How flat is flat for self levelilng compound; special application
This may sound like a strange application. I am making a small jig that needs to be as flat as possible, for my woodworking and printmaking hobby. I was originally thinking about getting a granite remnant from our local stone shop but they don't want to give anything away, it's all 25 bucks a square foot for small pieces and I need about 3.5 square feet.
So instead of granite I was thinking about building a wood frame and just pour some self leveling compound in it and use that as my flat surface. Much cheaper.
What I was wondering, how flat can I expect the surface to get?