Not that I'm an expert at all but it looks rather difficult to me. I would rather kick the 100.00 bucks or so for a premade, that is if my bees ever make enough honey that i would need one.
I'm with you although they are a heck of a lot more than 100 bucks. That two frame plastic job, from what I have heard, is a piece of junk. You may get lucky and find a used stainless steel extractor for $100 but I wouldn't hold my breath. I have a 3 frame, which is great for a beek with a few hives. I'll probably be selling mine in the next year or two. I am quickly outgrowing it.