The finish of the Epoxy on the CF air-frame wasn’t staying shiny/beautiful. Also there were a few imperfections that I wasn’t happy with. So I decided the best course of action was to apply a clear coat. I could then sand to 2000 Grit and polish it to perfection.
The Paint
I used Acrylic clear coat from AutoBarn – a large can.
ClearCoat paint used.
The Test Run
I first did a test run on a piece of tube because I didn’t want to assume it would just work.
To my shock after a few coats of clear coat it looked terrible and I thought that I would have to forget applying a clearcoat until I found out what was a happening. I thought it was perhaps due to humidity, but I was advised by a friend that you might have problems with rain, but humidity should not cause what I was seeing.
So I decided to sand it from 1500, then 2000 and finally 3000 before polishing.
The test tube comes up looking really good after sanding 1500,2000,3000 and then polishing!
Thank heavens!
The Real Run
I then proceed to apply clear coat to the rocket. I applied 4 coats. Below are some photos I took.
First coat of clear done.Rocket after several coats – starting to lose the gloss look…for now.
Here is photo of it looking splendid at a presentation of my rockets.
Rocket after sanding and polishing. Looking Splendid.
In the first paint session I managed to paint the nose coat with base coat and clear coat. I base coated the booster, but had some issues and ran out of blue base paint.
The second paint job is to complete the painting tasks. For the second paint session I decided to purchase a gravity-fed spray gun.
$30 dollar spray gun – Gravity fed. Well worth the investment.
For the second paint session I purchased new :-
1 litre of blue paint
0.5 litres of thinner
0.5 litres of hardener (activator)
Second batch of paint products for painting booster using new Gravity Fed spray gun.
Unfortunately I didn’t take too many pictures during the second paint session. I was too busy concentrating on the job. The base coat (blue) went fairly well. I have a photo of the booster hung up below.
Photo during painting. Using the gravity fed spray gun.
The big differences this time was :-
The use of gravity fed spray gun with regulator. This meant I could actually get the air coming out at the right pressure. With the previous gun, I had no really control over the pressure (well I had no knowledge of what it was set to).
More base coat to experiment with
Lowered the whole rocket about 15cm to make it easier to paint. Arm won’t get as sore.
Had special tray for cleaning gun between base and clear coat
Purchased 4 litres of thinner specifically for cleaning the gun. So now I don’t have to use the precious thinner that is supposed to be used for the paints.
Rather than waste valuable thinners used in painting, decided to purchase some, just for cleaning.
Problems experienced during painting
Unfortunately I did get a few runs with the clear coat and I’m very sure it is because I went over the fin-cam too many times. i.e. three passes, when two passes would have been sufficient. The spray was open wide and there was more overlap than I expected. This is due to my inexperience.
I decided not to sand back down to base and do it all again. I decided to just remove the obvious runs and polish the rocket.
Removing the Runs
I removed the large runs by applying some polyster filler compound. After 20 mins it was set and I sanded it down using grit 400 sand paper. This meant I was only sanding the runs and not the area around them. It worked very well. Then I sanded it down with 1200, 1500 and then 2000 to removal all remaining traces of the runs. There is still some undulation of the clear coat because of the flow of the clearcoat, but it is only slightly undulating and is very smooth.
Reflecting on the results
So while I didn’t get the best result, I did learn a lot on what went wrong and how to remedy some of the issues I created. I have to remind myself this is my second paint job in my life. It went reasonably well considering!
Painting is to commence on the Sunday (3rd Dec 17), but decided to spend a few hours on the Saturday making sure everything was ready and I’m familiar with the operation of the tools.
Making sure the Compressor works satisfactorily
Looking at the operation of the Spray Gun
Making sure the rocket is level and at appropriate height
That we will be able to paint the Nose Cone while the rocket remains hanging
It was a good thing we checked because I noticed that:-
The rocket was not at the right level, it was too high and this would result in tired arm.
The Nose Cone jig was right on top of the rocket, and this would mean I couldn’t hang it up and paint it at the same time. So I moved it to the right
All these might seem like small points, but they all go to help make it a successful paint job.
Here are some more pictures of the area where I will be painting the rocket.
Tape on inside to reduce amount of paint getting on inside of air-frame.Backing masking tape so that paint doesn’t go onto inside of air-frame.Toothpick to reduce amount of paint going into threads.Rocket suspended from garage door at just the right height. Nose cone is also suspected from eye-bolt to the right.Just double checking that the level of the rocket seems to be at a comfortable height.
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, 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!HoseSpray 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.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.
