This is part 7 of our tutorial series on how to build Arrma Limitless from the ground up. In our part 6 tutorial, we learned how to install a brushless motor. Now, let’s look at how to spray paint the body shell of Limitless.
Arrma Limitless V2 comes with a transparent polycarbonate body cover. This Lexan shell is coated with a thin film of plastic on the outside which we will remove in the final step.
List of Tutorials
Below is the list of all the tutorials in this series.
- Getting Started
- Installing Servo Motor
- Installing ESC
- Installing Receiver
- Installing Servo Horn
- Installing Motor
- Spray Painting the Body
- Applying Decals
Things You Need
Here are the things you need to proceed.
- Limitless polycarbonate body cover – comes with Limitless
- 100ml polycarbonate spray paint – most common ones are from Tamiya
- Limitless masking stickers – comes with Limitless package
- Dishwashing liquid and sponge
- Dry cloth or hair dryer (optional)
- Gloves (optional)
Choosing the Right Spray Paint
You should only use polycarbonate spray paints such as the ones from Tamiya. This type of spray paint allows the paint to adhere permanently and will flex with the body. Other types of spray may chip or crack. A single 100ml spray can is usually sufficient to get the job done but for some colors, such as the translucent yellow (PS-42), it takes more than a can to complete the entire shell. In this tutorial, we shall use Tamiya’s metallic purple (PS-18) spray paint.
Darker colors tend to require less spray paint than lighter colors. From our experience, we only need one can for using metallic purple, while we needed 3 cans for translucent yellow.
Cleaning the Body
Firstly, we need to remove any residue on the body. Wash the inside of the body shell with dish soap and a soft sponge. You do not need to wash the outside of the shell because we will not spray the outer layer.
Then, wipe dry using a soft cloth or air it to dry naturally or using a hair dryer. If you choose to wipe dry the body shell, try not to use a material that will leave some dust or fiber behind such as tissue paper.
Applying Masking Stickers
Once the body is completely dry, you may begin to apply the masking stickers (REV_0 ARB100026513) provided by Arrma. It is meant to protect the windows from being sprayed with color. There are three pieces of stickers and you should apply them on the inside. The result should look like below.
Ensure you properly sealed the edges of the windows with the stickers. Otherwise, paint will leak through and smear your windows.
Spraying the Body Shell
Find someplace that is well-ventilated but not windy. Use proper sheets to cover the areas from spray paint. Then, shake the spray can to ensure the paint inside is properly mixed.
Next, begin spraying the inside of the shell by applying multiple layers and using a sweeping motion from left to right or up and down. Do not spray straight at one area because this will cause the paint to build up and cause dripping.
Depending on your weather, let each layer dry for about 10 minutes before you spray the next layer. We sprayed five to six layers to complete the job. You should concentrate on the narrow areas on the shell where paint could not easily penetrate, particularly on the front wing.
Go around the shell when spraying to check out areas with uneven paint. You may also hold the shell against a light or the sun as this helps to reveal areas that have thinner paint than the other.
The nozzle of the Tamiya spray paint is narrow thus preventing the paint from spreading to a wide area. You may choose to hold the body while spraying. This helps to find missed spots.
You may not want to finish the entire can of spray so that you can do touch-ups later to cover up future scratches. Once done, you should get something like below.
Sometimes the masking sticker may wrinkle and cause smearing on the windows, as shown below. You may clean the window later using light acetone solution (nail polish remover) with a sponge but it may leave some haziness.
Do not use strong 100% acetone as it will eat into the lexan shell and create a vivid cloudy mark.
The next step is to remove the thin plastic layer on the outer side. You may choose to keep the layer on to protect the shell. This is up to your choice.
Final Result
In the end, you should get a nice shiny Limitless body shell in your favorite color. The photo below shows the difference between leaving the thin plastic layer on and off.
Please don’t expect a perfect paint job. Most of us are not professional spray painters, so it’s fine to make some mistakes when we perform this task. The good thing is that it’s hard to notice the tiny errors when viewed as a whole.
If you’re an owner of Arrma Limitless, join us to get a chance to be a world champion in Formula RC.
