Question: is mdf the same as masonite?
Answer: Tempered Masonite is very hard and almost glossy on one side. Untempered Masonite is more porous on the flat side, not as glossy, but still pretty hard. MDF, while made a similar way, isn't as dense throughout as Masonite, and generally has a separate "skin" laminated to it all around. It comes in boards and sheets.