I have seen pre-cut masonite circles at my cake supply store. I think it is about 1/4" thick. I was thinking to buy these, drill holes in the center, then proceed with to center bolt and separators.
Any reason this wouldn't work? I'll never get one if I have to cut my own circles!
I have been thinking about making the exact same thing. A cupcake stand with masonite boards. I'm not really sure how it would work though. I would definitely make my husband make it for me.