I have been 3D printing for about 4 years now and I have always struggled to find an easy way to smooth PLA filament. After mistakenly spraying Polyurethane on my 3D model, I decided to see if it was thick enough and would dry fast enough to fill in the layers and I'm happy to say that it does!
I put a lot of work into the video so watch it too!
You will need:
A 3D printed model with visible layer lines.
Any can of spray paint that bonds well to plastic.
Fast Drying Polyurethane - Clear Satin.
First clean the model of any dust and make sure it's clean.
Next spray the model with your selected color of spray paint.
Then quickly spray a layer of Polyurethane.
Then place it under a fan to prevent drips and to make dry faster.
The paint and Polyurethane will mix and fill the layers, any holes, and printed flaws.
The thinner each layers and the longer you let each layer dry the better.
I waited 20 minutes between layers and then waited an entire day before spraying the final coat of spray paint to cover any discoloration.
Note: I did print the skull at a layer height of 0.3 which means detail was lost during printing. A height 0.1 would have been better and taken less time to smooth but I needed an extreme layer height to show how much this method can do!
Do read and follow all safety warnings on all spray cans and 3D printers.
I hope someone out there find this helpful! Feel free to check out my YouTube channel - 3DSage for more fun videos!