.

LOC ANGEL Drogue Parachute

I really wanted to get a 28″ or 30″ Drogue, but they seem hard to come by. This is a 24″ drogue and checks have shown that it SHOULD reduce the speed of the rocket to about 22ms-1. If I see/learn of reasons for a major deviation upwards, will need to consider purchasing an alternative Drogue Chute.

NOMEX 12×12 for up to 4 inch Tube

This is wrapped around the Parachute to protect it from the exhaust gases. I expect that this will be attached to the shock-cord, so we don’t lose it at ejection.

I got two of these, one for the Drogue, the other for the Main parachute.

Remove Before Flight tag (Pink)

I’m going to have ONE switch to turn everything on/off.  I didn’t really want Pink coloured one, but there weren’t many others.

Later I convinced myself that Pink is just fine, infact it is highly visible and should be no missing it!