FDM 3D printing is quite streaky, and looks... well, like it was 3D printed. I print in PLA, so acetate vapor is out off the question, making good, old fashioned sanding and painting the easiest way to get it looking it good.

The first time I tried this I sanded the thing completely smooth, and it took ages. I found other people have had success using automotive primer/filler which fills smaller scratches.

I tried this, but the gaps were too big. I went aggressive, and started with 120grit wet-and-dry sand paper. I added another two coats of primer/filler. Next, I went to town with 400 grit, then 800 grit.

I wanted to see if I could paint a logo in the top, so I did an undercoat of satin silver, placed a sticker over it and then painted a top coat of satin grey.

It looked terrible.

1. The sticker lifted, so the edges off the logo were blurry.
2. Satin shows up ALL the gaps, so even after all the sanding, the lines were still visible
3. I over painted, so there was drips, and it looked thick and gross
4. The colour wasn't... great.

I re-sanded with 400-grit to get rid of the paint, and polished again with 800-grit. This time I omitted the extra coat of primer/filler, and just applied two LIGHT coats of flat (matt) black paint. This time the result was great!

Matt paint actually fills gaps a little bit, so the result is much better. There are still some visible lines (in the right light), so clearly I need to sand more. Also - I missed some bits on the bottom section. Clearly I still need some practice.

I wouldn't mind trying the satin finish again, with out being so heavy handed on the paint.