In this instructable I am demonstrating the options available for painting a 3D printed model. I chose to use Testors enamel paint to test paint the batarang. In this learning experience I focus on even coats and a comparison of how 3 coats compares to a single coat. It is a bit hard to see, but I also painted the left hand layer black to see if it improved the black PLA to have paint on it.
Note: the batarang model is made as a push pin model that sticks to a bulletin board with a short side (the left side).
When the batarang is stuck to a bulletin board it would look like it was sticking into it as though thrown at the bulletin board.
Testors Enamel Paints - 10 pack of small model paints for about $12 from blick on Market and 6th in SF
Paint brush (as included in testors kit)
3D Model to paint
disclaimer: I realize that the actual batarang is all black and this painting was done for a learning experience rather than an attempt to exactly duplicate the original.
I made it at Techshop http://techshop.ws with a Type A Machines Series 1 3D Printer
Submitted by SFlettering for the Instructables Sponsorship Program
Step 1: Initial Coat - Painting in 3 Areas to Compare Multiple Coats
The first coat of red enamel testors paint was put onto the
1) right side
2) left side
3) middle area
The initial single coats of paint will be compared as I put additional coats on the right side and middle painted areas.
When painting the first layer it went down pretty well and offered about 40-60% coverage.
TIP: When painting on a 3D printed model you are likely to still be able to see the individual strands that make up the PLA print even after a single coat of enamel was used to paint over the print texture.
Step 2: Close Up - Right Side of Second Layer of Enamel Paint
In this image you can see the much improved results from letting the first layer dry for 30 minutes and then painting the second coat to cover thin areas from the first coat. The paint went on well and although I was tempted to use extra paint it ended up pooling if I put too much onto the layer.
The second paint layer provided about 80% coverage in terms of not being able to see the black color below the painted area.
TIP: A second coat is a requirement for a good quality paint job on top of PLA.
In the additional images you can see the "shorter" left side with only 1 layer of paint has less coverage and shows some of the black layer underneath.
Step 3: 2 Coats Over 60% of Surface
At this stage notice how the center circle was painted with a second layer and compare that to the red area on the left with only 1 coat.
When printing with enamel paint from Testors ( http://www.testors.com/category/135894/Enamel_Paints ) follow some basic safety precautions with fumes from both the paint and the paint thinner included in the set for cleaning your brush.
TIP: Be aware when painting and make sure to work in a ventilated area - (seriously ventilation is required).
Step 4: Painting a Smooth Surface or a Lumpy Surface
Here in this image you can see the center area that is dry with over 3 coats of thick layers and it looks lumpy and does not have a smooth appearance. The right side was done with less thick paint layers and came out with a more smooth appearance.
NOTE: There was a slight difference in the amount of paint used on the first layer compared to the second layers. This was possibly a result of paint filling the spaces in between PLA strands on the model.
TIP: When painting onto PLA printed models make sure to apply thin coats of enamel paint.
Step 5: Painting in Black on a Black PLA 3D Printed Model
When you are painting the surface of your model consider doing a color match with the PLA color for a fully consistent look of your finished model that is covered in enamel paint. Notice in the image part of the right half (near the center) was left unpainted to provide contrast with the look of the other black areas that were painted with black enamel paint.
Shine: The enamel in both the red and black areas provides a shine that is more brilliant than the unpainted section
TIP: Expect that 2-3 layers will be required to provide good coverage on top of PLA printed 3D models.