The Foo Fighters is one of my all-time-favorite bands. I've added their logo on a plain guitar knob. The knob should fit easily but thight enough to twist the button. If it's too loose you can add some superglue or wrap some tape around the tiny stick on your guitar to make it a bit wider.

I printed it on 0,10mm layer height to make sure every color on top had atleast 2 layers.