I didn’t sand the cage, just the ring, and I only did a quick half assed pass up to 220 grit. Tbh that’s plenty, for me anyways. I printed the cage at .1mm layer height, so it’s relatively smooth in the first place, and I find it’s fine as my dick doesn’t really move in the cage so the roughness/smoothness doesn’t matter much. For the ring, because your sack moves around a lot more, you notice the texture more.