Hopefully not a stupid question, is there an abrasive pad that will take down filler and not touch the carbon? Some aero surfaces are just a couple of plys over foam and need filling and it takes an age blending without rubbing through any material.
Not a stupid questions, but a hard one to answer. There isn’t a specific abrasive pad that won’t take down carbon, but there are methods for minimizing the ware on the carbon as you take down filler material.
- Tape off the carbon that you don’t want to get sanded.
- Use the highest grit possible to achieve the surface finish desired.
- Use good filling techniques to minimize the amount of additional sanding required.