Here are photos of several coating blades.
From left to right, 16", 12", 11" and 8". This is the width of usable coated area. The length is based on how well you can pull the blade at a constant rate. My max is about 22 - 24" for the 16" blade.
I've appended a photo of an 8" coating in progress showing the draw. This is a frame that I clipped from the DVD, so you will see raster lines. Sorry. The point of this photo is to show the draw and show the waste at the top. There is also selvege along both sides due to surface tension, and there is a defect at the end when you reach the limit of the coating plate.