Trimming the mountain off a layout to move it

I am trying to figure out the best way to cut off some mountains in a layout built of Hydrocal and foam. A recip saw may vibrate the layout too much. Perhaps a hand operated hack saw blade. Any advice? If I get real lucky, I might be able to decapitate the scenery so that it could be reassembled in place. Never done it before.
If you want to know why, the previous owner built hills that were over 2’6" high so even turning the structure sideways, it won’t fit through the doors into the basement. It’s the proverbial boat-in-a-basement.
Thanks,
Ken
The Southampton-Sag Harbour-Montauk Line
“The Route to The End”

If you can cut thru the plaster with a hand saw, can you then get between any of the layers of foam to lever it apart? I am assuming (perhaps incorrectly) that the foam was applied in layers and that you could possibly break the glue bond between some of the layers?

Use the sawzal and save the time to put it back together. The moving will cause more problems than the cutting. It will be easier than starting from scratch, but moving a layout is difficult because the tolerances are so tight. Don’t be bashful, or hesitant, just plan on a lot of adjusting to get to run again.

It is certain that the base of the mountain is plaster cloth or hydrocal to make a nice topography. Even if it is something else, I would take a small hammer and lightly ba***he base of the mountain to see how it is fixed in place. Piece away the shards of “stuff” and then see how the mountain sits. It may be glued, nailed, screwed, etc. If you can peel away the covering and see that it is fairly cleanly sitting on plywood, then use a sturdy trowel to shove between the foam and the bench and pry up. You may get lucky and find that the mountain lifts off relatively intact, in which case placing it and plastering it once you have moved will take an hour at most. Painting and scenic touch-up a bit longer.

Thanks guys. I’m going to examine it in more detail on Saturday as It has a grid benchwork so that I can look from underneath and get some more ideas. Will keep you posted. I may not need the mountains as the Long Island area (my rough prototype) is mostly flat.
Ken
The Southampton-Sag Harbour-Montauk Line
“The Route to The End”

Well, It’s hydrocal over a wire mesh base. It was recommended to me to use a Sawz-all with a fine blace and go very slow. I’ll let you know!

Disk grinder will be faster, but dusty.