Worth it?

I doubt that it would be profitable. First, you need the hammer mill. There's $7500 that you'd have to recover to be where you started from.

Second, you need some way to run the mill. If it uses 3-phase electrcity, you'll need a hookup. If it runs off of a PTO, you'll need an old farm tractor. There's more money.

If prices were good, I could see it maybe penciling out. But, with prices where they are, it would take a lot of metal to get back to where you started from.