Reply to "Tool recommendation wanted for working with foam"

I had a local train enthusiast do some of my rock cliffs. I bought 2" pink foam. He used 3M Super 77 to glue layers together to get the right height   He just used a razersaw to scrape the foam to a basic shape then he'd cut the horizontal lines after that he'd  pick at the foam with the corner of the razersaw. It was an awful mess, but it turned out pretty good.