I have a couple coats of finish on a cutting board I made for someone for Christmas and have a question about sanding between coats. I read somewhere to sand between coats with 400 or greater sandpaper. I have both wet or dry (silicon carbide) and 3M P400 Sandblaster Gold. Does it matter which one I use? And to add to that, the wet or dry is actually 600. So would that make a difference? Thanks in advance for any advice!