When working with plexiglass you should use two kinds, first start with sandpaper that is classified as super fine and then move to ultra fine sandpaper. This covers sandpaper from numbers 400 to 1000. Start with a lower number and then move to as high a number as you need for a smooth plexiglass surface.Click to see full answer. Also know, can you sand down acrylic?Sand the area with the wet 800-grit sandpaper until the surface is smooth and appears to be free of scratches. The acrylic can be buffed after the sanding process, but it isn’t necessary.Furthermore, can you cut plexiglass with a router? If you don’t have one of several types of power saws available to use, if you have a router, it is possible to cut plexiglass with it. Provided you have the correct blade designed to make a flush cut, a variable speed router, when done right, will cut plexiglass. Secondly, can you sand StarBoard? Sanding may be used, but a very fine sandpaper is required to avoid creating small, hard-to-clean scratches. Because King StarBoard sheet products are designed to resist water and grime, they cannot be painted and the use of adhesives is not recommended.How do you round the edges of plexiglass?To get a smooth edge, use a chop saw or a radial arm saw to cut the plexi. Then you can use a sanding block to round the edges if you want, but to get a transparent and smooth finish, use a heat gun or a stove.