My friend is really into the Red Hot Chili Peppers. I've added their logo on a plain guitar knob for him. 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.

• Size: +- 25 mm x 25 mm• Layer height: 0,10 mm• Infill: 15%• Support: yes, below the knob